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2002 + 3 circuit carburetor pictures ,info and cleaning process

Started by Armandorf, March 07, 2023, 12:07:40 AM

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I am currently in the process of cleaning my 2008 carb.
Took pics.
I noticed the sticky has dead pictures.
I plan to edit this comment and make my how-to clean and put info regarding carbs and internal parts.


Very important: do everything in a clean and controlled environment, with good light and space. if you do this over the grass you risk losing parts.
I prefer to put the carbs on my desk and stink the house rather than losing inside bits.
Purge the bowls so there is as little gas as possible before opening.

Change JIS screws for allen bolts. , they are like phillips but have a little dot. they strip easily without a JIS screwdriver.  It will be easier to disassemble for next cleaning if you change them. If you are having issues use impact tool,vice grips or cut a slot to extract them.

Remove all rubber parts before using carb cleaner.

Top part:
After removing the top.
Be very careful with diaphragms. I don t take them out of the plastic slide, prefer not to force them. don't lose top cap orings, watch out if they stick in the caps.
Take out diaphragms and put in a safe place momentarily.

Bottom part:
Don't try to remove bowl gaskets if you are not willing to change them.

Floats are held by one screw, they can be cleaned with toothbrush and detergent, hold them by the part you are cleaning and dont flex them or they willl break.
Don't spray them with carb cleaner.

Mixture screw:
Count mixture screw turns so you dont lose the adjustment. Change oring.
if it is still tapped, un tap it(there are various threads about it, you basically run a drill bit ,then you force a  screw and use that screw as leverage to take out the press fitted bronze cap) so you can change the oring inside and clean the passage.

Spray carb only when everything is dissasembled and rubber is out.

Spray jets aiming to a bowl and use the propelled liquid to soak them. i do it on the bowl, but beware of the gasket.
#60 jets and 130# are identical, be careful not too mix them.
Spray every passage. Run thin wire or guitar strings if you can.
Use compressed air if you can.

Q-tips are dangerous( yes , it leaved a bit of cotton inside my mixture screw in the last cleaning). you can use them in the bowls/carb body with caution.
It s better to use shop towels around a tooth pick or other soft material. insert and twist.

Be careful removing needles,i remove them while having the diaphragms mounted on the carb so its stable.
Pull out and rotate as you do so, very straight.
Slide  black plastic clips break and slides are not cheap(i ve been there,sadly)
If needle retainer is too hard to remove, changing the oring can solve the problem.I would change it anyways so it isn't hardened and the clips will not be as forced =will live more.
Also dont lose the coil (if you lose it you can use a pen coil temporalily).

Bronze parts can be polished with fine steel wool if they are looking corroded or too dirty. i polished the valve float seat.
Check the float valve with gas , you can also puff through the hose.

You can check the bowls are moving together on both carbs by rotating the carb body while sitting in a flat surface.  also check the float level.
Don't polish aluminum parts, only bronze. Scratches ruin the finish and the dirt may collect even more afterwards.

Use the ceiling or a bright part of the sky to eyeball jets. make sure its clean,shiny and round in the inside.
in my case i had to run twisted steel wool on the inside of the difusser and bigger jets, and i would not advise it. with a tobacco pipe cleaner or twisted shop towel around tooth pick and carb cleaner you should be good.
Carb cleaner should be enough,. for me was notenough, but oxide was coming down from my 30yr old tank.

if you are having problems check the jet numbers and needle code,  it may have been changed before.
Mixture screw starting point is 2,5 turns out from lightly seated(all in) position. if you are over 4 turns out you need a bigger pilot jet.

in my case i have a 5DH60 needle with 17.5 pilot, 60 mid, and 130 mains.
Changed the pilot to 20. I drilled 130 to 140, waiting for main jets that i ordered.(correct jet is better than drilled)

Oring list. x2 You can buy them in a oring store if you cant get the OEM ones or they are too expensive.
+top caps
+needle retainer
+main jet
+mixture screw
+float bronze seats(if you remove them)
+intake boots(carb engine side to cylinder head) orings flatten out, change them. they cook, use Viton.
i used a impact tool to remove the bolts and it came out in 1 minute. or use your creativity.
Changed the screw to allens

-Tightening the cam chain tensioner and putting loctite is not a bad idea. without the carbs is easy to do so.
-Also check exhaust bolts, i lost a pair.
Consider running an inline filter for gravity fed systems, most car filters are designed for fuel pumps.

needle and jet chart by @ben2go
pending image insertion


I have cleaned them several times and it's a pity the forum doesn't have this info up to date.
I hope this is will be handy and make the first opening of the carbs less frightening.

Also plan to include links of interest of other threads here from other users and the blog written from @mr72.



Any contribution is welcome and I will also need all of you to check the post is right and improve it.

Special thanks to @The Buddha for helping me out previously and all the community.
sorry for my write up.its a bit messy.


Thanks for taking the time to do this!

I'm currently working on my carbs from a 2006. Your pix were really helpful!
2006 GS500 Naked Touring Bike

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