@ a loss

[martinfink]

just got a 81 gs850g and thought it had a carb prob so as soon as I got it home pulled carbs and cleaned .No differance.Started with air screw 2 1/2 turns would not run only with carbs wide open and it only stumbls another turn out on the top screw and the same stumble .still only wide open and yes put new orings between carb rubbers and head.cleaned ground and checked spark .It has spark but don't know how to tell if it is strong.would think if it was the coils it would just not run at all.plugs are black sootish .any help Thanks martin:-?

[seuadr]

black and dry plugs means too rich, black and wet plugs means an oil problem. sounds like you have black and dry, which means lean it out a little. you may have gone too rich when you were ajusting.. but then if you are running it full choke, that could be the problem too. these bikes are pretty cold blooded, am i wrong in assuming you let it run for like 5 mins choked and then made sure it wouldn't run without?

[greg78gs750]

how are those valve clearances?

[martinfink]

It did not run for 20 sec at a time.and the head gasket was replaced from what I was told.the compresson is not grate but not under 100lbs.

[martinfink]

the plugs are sooty and dry. rich how do you lean it out?

[heathen]

you can lower the needls in the carbs to lean it out. just drop it one notch at a time.

[JayH]

How did the filter look? Try to run it w/o the filter if it is too dirty. If that doesn't lean it out you might want to clean the carbs again.

[seuadr]

how are those valve clearances?

gonna have to second greg here, valves are oft overlooked ( like when i posted! :-))

[flatblack850L]

I've spent many many hours screwing with the fuel on my 850L. I don't quite follow the problem. Is it??

A. Poor idle - runs rich

B. Poor running Midrange, but does idle

Also a note: it is real easy to mess the cam timing up when doing heads on these bikes, i did that too, maybe cam timing is messed up?

Love to help,
J

[chef1366]

Before worring about carbs what is the condition of the engine? Compression numbers? Valve clearance? Airbox installed? Battery any good?

[TheCafeKid]

Valves...valves?? VALVVVEES. Oh yeah, did we mention adjusting the valves? You're gonna end up just chasing your tail till you're pi$sed off and sell the bike if you keep futzin with stuff without assuring the valves are adjusted in spec. Has MASSIVE amount to do with how the bike will run at ALL ranges, cold, hot, idle WOT whatever...

[martinfink]

So got it running but only with the fuel shut off so my thought is as the bowls drain it leans and starts runs realy ok until it runs out of gas and I put to pri .so are the floats not right they are about 7/8 off the bowl rim" as close as I could.???

[Steve]

The floats don't get measured from the rim, they get measured from the gasket mating surface. Also be sure to measure to the correct part of the float. Measure to the lower part of the 'step', which is the top part of the circle.

Now, back to square one ... have you bothered to check the valves yet?
If the engine is not breathing correctly, it won't matter how much gas you put in there.

.

[martinfink]

Thanks Steve and no on the valves but your persistence is taken .will check them to day but with out shims I would be S O O L.but think that I am closing in on the prob thanks .

[Steve]

You can check them without changing anything. There is a slim chance they might be OK, but you will never know until you check.

Now for a shameless plug ... send me an e-mail, I will send you a copy of my Excel spreadsheet that will help you figure out what shims you need. It also helps you keep track of your shims from one adjustment interval to the next.

.