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2006 C10 Carburetor Cleaning/Rebuild question...

jcaputo58941

Dad3Sons
Guest
Forum gods -

New to me 2006 C10. Cleaning/rebuilding carbs. There is brass fitting adjacent to the main and pilot jet intakes in the float bowl. It looks to be the intake for the starting enrichment circuit. Question: Is that brass fitting a jet that needs to be cleaned or a plug? I cannot get my tiniest wire to penetrate that fitting. Maybe it's a plug and the enrichment circuit gets fuel from higher up in the carb body? Can anyone enlighten me? Thanks!!

IMG_3919 (1).jpeg
 
Success!! Thanks for all the feedback and pointers. I got my Clymer's manual yesterday in the mail. It says the Starter Jet is size 45 for my CA model. Guessing that's 0.45mm, I took a wire bristle fiber from a clean wire brush I had. Short and stiff. It measured 0.32mm. I put it in a micro drill I had from my old RC hobby days.

IMG_3921.jpeg

Then I just started softly drilling and working it in. After several minutes, it was cleared. I sprayed carb cleaner through the circuit and then WD40.

IMG_3922.jpeg

I got all 4 jets cleaned out and am now just waiting for my parts to arrive. This project is moving along!!

Thanks again and will keep you all posted!
 
I'm a little concerned that the 45 represents a flow rate, not a dimensional size.
I think your prolly ok, but did the wire pass thru any of the carbs without drilling?

Also did you get flow thru the upper hole that I mentioned when spraying?

Ride safe, Ted
 
Hey Forum gods -

I got the carbs disassembled, cleaned, new parts, and reassembled. I cleaned and reused the jets from the carb, as the new jets that came from my (probably China) rebuild kits didn't look exactly the same as the ones that came out. At least the idle air needle jets were very differently shaped and not as long. The pilot jets looked similar but were not marked for any ID on size. I was very careful to set float levels so that the float is parallel to the carb bodies. The idle air jets came out 2.5 turns out from seated, and I reinstalled them that way. That left the idle air needle barely protruding into the carb throat. I could just barely feel them with my finger. Anyway, I got it all put back together, and didn't even have to use very many of my swear words, except for the CA emissions tube routing. I also installed new spark plugs, oil and oil filter, and air filter.

Amazingly, it fired right up! The enrichment circuitry works great. It idles great and revs off idle quickly. After getting up to temp, I went for a short 3 mile test ride. Off idle is strong, it gets flat around 3500 rpm through about 5500 rpm and then takes off strong after 5500 rpm. I'm going to do a little more research on how to sweeten up that area between 3500 and 5500 - from about 1/4 throttle to over 1/2 throttle.

So far I have about 6 hours and $75 in parts and oil and filters into the project. The only feature that I can see doesn't work is the fuel gauge so far. Will trouble shoot that this week.

WooHoo!!
 
Hey Forum gods -

I got the carbs disassembled, cleaned, new parts, and reassembled. I cleaned and reused the jets from the carb, as the new jets that came from my (probably China) rebuild kits didn't look exactly the same as the ones that came out. At least the idle air needle jets were very differently shaped and not as long. The pilot jets looked similar but were not marked for any ID on size. I was very careful to set float levels so that the float is parallel to the carb bodies. The idle air jets came out 2.5 turns out from seated, and I reinstalled them that way. That left the idle air needle barely protruding into the carb throat. I could just barely feel them with my finger. Anyway, I got it all put back together, and didn't even have to use very many of my swear words, except for the CA emissions tube routing. I also installed new spark plugs, oil and oil filter, and air filter.

Amazingly, it fired right up! The enrichment circuitry works great. It idles great and revs off idle quickly. After getting up to temp, I went for a short 3 mile test ride. Off idle is strong, it gets flat around 3500 rpm through about 5500 rpm and then takes off strong after 5500 rpm. I'm going to do a little more research on how to sweeten up that area between 3500 and 5500 - from about 1/4 throttle to over 1/2 throttle.

So far I have about 6 hours and $75 in parts and oil and filters into the project. The only feature that I can see doesn't work is the fuel gauge so far. Will trouble shoot that this week.

WooHoo!!
It could be that the aftermarket carb parts is part of the problem. If I were buying carb parts, I would get OEM from Murph.
 
Stock C10s are known for a lean stumble around 2000 RPM and a jump in power around 5500 RPM. Steve (SISF - Shoodaben Engineering) has the solution for both of these issues with his "2 Minute Mod". What I noticed with my 2001 C10 after installing this mod was that the bike sort of felt slower and this was because the missing power below 5500 RPM was filled in, making the acceleration rate smoother - free of the drama.

https://sites.google.com/site/shoodabenengineering/concours-1000-carb-services-and-adv-cam-sprocket

Like you, I went through all the pain and strain to carefully set the carb float height to exactly 17mm. When I measured the fuel level in the carbs it was all over the place and required many cycles of measure fuel height, drain, bend float tang, fill carbs,....rinse/repeat. For optimum running you will need to correct the fuel level. Sorry for the bad news. :)
 
Thanks Brooke. I always appreciate learning from others' experience. I just took it for another test ride - about 10 miles with 3 gallons of fresh gas in the tank. Still very limp from 3500 - 5500 RPM. I'll pull the carb bank again this week. I've watched several of SISF's videos - extremely helpful. Stay tuned!
 
Since this is a 'new to you' bike, I wonder:

1) Do your carb bowls have overflow tubes in them?

2) Did your airbox have a piece of foam blocking off most of one of the intake holes?

3) Do your main jets have the engraved size filed off of them?

If yes to 1) and 3), you may have the 2 minute mod already. The 2MM needs a piece of foam to block off most of one of the intake holes, or the engine will run very weak.
 
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Hey Stasch - "no" to all three questions. I've been researching the 2MM and will probably pull the trigger on that. I want to get the carb bank off one more time. I want to make sure I have all pilot jet circuits and those 4 micro holes in the carb throats at the butterfly completely cleaned out. There was a lot of Sea Foam debris in the float bowls and jet intakes. I thought I had cleaned it all out, but there may have been more in there I didn't get.
 
Status update. Pulled the carb bank off again. Getting good at it now. Double checked all float levels. Discovered the main jets and pilot jets are, indeed, factory originals, properly sized for a CA model bike of that year, and marked appropriately with the ā€œK starā€ for Keihin. Re-clean everything and reinstalled. Bike runs very well now. Still a bit of a lean response off idle but way better. Pausing my efforts briefly to get the title processed thru DMV. Will look into the 2MM for airbox by SISF!!
 
Status update. Finally got the CA DMV process completed. What a mega-cluster...

Carbs seem to be clean and fully functional. Getting used to the power delivery. Weather in my neck of NorCal has been cold and wet on and off. Not getting a lot of miles lately. New CalSci vented windshield. Relocated the coolant overflow bottle to under the seat. Acquired and mounted a $90 Amazon top case that holds 2 helmets. Discovered some farckles from PO's: heated grips (that work), bar risers, electronic taillight flasher system.

Some pics of the project so far.

IMG_4150.jpeg
IMG_4151.jpeg

IMG_4154.jpeg
So far, so good!
 
Looking good!
On the of idle etc. (while your considering the 2 MM) you might try raising the needles slightly.
Less work than pulling the carbs and might work out (richen off idle) because of the Calif. Jetting.

To do the needles, you'll need to find tiny washers to raise the needles.
EZ to get to the needles as all you have to do is remove the top of the carbs and access the slides.

Ride safe, Ted
 
Status update. Finally got the CA DMV process completed. What a mega-cluster...

Carbs seem to be clean and fully functional. Getting used to the power delivery. Weather in my neck of NorCal has been cold and wet on and off. Not getting a lot of miles lately. New CalSci vented windshield. Relocated the coolant overflow bottle to under the seat. Acquired and mounted a $90 Amazon top case that holds 2 helmets. Discovered some farckles from PO's: heated grips (that work), bar risers, electronic taillight flasher system.

Some pics of the project so far.

View attachment 35336
View attachment 35337

View attachment 35338
So far, so good!
You might post a link to the trunk for those who could be interested in buying one.
 
Here's the link to the Comie 48 L top case.

Comie 48L Top Case

I mounted it with a couple of 1" square rails like "bike1918" did in the C10 Accessories Thread here. It's the same top case "bike1918" installed.

It will hold 2 helmets.

IMG_4159.jpeg

IMG_4158.jpeg

IMG_4155.jpeg

Ted - My brother suggested the same thing about raising the needles with washers. That will be the next tweak!
 
So I "winged" an installation of SISF's 2 Minute Modification - the air box intake foam wedge. I found a new/unused tiler's sponge in my garage's bag of tricks and cut off a 2-1/2" long hunk. I stuck it in the right side air box intake snorkel. It blocked off about 2/3 of the intake frontal area. Then I went for a test ride.

The result was unbelievable! Instant midrange torque! The flat spot passing through 3500 rpm was completely gone and the bike pulled smoothly through 5500 rpm! It's amazing how providing a small air restriction could have that much influence on the operation of the CV carbs. I suppose creating more vacuum causes a quicker and greater lifting of the carb slides. SISF is a genius!! So much happier with the C10's power delivery!
 
So I "winged" an installation of SISF's 2 Minute Modification - the air box intake foam wedge. I found a new/unused tiler's sponge in my garage's bag of tricks and cut off a 2-1/2" long hunk. I stuck it in the right side air box intake snorkel. It blocked off about 2/3 of the intake frontal area. Then I went for a test ride.

The result was unbelievable! Instant midrange torque! The flat spot passing through 3500 rpm was completely gone and the bike pulled smoothly through 5500 rpm! It's amazing how providing a small air restriction could have that much influence on the operation of the CV carbs. I suppose creating more vacuum causes a quicker and greater lifting of the carb slides. SISF is a genius!! So much happier with the C10's power delivery!
If that worked then possibly your bike had the 2 min mod and the foam was removed at some point . Steve's mod includes different jets so it should have run poorly with the stock jets and foam . Do the carbs have overflows ?
 
Hey Cra-z - Best I can tell the carbs and jetting are bone stock. No overflow tubes. #35 Keihin pilot jets and #130 Keihin Mains for the California bike. All I know is it runs way better with the foam/sponge than without. So what size pilots does SISF use? Or is that a trade secret?
 
Hey Cra-z - Best I can tell the carbs and jetting are bone stock. No overflow tubes. #35 Keihin pilot jets and #130 Keihin Mains for the California bike. All I know is it runs way better with the foam/sponge than without. So what size pilots does SISF use? Or is that a trade secret?
Pretty sure it is a trade secret .
 
When Steve was developing the 2MM, he started by restricting the air flow as you did to test his theory.
Worked fine, but the bikes had poor mileage.
So he developed the jett sizes that are in his kit.
As you have a Calif. bike, you already have smaller jetts than most of the C-10 bikes in the USA.
So, watch your mileage. If it's ok, your close to perfect.
BUT!! you need (and don't have) the standpipes/overflow tubes in the carbs as they protect from Hydrolock.
 
As you have a Calif. bike, you already have smaller jetts than most of the C-10 bikes in the USA.
Surprisingly, its actually the reverse.

The OEM CA mains options are bigger than the 49er's.

I'm sure there's a good reason for it, but it doesn't seem intuitive.

Go figure.
 
Iā€™m a 4th generation CA native. In my 66+ years, Iā€™ve witnessed so many things in the last 20 years in this state that were unthinkable in my first 46 years. But thatā€™s another topic for a different forum. :rolleyes::cool:šŸ™ƒ

Iā€™ve had more fun in the short 2+ months on this Concours bike project. I really appreciate the knowledge and support of this group!

My fender extender showed up yesterday! Another task awaits!!
 
Short status update of this project. I got the engine sorted as noted in the posts above and the engine runs great! The battery died and I just replaced it. Also replaced the tires.

After reading everything I could find on the forum, I settled on the Shinko 733/734 series touring tires. I got the stock size for the front and the Wing size for the rear. What is difference new tires make! The bike came with Metzlers that looked to be in good shape but were date stamped from 2013 and 2014. The rear was actually not too worn but the front was in terrible shape. I was able to change the front tire, but took the rear wheel assembly to a local shop and they R&R'd it for me.

The new Shinko's are smooth, neutral steering, very predictable and greatly reduce the effort required to move the bike around. This bike is really growing on me! It's really fun to ride!

Two remaining issues: I went for an evening ride today and discovered about half of the backlighting bulbs in the instrument cluster are out. Will attempt to remove the instrument cluster later this week to replace them.

Also, The fuel gauge doesn't indicate "Full". As full as I dare get the tank, it only indicates about 85% full (below the white gauge limit). Anyone else have that problem?

Thanks!
 
Short status update of this project. I got the engine sorted as noted in the posts above and the engine runs great! The battery died and I just replaced it. Also replaced the tires.

After reading everything I could find on the forum, I settled on the Shinko 733/734 series touring tires. I got the stock size for the front and the Wing size for the rear. What is difference new tires make! The bike came with Metzlers that looked to be in good shape but were date stamped from 2013 and 2014. The rear was actually not too worn but the front was in terrible shape. I was able to change the front tire, but took the rear wheel assembly to a local shop and they R&R'd it for me.

The new Shinko's are smooth, neutral steering, very predictable and greatly reduce the effort required to move the bike around. This bike is really growing on me! It's really fun to ride!

Two remaining issues: I went for an evening ride today and discovered about half of the backlighting bulbs in the instrument cluster are out. Will attempt to remove the instrument cluster later this week to replace them.

Also, The fuel gauge doesn't indicate "Full". As full as I dare get the tank, it only indicates about 85% full (below the white gauge limit). Anyone else have that problem?

Thanks!
Replace the bulbs with LED bulbs. The fuel gauge is notorious for being pessimistic. The addition of a resistor across the sending unit wires helps correct that or you can bend the float rod.
 
Fuel gauge mod .

I've always just bent the arm on the fuel gauge sender on all my C-10s. My fuel meter reads perfectly accurate as I approach the point on the meter indicating I should be going on reserve.
 
Replace the bulbs with LED bulbs. The fuel gauge is notorious for being pessimistic. The addition of a resistor across the sending unit wires helps correct that or you can bend the float rod.
Buds right on about replacing with less, did that way back when I had my c10. Thought there was a thread on yhe forum, or maybe it's in yhe tech section, that tells you what where who about the bulbs. I replaced all the bulbs on the dash, turn signal,.bright light, neutral and all the back lighting bulbs..
 
Search lights for tach and clock. In the thread someone posted part numbers, quantity and cost.. post is 2 years old iirc..
 
I used led bulbs from superbrightleds.com The background lighting is green 4 ea 194-g5: green bulbs. The clock is the (1) 74-ghp: green. The indicators are the 194-g4 in green, blue, and red. I found that the high beam indicator was too bright with 194-b4-90 so I have now replaced it with the 194-B-90: blue 90 degree it is a lower wattage bulb and not as bright. The part numbers are off the receipt when I bought them in 2017, and 2019. I had to search around their site a while to fine the ones I wanted. People have used blue and white for the background also.

Remove the windshield, then the instrument cluster. The bulbs are removable from the back. Test the lighting before you bolt the instruments back in, some led only work if installed the correct way. If it doesn't work remove the bulb turn 180 and reinstall.

174-GHP: Green$1.95
4194-G5: Green$3.49
3194-G4-90: Green Wide$2.59
1194-B4-90: Blue Wide$2.59
1194-R4-90: Red Wide
2194-B-90: Blue 90 Degree$0.99
 
I've always just bent the arm on the fuel gauge sender on all my C-10s. My fuel meter reads perfectly accurate as I approach the point on the meter indicating I should be going on reserve.
I did the same. Just bend the arm slightly and you're done.
 
Maybe I got lucky with the resistor mod but as soon as my gauge hits red I need to go to reserve . Before , I could ride on red for quite awhile before hitting reserve . No more guessing and watching the trip meter . I like it .
 
As I recall, you have to bend the float down.

Once the sending unit is removed you'll see that there is a bend in the wire that the float is mounted on.
There is to much bend in the wire. (which is why the gauge reads empty too soon)
So, I straightened the bend slightly. (to lower the float)

How I bent and gaged the amount of Bend;
When I did my first, I drained the fuel until the fuel level was at the point of going to reserve.
I removed the tank and set it on its side (fuel side down), and then removed the sending unit.
I traced the bend in the wire on a piece of paper, then straightened the wire a bit and retraced the bend over the first.
Then I re-installed the sending unit, mounted the tank, and hooked it up.
Then turned Key on, and read the level.
I repeated the process as needed until the bike goes on reserve just as the needle reaches the "bottom" of the red.
Took me about 3 tries to get it exactly where I wanted it. I used the tracing to bend future floats.

Update; Seeing Mikes chart, I think he's right on the direction of the bend. I had a similar chart when I did mine.

(Please don't tell him I sed that). o_O

Ride safe, Ted
 
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Attached is my guide for bending the fuel gauge sender arm that I developed in 1998 for C-10 #1. Bending the arm so it conforms to line #3 will allow the fuel gauge to just be hitting the red reserve mark when you will have to switch the petcock to reserve. I'm on C-10 #4 and this graph has allowed me to adjust the arm exactly where it needs to be on all my subsequent C-10s without trial and error.

1686097542245.png
 
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COGger's - I haven't posted for a while - I parted company with my C10 in June. I couldn't pass up the offer. I do miss it, but shortly after selling it off, I found a 1996 BMW K1100LT. Learning it's foibles now.

I'll stay in touch with the COG community. Who knows, maybe there will be a C14 in my future...

Take care!

Joe from NorCal
 
Attached is my guide for bending the fuel gauge sender arm that I developed in 1998 for C-10 #1. Bending the arm so it conforms to line #3 will allow the fuel gauge to just be hitting the red reserve mark when you will have to switch the petcock to reserve. I'm on C-10 #4 and this graph has allowed me to adjust the arm exactly where it needs to be on all my subsequent C-10s without trial and error.

View attachment 36104

Commenting to save this graph. šŸ˜
 
Commenting to save this graph. šŸ˜
Since having C10's since '03 I had never tried bending float arm to tune gauge to fuel level. Just always learned how each bike runs and watched trip odometer. I had seen this graph you had referenced, made a copy and today the fuel level was low so made the executive decision to try. Made it match his lines, hooked all up and went for a ride. BAM!! As soon as the gauge needle hit red it sputtered and had to go to reserve. For me the graph lines for the float arm bend are perfect. Thanks for bringing this topic back up!!
 
ā€œThanks for bringing this topic back up!!ā€œ

Youā€™re welcome Roger.

I will DEFINITELY be making the mod this winter ā€¦ā€¦
I rode around ā€œin the redā€ all day yesterday, going to and from the Devils Stair Case.



(Fortunately itā€™s only 5 miles from my house)
 

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Since having C10's since '03 I had never tried bending float arm to tune gauge to fuel level. Just always learned how each bike runs and watched trip odometer. I had seen this graph you had referenced, made a copy and today the fuel level was low so made the executive decision to try. Made it match his lines, hooked all up and went for a ride. BAM!! As soon as the gauge needle hit red it sputtered and had to go to reserve. For me the graph lines for the float arm bend are perfect. Thanks for bringing this topic back up!!
Glad to hear it worked as well for you as it does for me.
 
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