carb confessions

[speedlimit85]

I have never removed the carbs for cleaning tuning sync. I have only replaced needles and seats from under and on this bike the all important rubber passage plug.

Today I asked a mechanic if he would clean the carbs and I said the idle keeps dropping. He sprayed choke cleaner on intake and it jumped.

I plan to, for the first time, remove the carbs. I will fix the intake leak and give him the carbs to clean.

Any advice on carb removal?

Do I need to replace the intake boots, just some o-ring or what to fix the manifold air leak.

[Socer4m]

Hi Speedlimit, do a search for carb cleaning in the search section,,,lots of info, but before you do that,,,,get the bike running, spray some carb cleaner or instant start in the front of the carb boots, backside, and locate which carb boot is leakiing. Maybe just tighten down the bolts to the leaking intake, then spray again. The idle adjustment is in the middle underside of the carbs, screw clockwise to speed idle up if too low, use a flat screwdrive if hot or fingers if cold...the rubber intakes last forever, if cracked smear some black rtv over exterior to cover up the cracks, also tighten the carb clamps as that can cause idle problems if loose,,,,,,,,,,
,,if the carbs were running good except for a low idle they do not need to be cleaned,,,,just adjust the idle screw first and check the boots. If all else fails,,,,pull the carbs, follow the cleaning procedures in the search section, tighten the rubber boots, and try to enjoy what every xs owner has to do sometime is cleaning the carbs, sometimes multiple times. good luck and keep us informed,,,,Mike in San DIego and Pa.

[speedlimit85]

Thanks. I will check and tighten the boots first.

These boots are from mixes xs about 7 yrs ago and 30,000 mi.. If I do replace, they will be partzilla.

[Socer4m]

HI, 7 years is not old for boots,,,,so keep checking for leaks, tighten up the clamps, adjust the idle speed screw and pray for the xs gods to be good to you,,,,,,

[Schming]

Check to see if the carb boots (engine side) have gaskets, if so they don't last long from the heat. I among others don't use them but smear a thin layer of Yamaha-bond 1104 in place of the paper gaskets and have never had a leak. Be careful not to over torque the bolts. Also check the brass vacuum tubes on the boots as some come loose.

[Radioguylogs]

In addition to the intake manifold boots, the butterfly shaft seals can also cause a vacuum leak. It happened on my 1979 XS750 (same carbs).

[speedlimit85]

I see leaks on all 4 to the metal. These are the paper gaskets from mikes xs and are shot. I'm getting OEM this time.

I regret having the boots replaced. The originals weren't leaking, just looked cracked.

[Schming]

I see leaks on all 4 to the metal. These are the paper gaskets from mikes xs and are shot. I'm getting OEM this time.

I regret having the boots replaced. The originals weren't leaking, just looked cracked.

The boots may be fine if the vac tubes are solid, just clean them and the head and use Yama - bond no gaskets.
Just a thin layer is all that's necessary.

Also, as Mike stated if you have your carbs rebuilt the butterfly shaft seals are a good idea to replace.

[speedlimit85]

I got the carbs out and took the boots off! Parts of the gasket melted away into the rubber on all 4.

I ordered the OEM from partzilla$$--be here soon - later...

The OEM boots don't need gaskets or sealer right?

[Tonyxs11]

the OEM inlet rubbers have an O ring to seal them, but it wouldn't hurt to put a bit of sealant on if you want to.

[jetmechmarty]

Carburetor remove/install, simple.

[Schming]

the OEM inlet rubbers have an O ring to seal them, but it wouldn't hurt to put a bit of sealant on if you want to.

Yes use a thin film of Yama-bond or an equivalent sealer between the head and boots ,no gaskets.

[speedlimit85]

The barefoot aussie helped.

[speedlimit85]

I took the bracket off the top of the air filter and the parts fell out. I had to take the whole thing apart to get it right. The Aussie muscled it.

Then the throttle cable kinked and wasn't right. Then it got dark.

I should get it working good today.

[Schming]

I took the bracket off the top of the air filter and the parts fell out. I had to take the whole thing apart to get it right. The Aussie muscled it.

Then the throttle cable kinked and wasn't right. Then it got dark.

I should get it working good today.

If you would've removed your shoes you woulda' sailed through it no problem