Rebuilding carbs . . need advice

[mfarrington]

First time, have help from mechanic friend. XS80G carbs, going to break down all the way and soak. Please offer suggestions for seal and rebuild kit manufacturer, plus whatever else comes to mind.

Thanks!

[psycoreefer]

Don't soak the bodies unless you first remove the butterfly shaft seals. Dipping the carbs will ruin the seals and then you will have to replace them. Usually the bodies clean up ok with just spray cleaner and compressed air.

I don't know where to get the butterfly seals if you want to replace them, I'd guess yamaha would have them. I liked the kits I got from georgefix on e-bay, included upsized main jets at no extra cost. Otherwise you can again go to your local shop and order genuine Mikuni jets. Then you'll still have to order bowl gaskets.

Really, unless the carbs are super gunky you probably only need new float valves and seats and bowl gaskets.

Make sure you synch them after the rebuild and spend some time dialing in your idle mix. You can find directions and helpful tips in the tech tips section...

[bikerphil]

I've never used it, but a good friend of mine dipped his carbs in the Yamaha Carb Dip and they came out immaculate. This product is diluted with water and won't eat away those butterfly seals.

[tinman905]

What I have found best is tear the carbs down soak the carb bodies ,main jets, idle jets, emulsion tubes and pilot jets in carb cleaner for a few days if you have the time. I use a ultra sonic cleaner also because I have one . Check that all passages are clear using compressed air . I use acetone on a cloth and wipe down the carb slides avoiding the diaphragms.

The kits from George's on E bay are good they have everything you need except seals in the kits but you can buy new butterfly shaft seals from Mikes XS .com . For the extra time and little cost it's better to completely rebuild with new seals . If you're not sure about doing it yourself clean one at a time it's really not as difficult as you may think.

[tarzan]

I disassemble mine down to the body and leave the butterflies in.Then I hang the body in chem dip so the seals are above the cleaner.That puts all the critical
orifices in the cleaner.Also the small parts fit in the basket in the bottom.I let it soak while I clean all the little pieces that you cant soak,then pull the body out and scrub it down with a tooth brush and spray it off with spray cleaner.I then take all the parts to that carb (and this is the part the little woman hates) and put dish soap and water in the sink and wash everything again.Then its back to the garage and blow the parts off with air as well as the carb body.
I then disassemble the next one and....................

[TopCatGr58]

I've never used it, but a good friend of mine dipped his carbs in the Yamaha Carb Dip and they came out immaculate. This product is diluted with water and won't eat away those butterfly seals.

Hey Phil,

One of the guys on the Yahoo group got the NEW Yamaha cleaner, saw the instructions to use WATER, and it ruined a set of his carbs, at least it made the bodies look all corroded and such. Mark Burns is his name, a very knowledgable fellow around bikes. He had used the Yamaha stuff before but it was when it was mixed with GASOLINE.

He got another can of it, and used GASOLINE and it worked just fine!!

I've never used it, only used the Chemtool Dip stuff, but never dunked the whole bodies into it!!
T.C.

[bikerphil]

Hmmm, very interesting, I'll have to do a bit more research on it. Thanks for the warning.

[81xsproject]

I read a write up on the stuff in Motorcyclist Retro and they raved about the stuff.

[fredintoon]

If you are going to replace the butterfly shaft seals remember that the screws that hold the butterflies onto the shaft have been peened over to stop them falling out and getting sucked into the engine. You will have to drill or Dremel the screw tails off to unscrew them and on re-assembly put new screws in and peen their tails.
As I understand it, the Yamaha carb cleaner used to say "mix 50% with gas" and
only the label has been changed, not the cleaner.

[newc4]

If you can't find the seals here's an interim fix for buttefly seals.

Quite some time ago when I was first working on my carbs, I immersed one in carb cleaner for a couple of the days and the butterfly seals did swell such that the spring wouldn't return them.

Then I recall someone saying brake fluid causes seals to shrink. A little dab with a Q-tip and viola, the seals shrunk. I've done the propane check and they don't leak.

Though not an optimal solution it is an expedient one.

Darrell