bike running bad HELP

[NelanCustoms]

might be the carbs or shims?

when i am riding the bike when i let off the throttle then get back on it there is no throttle power and it randomly back fires. any thought what might be my problem? thanks 8-[

[bwringer]

Intake air leak - carb boots/o-rings, carb/airbox boots, unsealed airbox.

[NelanCustoms]

air box panel on the left side doesnt seal perfect because that rubber gasket isnt in great shape. could that be it? looks like its sealed good. can i buy a new gasket for the airbox panel? if so where?

[Mr. Brown]

First off, if the red bike in your post is yours, I'd be willing to bet there's an air leak somewhere...

I went to Wal-Mart and got some black gasket tape. One package was enough for both covers. Works great! Be sure not to leave any gaps.

[rphillips]

Has the bike just started this? Did it start all at once, or gradually? Had you just done any maintenance or adjustments? Could be air box gasket, but not likely unless you just had the lid off & replaced it when it started. Couldn't be sure what the problem is, but carbs would be a good possibility. I learned from this forum, "SEA FOAM". About $6.00 at Wal- Mart or AutoZone. Won't fix major problems, but for the money, it's worth a shot

[NelanCustoms]

the airbox gasket looks a little to big. right shape though. maybe it has been stretched alot. also has some bad cracks and tears in it. do local dealers carry them or can they order the gaskets? i bought the bike recently and it came with the problems

[TheCafeKid]

Fix the airbox.. May be able to find a gasket at bikebandit.com, Z1Enterprises.com, or various other places...if that doesnt work, then yeah...valve adjustment (i'd do it anyway if i were you) if you've any suspicion that the intake gaskets are worn, change em, then if that STILL doesnt fix it, look to the carbs...OR...you can do like i did and chase your tail in circles untill you do it right..

[NelanCustoms]

i bought the bike from some kid that said when he bought the bike they guy gave him a box if shims, the kid gave me the shims too. might be that? lol

[marvinsc]

Weatherstrip material works Great. I don't think the OEM Gaskets are available. This is a Rite of passage for almost all 850 Owners but other GS models are succeptable as well.

[NelanCustoms]

so what should i use? weatherstripping? gasket tape from walmart? whats that stuff called exactly

[NelanCustoms]

bikebandit.com has the covers but doesnt list the gasket. does the covers come with the gasket? i will call them tomorrow and find out if no one knows

[rphillips]

I learned from an old mechanic friend that died in 1984. If you don't know what the problem is, start with the cheapest easiest things first. Seems the 850 owners have been there before, sealing the airbox good would be a good cheap easy idea. It's hard for me to understand, as I've mainly owned GS 1000's & 1100's, and I've always rejetted & removed the airbox lid on every one of them. I couldn't imagine worrying about one leaking a little. But I've never owned an 850.

[bwringer]

The airbox gaskets are not available. Seal the airbox side covers using self-stick weatherstripping. This is very simple and cheap.

You also need to make sure the rim of the top of the air filter is sealed, that there's a good foam element in place on the air filter, and that the element is VERY lightly oiled.

Don't bother calling BikeBandit with an actual question -- it only annoys them and wastes your time.

While you're thinking about it, check the valve clearances. Get a manual http://repairmanuals.com , or poke around the forum for BassCliff's instructions.

The next step is to replace or check the rubber boots between the airbox and carbs (do this anyway even if you think they look OK). You most likely also need the rubber boots between the carbs and the engine, and you defnitely need the o-rings under these boots as well.

Instructions for the intake boots/o-rings:

http://bwringer.com/gs/intakeorings.html

Unless all the above is PERFECT, the bike will not run right. Every GS850 owner has needed to take the above steps. There are no workarounds, and cracked or otherwise nasty intake boots cannot be repaired.

You might as well set aside a few bucks and order a new petcock, too. These also need to be replaced every 20 years, so yours is overdue if it hasn't already been replaced.

Get it right, and an 850 is pure magic... \\/

[NelanCustoms]

if i eliminate the air box where can i buy the jet kit?

I learned from an old mechanic friend that died in 1984. If you don't know what the problem is, start with the cheapest easiest things first. Seems the 850 owners have been there before, sealing the airbox good would be a good cheap easy idea. It's hard for me to understand, as I've mainly owned GS 1000's & 1100's, and I've always rejetted & removed the airbox lid on every one of them. I couldn't imagine worrying about one leaking a little. But I've never owned an 850.

[NelanCustoms]

inside my air box is thick oily dirt. is this a bad thing? when it says clean air filter in solvent, what should i use? parts cleaner? its a UNI filter