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Jerky shifting

sycamoredavid

sycamoredavid

Tricycle
I've ridden mostly Harleys all my life, but I just got an 09 C14. I love almost everything about it, but I'm have having a hard time getting used to shifting. Mainly from 1st to 2nd and 2nd to 3rd, it is very jerky. I have tried several different methods and techniques to resolve this,but can't seem to find a solution. I never had to even think about the shifting on my Harleys. Is something wrong with my bike? Is this just normal for sport bikes?

Thanks for your thoughts!

Regards
-Dave
 
Dave said:
I've ridden mostly Harleys all my life, but I just got an 09 C14. I love almost everything about it, but I'm have having a hard time getting used to shifting. Mainly from 1st to 2nd and 2nd to 3rd, it is very jerky. I have tried several different methods and techniques to resolve this,but can't seem to find a solution. I never had to even think about the shifting on my Harleys. Is something wrong with my bike? Is this just normal for sport bikes?

Thanks for your thoughts!

Regards
-Dave
Click to expand...


Same here buddy. Just got mine and I felt the same thing. I've found that if I stay in low rpm's or use some power to shift through it's not so bad. I guess it's the shaft drive. Don't feel normal to me. It will be interesting to here the replies for sure
 
Modern Fuel injected bikes have a pretty annoying quirk that the power is pretty much like a light switch, instant on and instant off (Very jerky)  Takes some practice but you will eventually get smooth shifts (Took me a thousand miles or so)  Also adding a G2 throttle tamer helps bigtime IMHO
 
The C14 is silky smooth compared to a HD. I recently rode a softtail and the gearbox was crunching and banging and clanging. I asked if that was normal and everyone said yep.

I'm sure your just getting used to the bike. Other than engaging 1st from neutrel, every other change should be smooth. Easy up on the throttle and use more clutch. It will come good eventually.

If it doesn't, then something else must be wrong.
 
I have had my 08 since July . For a while my shifts were jerky. Now I can shortshift through the intersection, and hit third on the other side, slick as a whisle .
sometimes I still clank one

Keep the shiney side up

Chuck
 
What is the idle set at? The C14 is a little jerky in the lower gears anyway. But it is magnified if the throttle is set too high. Also if the flies are removed. You might try being slightly slower when going back to the throttle. A slower roll on helps some also.
 
Along with all of the above, too much slack in the throttle cables will magnify the effect also.
 
Tactical_Mik said:
Along with all of the above, too much slack in the throttle cables will magnify the effect also.
Click to expand...

What Mik said, take up almost all the slack in the throttle adjuster screw, and get a throttle tamer, that should cure the problem, and also the idle as has been mentioned.  Too low and it will make the shifting jerky also.
 
Thanks for all the replies. I had read elsewhere on this forum that the throttle cable needed to be properly adjusted so I have already tried that. I'll check the idle to make sure that's ok. I can usually avoid the jerkiness if I am slow to apply throttle after shifting. It just doesn't seem like i should HAVE to do that. I never did on my Harley. I'm not sure about the butterflies being removed. I bought this used, but the previous owner didn't mention this. How can I check to see if they have been removed?

Thanks!
Dave
 
Dave,
keep in mind that these motors work very differently from a vtwin.  I came from a Vulcan and can relate.  On the vulcan, my shifting was "sloppy" in that I didn't have to be as concise with matching the throttle and clutch in order to make for smooth shifting.  it's a skill that has to be learned.  I don't know if you've read Rider magazine at all, but I still recall an article that Clement Salvadore wrote about the need to practice the skill to be proficient at it.  I've found it most helpful to shift quickly.  the good part is you get to practice that skill on a GREAT bike!  :)
 
kawi has 2 sets of throttle plates on the throttle bodies,  one set of plates is tied to the throttle cable and opens when you twist the throttle,  the other is controlled by a stepper motor and the ECU and are usually closed at low RPM's to make the low end grunt a bit more tame.    Some people remove those flies, and add a power commander which really wakes up the low end grunt of the motor...
 
Trouble said:
Quote -  I'm not sure about the butterflies being removed.  End quote .

WTH are butterflies ?
Click to expand...

Trouble, I was referring to Capn Bob's comment on the "flies" being removed (which is short for butterflies).

-Dave
 
Trouble said:
Quote -  I'm not sure about the butterflies being removed.  End quote .

WTH are butterflies ?
Click to expand...

Here is a picture of "butterflies"  There are four of them and they are the gold colored round things in the throttle bodies.  Those are the butterflies that people remove.  BTW that isn't a picture of a C14 but a ZX10R but they look almost the same on the C14

IMG_4301.jpg
 
Trouble said:
What would be the logic of removing them ? The factory put them there for a reason I would guess.....
Click to expand...


Yes the factory put them in. They do smooth out the motor. But they also act like a restriction on the motor. The C14 is OK at low end in factory form. But removing the flies and adding a power commander really increased the low end power (say 2K to 4K). It makes a big difference in the bikes low end power. But it also makes the throttle more abrupt.
 
COGnosticat0r said:
Trouble said:
Quote -  I'm not sure about the butterflies being removed.  End quote .

WTH are butterflies ?
Click to expand...

Here is a picture of "butterflies"  There are four of them and they are the gold colored round things in the throttle bodies.  Those are the butterflies that people remove.  BTW that isn't a picture of a C14 but a ZX10R but they look almost the same on the C14

IMG_4301.jpg
Click to expand...


Just to point out. This is not exactly how the flies look on the C14. On the C14 the metal plates (flies) are mounted on top of the rotating rod, with the screws heads visible on top. This looks to be the opposite on this ZX14 ZX10 pictured here. So other than a similarity, this really isn't how they look. Not to mention the view of the area involved is also totally different. It's not this big wide area as seen in this picture. There are two small access area's that you must go through on the solid C14 frame. So in reality, this picture as totally different than the C14 other than it having four flies of a similar design.

This wasn't meant to knock anything. Just to point out that the picture is of a different similar fly set up. Although Jerry did state they were from a ZX10 and not a C14.
 
My ZX14 is not jerky at the throttle. It did have a bog off idle which got fixed when I put a full exhaust (CT-Duals, Brock's) and piggy on it.

Removing the flies does, on the ZX14, contribute to removing the bog off idle, so makes it feel smoother. But the secondary butterflies are used by the traction control, and this is now true of the 2012 ZX14R too. Removing them is a bad idea.

I can feather the clutch and hold it just off idle now, and roll along at 2-3 mph all day long. Or until my hand goes to sleep from holding the clutch.  A couple of God Bless America runs from here to the VA Medical Center in Martinsburg WV was enough to teach me to control the beast at super-low speeds. Almost 3,000 bikes on a U.S. highway going 5 mph at best, and stop and go at worst, all the way down the 20 mile route.

Practice makes perfect.

Also perfected the throttle from riding mountain roads and twisties in general where a lot of corners are 1st and 2nd gear work until apex (i.e., on entrance).

Practice, practice, practice.

Your C14 variable intake cam might make it slightly more hesitant off idle, but I'm thinking the Guhl or Dynotronics or ECUnleased ECU re-flashes would do a lot to smooth it out by opening the secondaries really early.

I guess I will actually know what I'm talking about after I get my C14 and ride it for a season. For now, I'm just taking a wild guess.  :beerchug:
 
ALSO,

Most Harleys use cable operated clutches and the C14 uses hydraulic actuation. There's a big difference on the release/engagement curve between the two. You'll get used to the differences eventually.
 
+1  I was thinking about that today while I was riding at lunchtime as well.  Even with my vulcan experience, it was hydraulic, and I suspect the feel of the cable clutch makes for even more difference.
 
There's nothing wrong with your bike Dave.  Although many people have offered their opinions, none have hit upon the reason you find such a discrepancy in the shifting of a Harley and that of a C14.  In my opinion the main culprit is the weight of the rotating mass we'll call a crankshaft.  The Harley and other big twins have long strokes compared to an inline four with a similar displacement so their flywheel mass is considerably larger and heavier than a four's.  The larger crankshaft cannot accelerate or decelerate nearly as fast as the four's more compact crank.  The C14 also has a much higher compression ration that will also quicken the acceleration and deceleration of its crank.  When you disengage the Harley's clutch while you simultaneously close the throttle to upshift, the engine will slowly lose rpm's and be turning at nearly the correct speed to match the next higher gear when you engage the clutch and open the throttle.  The result is a nearly seamless shift that will not be noticed.  The same holds true with a downshift, disengage the clutch, blip the throttle while shifting and the slow revving crank will again be at close to the correct rotating speed to match the lower gear's required rpm.  Another shift that will not be noticed or remembered. 

Now get on the Concours and you have entered an entirely different realm.  The rotating mass is very light by comparison and this engine's higher compression will combine to give the crank very high rates of acceleration and deceleration.  Now when you upshift, the crank will be rotating at a slower pace than what will be required to accommodate the next higher gear by the time it is engaged.  When you apply a bit of throttle to bring the crank up to the proper speed, you find that a little bit goes a long way because of the crank's rapid acceleration.  Finding the happy medium where the input and output gears are turning nearly equal rpm's when you engage the clutch is no easy task. 

If you short shift the Concours as Ripper suggests, the problem is not as prevalent.  Same goes for running it way up the rpm scale, where the shifts are much easier to make smoothly.  The higher gears don't pose much of a problem, but the lower three gears are difficult to shift without notice.  This problem is not as prevalent with smaller sport bikes as their engines are normally run at higher rpm's than those of the larger C14 and XR14.  Sport Rider's move to a C14 from a Vulcan resulted in similar difficulties making clean, seamless shifts.  His advice is valid, it will take you a bit of time to adjust your reflexes to an entirely different way of shifting.  Mad River Marc also offers a valid piece of advice by suggesting the G2 Throttle Tamer.  With this device the first few degrees of throttle rotation will result in much slower opening of the butterflies and reduce over revving the engine when shifting either up or down.

Having the throttle cables adjusted with as little slack as possible will also be helpful, as it is on any bike.  As for determining whether or not the secondary butterflies have been removed, I would start by calling the person you bought it from and asking.  If that isn't possible then you will have to follow the advice given and look for yourself.  However, I don't think that this problem is a result of the butterflies or the lack of them.  I had the same difficulty shifting the lower gears smoothly after removing the butterflies as I did when they were present.  Fuel injection or carburetors don't enter this picture either.  Nor does the shaft drive versus chain/belt drive suggestion.

As an example of comparing this inline four with another inline four of another make and vintage I can give you my experience with a '79 Yamaha XS11 that I still own and ride.  My C14 is an '09 with the butterflies removed and a Dynojet Power Commander V installed.  Shifting the two bikes is an experience very similar to your experience with the two bikes you reference.  The Yamaha has a heavy rotating mass, low compression and is slow to accelerate or decelerate its crankshaft.  Shifting it is a piece of cake.  I ride the Concours about four fifths of the time and the Yamaha the other fifth.  Each time I get on the Yamaha I am amazed and delighted with the ease it matches its input and output gear speeds.  Something I never noticed until I bought the Kawasaki.  The actual shifting of the two transmissions are also quite different.  The Yamaha's gears don't mesh as smoothly as the Kawasaki's do.  The C14's transmission is light years ahead of the Yamaha's.  However, the instant acceleration and deceleration of the C14's rotating mass makes it a bitch to shift smoothly until you have acquired time in the saddle. 

I am offering this opinion in the hope that a basic understanding of the reason for the shifting discrepancies between the slow revving V twin and the very rapid revving inline four will help you and others adapt to the very different shifting characteristics of the two designs.   
 
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