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Raised and bent bars

C

cbr1000dude

Bicycle
I'm not sure if this is tech or accessories, so feel free to move it as you see fit.
I changed my 1 inch spacers for 1 1/2 sockets and got longer bolts.

This was close, but I didn't like the angle of the grips, so I bent the bars forward about 1/2 inch at the bar weight ends.

Now it feels just right to me. The bars bent at the point between the lever perch and riser, I'm not sure if you can see it in the photo. I put the front wheel against the wall, turned the bars to lock, and pushed it where I wanted it. They bent quite easily without a long bar I've used to bend other things. Both sides match to my eye and feel. I lowered the shift lever just a bit too. I think I've got it for now.
If this offends anyone, just look away please.
 
Very ingenious!  :great:

You have also proven why the C14 should not be anchored to a trailer with straps attached to the grip ends, like Canyon Dancers.

If you could bend the bar that easily, imagine what a pothole in the road could do to them if tied down from the grips.
 
Yes, the bars themselves are about as hard to bend as boat bimini top frame tubes, look kinda like them too. Good point!
 
Aluminum work hardens very easily (depending on alloy and annealing). I would suspect that the bars are a "hard" alloy such as 7075. This is a zinc alloy and does not take to cold forming well. I would be very careful with stress riser cracking! I'd recommend keeping a close eye on the bend point for signs of metal fatigue!
 
"If this offends anyone, just look away please."


Since you posted this in a public forum you understand that you might get some comments you don't like. With that in mind, it never ceases to amaze me what can be accomplished a little ingenuity and even less concern for the possible unintended consequences of decisions.
 
Nothing ventured, nothing gained is my motto.
I'm fully aware that all of my tinkering can have unintended consequences, and it has, at times in my life. However after many years of trial and error, my projects usually turn out just fine. I only learn by trying something new.
I do fully expect "helpful warning" comments, it happens on some forums more than others. I do wonder how someone can know the handlebars are 7075 aluminum alloy or what temper they have just by looking. Seems to bend pretty easy for such a hard alloy!
The amount of bend is such a small percentage, I'm not worried about it. I've bent aluminum before. Have you? How did it turn out?
I'm just posting my solution and hopefully some interesting photos for your viewing. ;D
Last summer I restored this 1990 Ski Nautique. I made the bimini top and frame from an extra one I had from a much larger boat. I bent and cut the aluminum to size with homemade wooden blocks. It has held up fine to repeated stress. Some of the bends and unbends were about 70 degrees. So when I say the handlebar bends about as easy as a bimini top frame, it's from personal experience.
 
LakeTrax said:
Very good, but the main question here is..........
Are the 1 1/2" "socket risers" Snap-On? :D
Click to expand...
Craftsman actually! This has the added advantage of having a 14 mm thru 19 mm deep socket with me at all times. ;D
 
Dude (Never thought i'd use that term) very ingenious solution. I've made a few sets of longer bars and I used solid 6061. I thought the stanchions would break before the bars would bend. The boat top is made with tubular alum. and should bend fairly easily, but I'm shocked those bars would bend with just human strength. I don't think the bars are made of 7075.
 
Hey Dude, this is a family friendly forum. You are going to have to be more careful about the photos you post. I fixed up the one you already posted but please be more sensititve to our younger viewers in the future (Kirby is only five years old).



Brian

dude said:
Nothing ventured, nothing gained is my motto.

<snip text and that disgusting photo>
Click to expand...
 
philipintexas said:
Dude (Never thought i'd use that term) very ingenious solution. I've made a few sets of longer bars and I used solid 6061. I thought the stanchions would break before the bars would bend. The boat top is made with tubular alum. and should bend fairly easily, but I'm shocked those bars would bend with just human strength. I don't think the bars are made of 7075.
Click to expand...
Philip,, I never thought I'd say this to a guy, but, nice rack! Maybe Santa will bring me one.
 
BDF said:
Hey Dude, this is a family friendly forum. You are going to have to be more careful about the photos you post. I fixed up the one you already posted but please be more sensititve to our younger viewers in the future (Kirby is only five years old).



Brian

dude said:
Nothing ventured, nothing gained is my motto.

<snip text and that disgusting photo>
Click to expand...
Click to expand...
Sorry about the wardrobe malfunction! :-\
You cracked me up, Brian.
Notice I used a comma so it didn't say up Brian.
 
Yeah, it pays to be careful.

Glad the gist of it made it across the 'Net- sometimes I make a funny and it just does not go over quite right.

Brian

dude said:
Sorry about the wardrobe malfunction! :-\
You cracked me up, Brian.
Notice I used a comma so it didn't say up Brian.
Click to expand...
 
Kind of clever but do keep an eye on the bars! Since we don't know the material, we're not sure how brittle or ductile the bar material is. Structural materials do fatigue also and what I've learned through years of working in the structural realm (mechanical engineer) is that when you strain a material to a high stress (yield stress (permanently bent) is high! :-\) very small cracks or defects can be initiated that will propagate at much lower stress levels, like pushing on the bars when braking hard. I'm not offended but I'd recommend giving the bars a good look-see about once a week, preferably with a magnifying glass.

Stay safe
Pete
 
Yeah, it's a good idea to check out all the nuts and bolts for tightness before each ride too. I found 2 more loose ones after my ride yesterday
You especially should check for the loose nut behind the wheel! :-\ Oh wait, that's me. Never mind.
 
BDF said:
Hey Dude, this is a family friendly forum. You are going to have to be more careful about the photos you post. I fixed up the one you already posted but please be more sensititve to our younger viewers in the future (Kirby is only five years old).
Brian

dude said:
Nothing ventured, nothing gained is my motto.

<snip text and that disgusting photo>
Click to expand...
Click to expand...

:rotflmao:

Good one!
 
philipintexas said:
Dude (Never thought i'd use that term) very ingenious solution. I've made a few sets of longer bars and I used solid 6061. I thought the stanchions would break before the bars would bend. The boat top is made with tubular alum. and should bend fairly easily, but I'm shocked those bars would bend with just human strength. I don't think the bars are made of 7075.
Click to expand...

I didn't know your long bars were 6061 but they are heavy enough so I was wondering. I really like them, btw.
 
Yeah, we're not sure what they're  made of but taking a look at them this morning, they look like a casting, which wouldn't be as ductile as the extruded aluminum tube of the boat top. Keep an eye on them.
 

The bar that I bent is #46003. It's a straight aluminum bar with some holes tapped in the ends, and retaining holes for the perch. Not the cast riser part. The best way I know how to see if something will bend, is to bend it! ;D
When I was a kid, I rode a 350 Honda scrambler to the Hayward hill climbs, climbed hills, and rode it home and straightened everything I bent. Later in life I rode a 450 Husky at Carnagie before it was a State motorcycle park. I bent it a lot too.
Some bent back to shape, some broke and I got a new or used one from the Honda dealer. So I guess my perspective is different. Bending stuff is what I do. Drilling holes in it and grinding and polishing it is even more fun for me.
 
JR: The ones on my bike appeared to be 6061, sometimes I can tell by how hard the metal is with a file or a machining process, but it's an educated guess. I can make them of either material.
 
Yeah, those bars are mill finish, used in the as- rolled condition and almost certainly 6061- T6. That material is quite tough for aluminum and any micro cracks do not tend to propagate and gather (like they would in cast iron for example). Personally I would not worry about it because 1) they are about 17 times stronger than they need to be and your having bent them probably only reduces that to 14 times too strong and 2) in the initial phase of deformation, materials actually get stronger. Not sure you got to that phase of course but still, as long as you did not put a 30 degree kink in them I think they will be fine.

What I am a bit suprised about if the fact that the actual handlebars bent rather than snapping off the stanchions! In a really left- handed way, this indicated to me that the stanchions are really much, much stronger than I had originally thought. And the other really good news is that if the round bars bend before the stanchions crack, the whole assembly (or more correctly, the weak link- the actual handlebars) will bend before breaking if enough stress is applied and become obvious to the user that something is wrong long before something actually breaks. It is enough that I would no longer worry about using Canyon Dancers on this bike (going to get a lot of crowd heckling for that one I bet).

It also indicates to me that the very few broken stanchions we have heard about must have been defective right from the factory rather than just being an inherently weak design. Of course I always did think that Kawasaki was collective smart enough not to actually sell a motorcycle with structurally deficient handlebars....  ::)

Good post and good info.- thanks for sharing (everything but that disgusting photo!).

Brian

dude said:

The bar that I bent is #46003. It's a straight aluminum bar with some holes tapped in the ends, and retaining holes for the perch. Not the cast riser part. The best way I know how to see if something will bend, is to bend it! ;D
When I was a kid, I rode a 350 Honda scrambler to the Hayward hill climbs, climbed hills, and rode it home and straightened everything I bent. Later in life I rode a 450 Husky at Carnagie before it was a State motorcycle park. I bent it a lot too.
Some bent back to shape, some broke and I got a new or used one from the Honda dealer. So I guess my perspective is different. Bending stuff is what I do. Drilling holes in it and grinding and polishing it is even more fun for me.
Click to expand...
 
My spec. sheet on 6061 alum. shows a "yield" strength of 40,000 Lbs. per square inch. (Similar figure for tensile strength) The bars are .875 diameter which gives an area of .6". That's 24,000 Lbs. of yield strength. Maybe I don't understand the definition of "yield strength", but does that mean "Dude" applied that much force to bend his bars, AND the stanchions didn't break??
 
Well, yield is not the point where something begins to bend, it is the point where it has failed outright. And yield along with tensile strength are always measured in tension, not bending. So if you were to mount (easy boys!) a piece of 7/8" diameter 6061 in a tensile tester, such as an Instron machine, yes, it would take 24,000 pounds of tensile (pulling) force to cause the material to actually fail.

A cantilevered bending test, which is what we are talking about here, is a very different thing with very different parameters.

To give you a simple example, suppose you had a piece of steel rod, say 1/8" in diameter and 12" long. You could easily bend it in your hands but there in no way you could pull it apart into two pieces of material. That would be the difference between a bending test and a yield test.

Brian

philipintexas said:
My spec. sheet on 6061 alum. shows a "yield" strength of 40,000 Lbs. per square inch. (Similar figure for tensile strength) The bars are .875 diameter which gives an area of .6". That's 24,000 Lbs. of yield strength. Maybe I don't understand the definition of "yield strength", but does that mean "Dude" applied that much force to bend his bars, AND the stanchions didn't break??
Click to expand...
 
"1) they are about 17 times stronger than they need to be and your having bent them probably only reduces that to 14 times too strong and 2) in the initial phase of deformation, materials actually get stronger. Not sure you got to that phase of course"

Brian, how do we know this, did you do a structural analysis of these bars? You are right in that we don't know how they have been changed by bending, maybe some cold hardening. Yes the cold rolled tubes that the grips reside on probably don't initiate cracks that easily, my concern is the cast vertical members, I guess what you're calling the stanchions. You don't know that they are not cracked unless a thorough inspection is done on them. They might have even deformed a little bit but not enough to detect without measuring them.




"And the other really good news is that if the round bars bend before the stanchions crack, the whole assembly (or more correctly, the weak link- the actual handlebars) will bend before breaking if enough stress is applied and become obvious to the user that something is wrong long before something actually breaks"

This is speculation. A lot will depend on how the load is applied. I don't see how it will be obvious to the rider to know if the cast stanchions are cracked or not. Cracks are often not easy to see, especially at stress concentrations. Examining my bars shows they still have casting flash that was not completely polished off, so there are stress concentrations there. Some unknown torsion loads were applied to the stanchions when he bent the upper bars and there's no way to know the max stress that was seen on the part and if a crack was initiated on it.


Well, yield is not the point where something begins to bend, it is the point where it has failed outright

This statement is absolutely false. Yield strength of a structural material is the stress level where the material has 2% plastic (i.e. it won't return to original shape) strain, where the stress strain curve bends over some and becomes non-linear. It is not the point at which separation occurs. It will continue to carry additional load up to ultimate tensile strength (UTS) at which point it breaks. UTS is the point at which it breaks.

So, not trying to be a smart aleck, but since it is so safety critical to not have bars break off while riding (that's a bad thing!), we should not speculate at all. A micro-crack could have been initiated in the stanchions when the bars were leaned on. None of us know either way.

Like I said Dude, keep an eye on the stanchions. They may be fine but nobody on here knows. If you don't see any cracks, then it's very unlikely that they will come right off in the near future. But check them periodically and if you see any signs of cracks, well then just buy another set on EBay and be safe.

take care,
Pete
 
Mid_TN_rider said:
"1) they are about 17 times stronger than they need to be and your having bent them probably only reduces that to 14 times too strong and 2) in the initial phase of deformation, materials actually get stronger. Not sure you got to that phase of course"

Brian, how do we know this, did you do a structural analysis of these bars? You are right in that we don't know how they have been changed by bending, maybe some cold hardening. Yes the cold rolled tubes that the grips reside on probably don't initiate cracks that easily, my concern is the cast vertical members, I guess what you're calling the stanchions. You don't know that they are not cracked unless a thorough inspection is done on them. They might have even deformed a little bit but not enough to detect without measuring them.

No, I was being somewhat facetious. As you cannot bend the bars with your hands, and that is what is meant to be attached to them, then by default they are more than strong enough.

The stanchions, or what you are calling vertical members, are die cast aluminum and unlikely to develop a small crack under an extreme load but rather snap clean into two pieces.

Finally, the handlebars you are calling tubes are not tubes at all but mill finished (raw is another word) of solid aluminum.



"And the other really good news is that if the round bars bend before the stanchions crack, the whole assembly (or more correctly, the weak link- the actual handlebars) will bend before breaking if enough stress is applied and become obvious to the user that something is wrong long before something actually breaks"

This is speculation. A lot will depend on how the load is applied. I don't see how it will be obvious to the rider to know if the cast stanchions are cracked or not. Cracks are often not easy to see, especially at stress concentrations. Examining my bars shows they still have casting flash that was not completely polished off, so there are stress concentrations there. Some unknown torsion loads were applied to the stanchions when he bent the upper bars and there's no way to know the max stress that was seen on the part and if a crack was initiated on it.

Depends on your point of view perhaps but if one stresses a system sufficiently to deform some part of it, and that part is clearly deformed, then I would say that common sense says that the weak link is the part that bent. As to your theory of the stanchions <may> be slightly cracked and just waiting to fully fail, see the above paragraph; I think that highly unlikely. But if you want to speculate, how about the front axle? Or the front wheel? Or the front of the frame where the steering tube mounts- perhaps all of those areas have been stressed, slightly cracked and on the brink of failure. It could be the case but I would ride that gentleman's bike without worrying about any of those things- speeding tickets and deer strikes would occupy my mind rather than potential micro- cracks standing by to sneak up on me and get bigger.

Well, yield is not the point where something begins to bend, it is the point where it has failed outright

This statement is absolutely false. Yield strength of a structural material is the stress level where the material has 2% plastic (i.e. it won't return to original shape) strain, where the stress strain curve bends over some and becomes non-linear. It is not the point at which separation occurs. It will continue to carry additional load up to ultimate tensile strength (UTS) at which point it breaks. UTS is the point at which it breaks.

OK, but look at the curves. Yield is close enough to ultimate strength of tempered materials as to be considered the same. Of course this assumes that the bars are indeed 6061- T6 but I do believe that to be the case.

So, not trying to be a smart aleck, but since it is so safety critical to not have bars break off while riding (that's a bad thing!), we should not speculate at all. A micro-crack could have been initiated in the stanchions when the bars were leaned on. None of us know either way.

Then as all die cast C-14 stanchions may have been subjected to enough stress to cause a micro- crack at some point in its past, are you saying these bikes should not be ridden at all? Or thoroughly tested for micro- cracks. If that is the case, please tell me of a viable method to test for such cracks crossing the long section of the stanchions; radiography won't work, and ultrasonic testing will only detect longitudinal cracks. What method would you suggest then?

Like I said Dude, keep an eye on the stanchions. They may be fine but nobody on here knows. If you don't see any cracks, then it's very unlikely that they will come right off in the near future. But check them periodically and if you see any signs of cracks, well then just buy another set on EBay and be safe.

Are you saying micro- cracks will be visible to the mark I eyeball? Really?

I will stand by my original statement; if the gentleman put enough force on the handlebars to bend 7/8" solid, tempered aluminum and the stanchions did not snap off while he was doing that, odds are greatly in his favor that there is nothing wrong with the stanchions now. And 'looking' will not show micro- cracks in any event.

take care,
Pete
Click to expand...

Brian
 
The stanchions, or what you are calling vertical members, are die cast aluminum and unlikely to develop a small crack under an extreme load but rather snap clean into two pieces.

Brian, this is wrong. A high stress event can cause micro-cracks (one which Kawasaki didn't intend, not just normal riding of the motorcycle). We don't know if what he did was really high stress on the stanchions, right we really don't know, but they could have been and could cause micro-cracks. No they won't be visible to the naked eye and could even be internal and no it won't necessarily break clean off, only if it exceeded ultimate tensile strength. But there is such thing as fatigue, which is a phenomenon where the small defects, inclusions, and micro-cracks grow under repeated cycles, even low stress amplitude cycles, especially in aluminum since there is no endurance limit (Se) for non-ferrous materials. You seem to be unfamiliar with fatigue. Most failures of structural components fail under fatigue, repeated loadings that cause cracks to grow. Hopefully if he inspects them periodically he can detect a crack before it grows enough to overload the remaining material.


As to your theory of the stanchions <may> be slightly cracked and just waiting to fully fail, see the above paragraph; I think that highly unlikely. But if you want to speculate, how about the front axle? Or the front wheel? Or the front of the frame where the steering tube mounts- perhaps all of those areas have been stressed, slightly cracked and on the brink of failure

The slight cracks or micro-cracks are from the unintended event of pushing on the bars hard enough to bend the upper bars. Obvious other parts of the bike have not been subjected to unusual loads.


It could be the case but I would ride that gentleman's bike without worrying about any of those things- speeding tickets and deer strikes would occupy my mind rather than potential micro- cracks standing by to sneak up on me and get bigger.

Yes obviously he shouldn't inspect for cracks while riding. But the fact that you're mocking me about micro-cracks is an indication of your ignorance of structures.


OK, but look at the curves. Yield is close enough to ultimate strength of tempered materials as to be considered the same

There not the same, that's why yield and ultimate are defined distinctly and to dismiss them is also an indication that structures is a subject you don't have a great deal of experience in.


Then as all die cast C-14 stanchions may have been subjected to enough stress to cause a micro- crack at some point in its past

Why would we conclude this? I'm saying potentially only the ones where the owner decided to bend the bars.  I don't know for sure but what I do know about structures urges me to recommend for his safety sake that it's worth his time to keep an eye out for cracks, cracks that would grow  under repeated loading cycles like leaning on the bars when braking.


I will stand by my original statement; if the gentleman put enough force on the handlebars to bend 7/8" solid, tempered aluminum and the stanchions did not snap off while he was doing that, odds are greatly in his favor that there is nothing wrong with the stanchions now. And 'looking' will not show micro- cracks in any event.

You can stand by this statement but there's no basis for it. The fact that they didn't snap off does not mean micro cracks weren't initiated and if so they will grow over repeated cycles; Do some reading on fatigue. I don't know if any cracks were initiated and based what you wrote I'm pretty certain you don't know either.

Brian you post a lot and seem like a pretty smart guy, but there's no reason to assume there aren't people on here that have greater knowledge and experience in some technical areas than you do. There's quite a few technically smart people on here. My expertise is structures with multiple advanced engineering degrees and 30 yrs experience in mechanical design and structural analysis. Things you wrote indicate you do not have the level of expertise in structures that I do. In fact you missed a mistake in my last post that I'm sure you would have been glad to point out if you caught it (yield is defined at 0.2% strain not 2% like I wrote) but it was late and my son kept interrupting.

And I mainly commented on this thread because knowing what I know from much experience, I felt like I ought to help a fellow COG'r stay safe.

Take care
Pete
 
Wow, I had no idea of the level of knowledge you guys have! It's amazing I've survived this long considering the amount of modding I've done with no formal education. I just thank my lucky stars you guys are looking out for me. Too bad for me you both reached opposite conclusions!
Perhaps I'll alternate days when I worry about it or be reassured just be be safe.
What's funny, is that I was testing my homemade risers to see if they loosened up or broke under stress when I noticed that the bar was bending. So I tried the other side, and it bent too, so I bent it to match the other side. The risers held up fine, and only one bolt was slightly looser after all this. I liked the new angle, so I took the Peewee Herman approach of "I did that on purpose". (Quote from Peewee's big adventure movie for those that missed this classic).
Guys, with the Bay Bridge broken bolts fiasco fresh in the news, I'm skeptical that anyone can really tell what the future holds. I rely on how it feels to me, and it feels fine. I'm not suggesting anyone else try this. I see kids doing wheelies down the freeway in T shirts, so everyone does what they feel is an acceptable level of risk, we all just come to our own conclusions.
 
gPink said:
Dude, all that technical jargon is great but I can't get past using sockets for risers.  :)
Click to expand...
Me neither... That's why I asked if they were Snap-On! :rotflmao: I would worry more about micro-cracks developing in the stanchions from over-torquing the stanchion mounting bolts with sockets underneath than from hand-bending the bars while they're mounted to the bike. I'm guessing that if 6-point sockets are used with the 3/8" drive side facing up then you're ok- :)) Seriously though, this is an interesting set-up that I never thought of-

What I learned here is that it may be acceptable to bend the bars on my C14 to my liking if they are first removed from the stanchions? That would at least eliminate the possibility of cracking a stanchion-

dude said:
I liked the new angle, so I took the Peewee Herman approach of "I did that on purpose". (Quote from Peewee's big adventure movie for those that missed this classic).
Click to expand...
Dude, that's hilarious! This is my other favorite scene from that movie-
Pee-wee's Big Adventure - Bike Crash
 
Dude, even though I wouldn't bend my bars the way you did, sounds like your being wise and keeping an eye on them. I agree with LakeTrax that removing the bars from the Stanchions is a sounder way of doing this. Yeah the sockets could be an issue too; some thick walled tubing sliced to the same length might do better.

As for knowledge, no you don't have to be a Ph.D. in engineering to mod things but also keep in mind that such well working machines like this bike and all the other technology we enjoy is designed with formal methods and accepted practices established over the last hundred plus years of developing all these cool machines so they operate reliably.

Have fun and stay safe
Pete
 
The first time I read this my reaction was: OMG! bending the bars, that's crazy! but as I read more and tried to become more opened minded as its usually my habit, my reaction became: OMG! bending the bars, that's crazy.
 
This is going to turn into a mess of quotes so I will just respond on top:

Good post Pete, thanks for taking the time to write it out.

I believe we really are not that far apart in our opinions, only perhaps the way we express them and the orientation we view them from.

First, I never said this guy's handlebars, the stanchions or anything else will or will not fail. No one can say that with any certainty. What I was trying to get across was the point that now that the bars have been subjected to an enormous amount of stress all the way down to the front tire, and the handlebars have actually been bent, I do not believe they are close to a failure point, nor do I believe there are many little new gremlins (micro cracks, stress lines or anything else you want to refer to) all on the brink of gathering together into an outright member failure (easy boys!). Is it possible, of course. Is it likely, not at all in my opinion.

I have a background in metallurgy and believe it or not ,specifically micro cracks but those caused by hydrogen embrittlement, either from welding (99% of the time) or occasionally a different process such as electro- plating. And yes, the micro cracks all lie in wait until some significant, but far below what would normally cause any type of permenent deformation would occur, stress aligns them and Presto! an outright failure. It has been estimated that when Liberty ships' hulls failed due to underbead weld cracking (in turn from hydrogen embrittlement), the crack speed exceeded 3,000 fps and sounded like an explosion. I also understand creep fatigue and believe it happens. All of that said, I also believe it is a relatively very small failure mode of the world we live in.

Let me give an example: when I was a kid, and I dropped a motorcycle, it usually bent the brake and / or clutch lever. I am sure there were micro cracks around the highly stressed area in an near the bend(s). But in actual practice, I never had a bent lever failure later under anything like normal usage- it either lasted forever (as long as I had the bike) or failed another time the bike was dropped. And I rode dirt with a pile of kids who all had bent levers from crashes and again, never heard or saw one break after being bent but during normal usage- if they survived the crash, they would work bent (and well strained) indefinately (which means as long as that bike was around or until another crash broke the lever in realtime).

As far as fatigue resistance, materials science may well say that aluminum and copper have no fatigue resistance but I disagree when used in the practical world: case in point, copper tubing is used in marine applications because steel would corrode. If copper tubing is used as a direct replacement for steel tubing, in the same way, it will soon fatigue and fail (crack). This is typical for things such as fuel lines. But take the same copper tubing and instead of making a straight line between two fittings, make a 360 degree turn (a full circle) to spread the stress out and poof: the tubing will last for the life of the boat, engine or whatever it is used on. This is a perfect example of the deviation from the taught (and correct) scientific slope that says copper will NOT last infinitely and the practical experience that navies of the world use and simply do not suffer from fatigue cracks when using copper. Nothing fishy here either: we are just getting close enough to the asymptope of the curve as to be 'practically forever' which is close enough.

No need to question that my knowledge has limits, I know only too well that those limitations are all too many and often.

Now, about the mocking thing: I may have been mocking you but really, I was mocking the 'Chicken Littles' of the Internet world, or as I like to call them Mary Jane Tinkelpants because they react like an eight year old girl. Everything could always result in disaster and it may lurk just around the corner. Yeah, yeah, yeah. Could this guy's bars fail- of course. But I do not believe they will for reasons already stated, the great majority of aluminum castings, especially die castings will either fail or survive unscathed when subjected to a great deal of stress, not stand on the knife edge of [almost failed and hanging on the brink] virtually failed. Notice I always put things in posts regarding things like this as "unlikely" rather than "cannot" or "will not"- I do not disagree with you regarding micro cracks, I merely think it is a rare enough thing in 'real life' that I assume it will not happen rather than expecting that it will.

And again, I stand by my original thought: should he check the bars? Maybe. But really, we are all supposed to walk around the bike and check things before every ride but I do not- I assume that both axles will make it through one more day. Just like is done after a bike crash- check all the stressed parts the very best way you can, put whatever 'seems' OK back into service and then forget about it. Your post struck me as suggesting 1) the OP be a bit paranoid about all of his handlebar components from the moment he bent them forward and 2) more attention and time studying them will reveal when they go from 99.5% broken (from micro cracks or whatever else) to 99.8% broken and he could stop using them at that moment. Again, it could happen but I doubt it will.

Have a great day.
Brian

Mid_TN_rider said:
And I mainly commented on this thread because knowing what I know from much experience, I felt like I ought to help a fellow COG'r stay safe.

Take care
Pete
Click to expand...
 
Yep, another terrifying thought- what if compression loads on the sockets propagate cracks through the broaching cuts of the hex (or twelve points) in those sockets? Will the terror never end? :)

As far as bending the bars, I personally would remove them from the bike before trying that. As I previously mentioned, I am amazed that the bars bent before some part of the stanchions snapped off but that is what the man claimed, he has photos and I have no reason to believe he is telling tales.

An even better way to go, IMO as always, would be to cut and weld the bars at the angle desired. Of course that is going to take more than a vice and the will to use it but still, it would give a strong and secure result with the added benifit of having an exact angle that would be the same for each bar rather than 'close enough'. Another plus is that there could never be a possibility of having to bend a bar back to a lesser angle if one overdid it- which is something I would avoid doing (bending a bar one way through deformation and then bending it the opposite way any amount at all).

Brian

LakeTrax said:
Me neither... That's why I asked if they were Snap-On! :rotflmao: I would worry more about micro-cracks developing in the stanchions from over-torquing the stanchion mounting bolts with sockets underneath than from hand-bending the bars while they're mounted to the bike. I'm guessing that if 6-point sockets are used with the 3/8" drive side facing up then you're ok- :)) Seriously though, this is an interesting set-up that I never thought of-

What I learned here is that it may be acceptable to bend the bars on my C14 to my liking if they are first removed from the stanchions? That would at least eliminate the possibility of cracking a stanchion-

Dude, that's hilarious! This is my other favorite scene from that movie-
Pee-wee's Big Adventure - Bike Crash
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Now you see BDF is one of the guys whose mechanical opinion I respect. Given that insightful and gracious post above has made me modify my reaction to bending the bars. Instead of OMG! bending the bars? That's crazy, I would say: Oh my Lord, bending the bars? that's crazy!!

...putting aside the sarcasm for fun...BD 's post made me think of my reluctance to put engine guards again on me bike, in spite of the fact I dropped the damn thing again. I looked at the option of sliders, but the stress on engine bolts upon a 'drop' impact reverberates some of the dynamics on stressing metals that BD is talking bout...well maybe I am stretching it. But that's my story and I am sticking with it.
 
;D

And for whatever this is worth, I would not bend the bars on my own C-14 in the way the OP did. I am merely trying to have a reasonable reaction to what he did, what he says were the results (no reason not to believe him here) and what the future may hold. I never said it was a great idea, merely that the handlebars seem to have survived and I suspect they will live on.... not that they WILL live on. :)

BTW: there have been just a few reports of handlebar failure, specifically the cast stanchion portion of the handlebars, on C-14's. One of them is just down the road from me and uses the same Kawasaki dealer as I do. That particular gentleman reported that not only did he not drop the bike, he did absolutely nothing that caused any stress, including actually riding the bike (!!), when the bars failed and caused him to drop the bike (because the bike literally rolled away while he was holding a handlebar that had suddenly become unattached). This bike was quite new and he had bought it from the dealer new. I never saw the bike, was not there for the failure but did see the pictures of the failed stanchion and they were exactly like one would expect of a failed aluminum die casting- rough, porous metal faces with extremely little bending or material sliding in evidence. My own personal opinion is that either the stanchion was flawed from new (cold joint during mold filling or an inclusion of some kind) or had been previously damaged. But again, I really lean away from the previously damaged thought because the bars would have had to be brought to the edge of outright separation at the flaw line without bending anything, damaging any other part of the bar ass'y such as the bar ends, etc. Of course it is possible that somewhere along the way the bike had been dropped and the obvious damage repaired before the bike was ever sold but I really do doubt that.

And Nando- I was shooting for 'inciteful'.  :rotflmao:

As far as the crash bars, yep there is always some risk that you are transferring drop force away from some things and transfering those forces to other things. In the case of the C-14, the crash bars I have seen bolt directly to the side of the front engine mount and the side of the main frame casting; my own opinion is that both of those points are very well able to take on whatever drop damage those bars can transmit. At some point, the bars themselves will be bent out of the way if the forces are too large and that will actually save the frame..... I believe. I actually bought Canyon Cages for my own C-14, installed the right one but was unable to install the left one due to the position of the Rostra on my bike. So the bars were left off in favor of the cruise control until I can do something about relocating the CC.

Brian


 
BDF,
these are the only two slider options I can find for Ms.Connie

http://www.whaccessories.com/Kawasaki-Sliders-Concours-GTR-1400.htm

http://projektd.com/product_info.php?products_id=71

What is your opinion on these sliders? Do you think it will be easier than with to remove the fairing with either one of these than with engine guard options?

Hear my cry: I had R & G bars which bent the first time I drop it. I drop it twice, the second time it was not my fault.
The R & G bolt to the two long rear engine mount bolts and the frame bolt in the forward position. Now when you take the fairing off you have to remove the R & G which means you actually remove all the engine mount bolt and the engine sits without the appropriate support--now that is not good is it? one could put a jack under the engine to support but then you have to re torque in the appropriate sequence afterwards, but now with the fairing on, a nearly impossible task.

Wiith the Canyon Cagers it you have to use a 16mm rachet wrench which is the only thing that fits in there with the fairing on, to tighten a frame bolt in the forward position.

Now neither one of these options appears to re-assemble the engine mount bolt at the appropriate torque upon removal of the fairing...no wonder I am becoming allergic to engine guards. Plus, no matter how you look at it, them 800 pounds bouncing on those bolts has got to have consequences...ones which no one really knows. Adding to the dilemma, spacers that actually alter the torque value...

I am aware of how emotionally attached we become to things we do to our bikes in the name  of improvements. I had bikes for what seems like 100 years, and I can count with one hand the aftermarket sheet I bought that actually improved something on my bike--the last was Traxxion for a Wing.
 
And BTW, I have seen better **** than this on the internet
 

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Not to go too far offtopic.... I really don't know much about either of those sliders. I have only seen one set of the second you list in person and they were a tad unattractive IMO, and questionable as to whether or not they could absorb much of a bounce. Then again, they are sliders, not crash bars.

For myself, I chose Canyon Cages as the best compromise of protection, intrusiveness (on the bike's lines), cost and function. I do not believe they will cause any damage to the bike if the bike is actually dropped on them as the attachment points are very rugged and the bars themselves have limited strength. The full MC Enterprises bars, or similar types, are used on police bikes commonly and they do not seem to be suffering motor mount or frame damage because of them. But that is what farkle choices are all about- pick the one that works best for you.

Brian

nando said:
BDF,
these are the only two slider options I can find for Ms.Connie

http://www.whaccessories.com/Kawasaki-Sliders-Concours-GTR-1400.htm

http://projektd.com/product_info.php?products_id=71

What is your opinion on these sliders? Do you think it will be easier than with to remove the fairing with either one of these than with engine guard options?

Hear my cry: I had R & G bars which bent the first time I drop it. I drop it twice, the second time it was not my fault.
The R & G bolt to the two long rear engine mount bolts and the frame bolt in the forward position. Now when you take the fairing off you have to remove the R & G which means you actually remove all the engine mount bolt and the engine sits without the appropriate support--now that is not good is it? one could put a jack under the engine to support but then you have to re torque in the appropriate sequence afterwards, but now with the fairing on, a nearly impossible task.

Wiith the Canyon Cagers it you have to use a 16mm rachet wrench which is the only thing that fits in there with the fairing on, to tighten a frame bolt in the forward position.

Now neither one of these options appears to re-assemble the engine mount bolt at the appropriate torque upon removal of the fairing...no wonder I am becoming allergic to engine guards. Plus, no matter how you look at it, them 800 pounds bouncing on those bolts has got to have consequences...ones which no one really knows. Adding to the dilemma, spacers that actually alter the torque value...

I am aware of how emotionally attached we become to things we do to our bikes in the name  of improvements. I had bikes for what seems like 100 years, and I can count with one hand the aftermarket sheet I bought that actually improved something on my bike--the last was Traxxion for a Wing.
Click to expand...
 
Not trying to be argumentative, just to keep a conversation going: A guy who is supposed to be bias to the cop style bars told me, (when I complained to him that the R & G had bent), that engine guards are supposed to bend. He also told me that the Canyon Cagers are too strong. He claimed he saw a cop tear off a frame engine bolt when the cop dropped the bike at a bike rodeo.

I noticed on another thread that Ryan, from MC Enterprise's Canyon Cagers, is looking for ideas to design a new engine guard. I don't know if these things are related but I am taking it all in with a grain of salt.

I looked up the install for cop-style engine guards; and you have to tear a crack on the heat shield inside the fairing, and re-route a radiator hose, plus I could not even conceive the difficulty in having to remove a bunch of stuff in there just to get to the bolt where the engine guard attaches to....that could only means repeating the process every time you take the fairing off...forget about it!

Another red flag on my anti-engine guard rapidly developing attitude. I sure wish the engineer had designed something that is OEM solid right out of the show room.
 
I like the bar risers!  Well done! 

Adding a hardened washer on the socket side would help prevent the socket from digging in the aluminum and provide a little more contact area.

The odd angle the bars are at kills my hands and wrists.  The slight bend you did looks like an excellent fix for that issue.  Not sure if I'm brave enough to try it on my expensive bike but after a bad hand day on a long ride...  I have risers and wedges now and that little tweak in the bars might just make it perfect.

Wish I was not so hard on my hands in my younger days.
 
....and what were you doing with that hand on your younger days...that has worn it out

I too was hard on my hand when I was younger, but all I suffer from is slow peeing...are we talking bout the same thing here? I mean I can still 'clutch' it pretty well...
 
Just for clarification, the sockets are 1/2 inch drive I bought when I put a used Valkyrie  transmissionin in my 94 Goldwing, which I gave to my brother. Here's a photo. I can provide birth certificates upon request!

Here's a photo of the engine going back in.

I hope this clears up the situation about the sockets and bent bars. ;D
But seriously, I understand this mod is not for everyone. I just thought you would find it interesting, possibly entertaining.
 
nando said:
Curious: what made you go from a Wing to a Connie? I had a Wing once also
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Uh, it's like better? ;D While I liked the GW, I love the Connie. Lighter, faster, handles better. Even geared lower (Valkyrie trans), it's a pig in comparison. For 2 up, the wing is better, and his wife rides, mine does not. She didn't fit on his 600. So it's a win win, They ride, and I don't have a wing in my side yard.
 
Brian, thanks for clarifying your points a little more. I guess I'd be willing to say there's little reason to be concerned if it weren't a casting with stress-risors up around the top of the stanchion. Brake levers and such are more ductile; those cast stanchions I think not so much from some of the pictures posted here of ones that broke. Many failures start out as small cracks at stress concentrations during a high load, then once cracked slowly grows as lower stress cycles accumulate because of the inherent stress concentration at the crack. Could be it didn't crack and could be normal use puts such low load on them that even if a small crack started it doesn't grow. I think the point we're not seeing eye to eye on is the stress concentrations. Yes the bars took all the load without coming off, so most of the material was not overloaded, but a stress concentration could cause material at that location to exceed yield or ultimate. I don't know if it did but I tend to share Nando's  reaction.

I agree in practical terms material can be designed to last indefinitely in a practical sense, i.e. well beyond the time anybody might be using a given machine. But there's plenty of test data to show non-ferrous metals don't have an endurance limit, although aluminum can be designed to last 10**7 cycles and the part will only see 1000 cycles a year so then in practical use will last indefinitely or will probably wear out before a fatigue failure occurs. In fact recent research is indicating even steels don't really have an infinite life below the endurance limit. Some people have done fatigue testing to 10**9 cycles and are seeing at least a lower endurance limit at those high cycles; look up VHCF (very high cycle fatigue) if you're interested.

Maybe I'm reacting this way because I was just recently (like a week before Dude posted this) asked to do a stress analysis at work on a part that cracked.  Didn't separate but cracked at a stress concentration, mainly because the guy that did the stress analysis before the test ignored the stress concentration. If we kept using that part it would have broken off and been a lot more expensive problem. So anyway, then I had Nando's reaction; Good Lord! he bent the bars! So I still say err on the side of caution and look at them periodically.

take care
Pete
 
Please take the following in the spirit given, which is one of discussion and practical view rather than one of criticism.

You are on the brink of feeding my very point back to me: steel has infinite fatigue resistance but not really, just nearly. Copper (and aluminum) has virtually no fatigue resistance but some and in certain circumstances, enough. Put this together and it is my very point: copper is commonly used in effectively endless fatigue cycles if only that fatigue is low enough but certainly more than zero. If you are able, take a tour of any US Navy vessel and you will see endless uses of copper with a full loop in it; this has been used for many decades, subject not to thousands but millions and millions of cycles, and is effectively open ended regarding faithful life. So the "rules" are not so much rules as guidelines ready and ably out- smarted by able and clever people who commonly squeeze what is required out of reality. As always, I am not saying that you are not correct for I believe you are, it is just that within that envelope of behavior, while it seems like it has terms that preclude a particular material's use, are limits that can be brushed up against quite successfully.

As to your analysis of motorcycle levers and the handlebar stanchions on a C-14, I respectfully disagree. Unless you know what each one is made from, and I do not believe you (or anyone outside of Kawasaki in Japan), then any speculation on the stanchions being less bendable than the usual levers is simply an opinion backed by no data whatsoever.

Again, just my opinion, but I tend to be more resistant (yep, pun intended) to individual examples of anything. I have seen some truly amazing things in individual cases but do not put too much weight behind them regarding forming opinions. Hey, it took me a long time to believe Bernoulli's principle really, really worked even though I had seen examples. :)

Again, thanks for your measured and thought filled response.

Brian

Mid_TN_rider said:
Brian, thanks for clarifying your points a little more.

<snip>

take care
Pete
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http://www.ebay.com/itm/6538-08-Kawasaki-ZG1400-ZG14-ZG-1400-Concours-Handlebars-Bars-W-Heli-Risers-/400599281074?pt=Motorcycles_Parts_Accessories&fits=Model%3AConcours%7CSubmodel%3A14&hash=item5d4593edb2&vxp=mtr
Hey, here's some pre bent ones on Ebay for $100. The seller makes a point of saying they are straight, but the photo shows the right one is quite bent. He also has 39 negative feedback ratings for bad parts in the last year, so no use pointing it out to him.
Anyway, it's bent lots more than mine without breaking so that's a reality check!
 
Nice find and a great example. Methinks the stanchions are not as fragile or as quick to snap as some of us had previously thought.

And frankly I am still amazed that the stanchions do hold up to that much pressure to bend solid 7/8" aluminum bar stock!

Brian

dude said:
http://www.ebay.com/itm/6538-08-Kawasaki-ZG1400-ZG14-ZG-1400-Concours-Handlebars-Bars-W-Heli-Risers-/400599281074?pt=Motorcycles_Parts_Accessories&fits=Model%3AConcours%7CSubmodel%3A14&hash=item5d4593edb2&vxp=mtr
Hey, here's some pre bent ones on Ebay for $100. The seller makes a point of saying they are straight, but the photo shows the right one is quite bent. He also has 39 negative feedback ratings for bad parts in the last year, so no use pointing it out to him.
Anyway, it's bent lots more than mine without breaking so that's a reality check!
Click to expand...
 
The pictures of the throttle side stanchion appear to show a crack where it receives the round bar. Could be mistaken.
 
gPink said:
The pictures of the throttle side stanchion appear to show a crack where it receives the round bar. Could be mistaken.
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It's hard to tell, might just be a scratch. The tank and other panels are also for sale, all have light scratches. Probably dropped and totaled by the insurance company.. Doesn't look like a high speed crash. I'm telling ya, these bars aren't that hard to bend!
 

Here's something I did a few years ago. I made the air deflectors from Tap Plastic smoked panels, and mounted HD pegs with long bolts thru a chrome socket spacer ;D. I bent part of a HD 3 piece clamp about 45 degrees to make the angle right, and the chrome didn't even flake off or mar! These have been over 100 mph many times and keep your feet from blowing off the pegs (which can really give you a pucker) without damage. Did I mention I like to bend things? And use sockets for spacers?
They were still attached when I traded it for the Connie less than a month ago.
 
OK, some thoughts Brian,

So the "rules" are not so much rules as guidelines ready and ably out- smarted by able and clever people who commonly squeeze what is required out of reality

Yeah, sort of, but these 'rules' are in many design textbooks and tend to be based on test data. To some degree you're right in that the variability in fatigue data is high and is hard to pin down exact design numbers for any given material, which is a good reason to be conservative.

Yeah, I don't really know the material properties of the stanchions vs. say a brake lever; maybe the evidence is more empirical (sort of). We have seen brake levers that bent a lot before breaking off. If you recall pictures of Egodriver71's handlebars after his accident, they broke off without bending very much. They didn't appear very ductile.

And yes copper and aluminum parts can be made for a infinite life if stress is low enough. What you're not mentioning and maybe not thinking of is that the copper on those navy ships is probably fairly ductile. When ductile materials are stressed past yield especially at stress concentrations, the material plastically yields and relieves the stress. And of course if the designers aimed at 10,000,000 cycles for a fatigue life, and they see 1,000,000 cycles in 20 years, then those parts will last longer than the ship.

My gut feeling is that those stanchions aren't that ductile just based on those pictures of the broken ones. And you still haven't addressed stress concentrations. Look on the back side of the stanchions; the casting flash and the cast in lettering and the internal corner at the top are all stress concentrations, which would yield and be fine in ductile materials. I guess those pictures of Egodriver71's bars just make them look not ductile ... OK I found the pictures, here you go, top of the stanchion broke right off without bending (not much if any). I believe a stress concentration in those bars on that bike would cause a small crack instead of just yielding.

Anyway, Brian you're keeping me up past my bedtime and I didn't have a cold one!

cheers
Pete
 
The only hope I have to get back to my regular life is to 'unnotify' myself out of this thread...so long my fellow metal-benders
 
See- we are closer in our thinking than you thought :)

One comment about the brittle stanchions though: I just do not think we (all of us on the planet) have enough data to have any conclusions, at least none based on more than 'gut feeling' (read: educated guess). The problem is the very, very few stanchions that have failed, and we just don't know what caused those failures. As I said before, I am leaning away from the stanchions being brittle and leaning toward manufacturing flaws just because there are so many C-14's out there, so few stanchions have failed, and yet when they do fail they seem to do so fairly easily, at least some of them, and so very quickly. So in my thinking, brittle stanchions fits in fine with the couple of very brisk breaks that some have had but it does not even get close to making sense that more have not broken without severe stress. Going by the early pictures in this thread, maybe even excessively excess stress 'cause the original poster sure got excessive with them IMO.

Brian

Mid_TN_rider said:
OK, some thoughts Brian,

<snip>

Anyway, Brian you're keeping me up past my bedtime and I didn't have a cold one!

cheers
Pete
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Well looks like we lost even Nando. Yes agree, the original poster got excessive with his bars!

I'll just mention that brittle can be strong if not abused or over-stressed. Again I strongly believe that the stress concentrations are what gets you in brittle materials because when "overstressed", cracks form at those locations but the part doesn't break off because the remainder of the material was not overstressed. Just material at one tiny place. I put overstressed in quotes because absent stress concentrations the part would not be overstressed but with stress concentrations the proper design load is reduced so cracks won't form at stress concentrations. Exactly the issue with this part that cracked at work recently.

We'll maybe Nando's right and we should sign off on this one. Good discussion and if anything maybe got people to be more thoughtful before they just start bending stuff

take care
Pete
 

They call me MISTER Bender! (Play on the movie "In the heat of the night", an even better classic than "Peewee's big adventure".
 
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