GS550T carb problems...help!

[gschick]

I recently purchased an '81 GS550T. When I got it the guy who sold it to me mentioned that it stalled at stop signs sometimes and he had the carbs cleaned the previous year. The bike was a great price ($540) and it looked/ran good.

Being that this is my first bike and I have very little experience with bikes in general I started learning to ride on it. It had a bit of an idle problem but not that big of a deal. I ended up dropping it very lightly after i had it about 3 days. Nothing on the outside of the bike was damaged but it never ran the same.

To start it up we'd need to pull the choke all the way out and give it gas with the throttle. The idle was really low at times, stalling it out, and then would race up to about 5k rpm and not come back down unless it was turned off even after we adjusted the idle using the knob on the carbs. Once it would get hot, if it stalled out it would refuse to start up again.

We pulled off the carbs and looked at them to see about rebuilding them or cleaning them but they were spottless. We took them to a friend of a friend who said he'd adjust them for me and after we got them back from him we put them back on the bike and now they're just pouring gas out the back of the carbs. i don't know what the guy did to them but now i have no idea what to do.

My boyfriend and i are pretty mechanically handy we just don't have alot of knowledge about bikes yet. ANY tips, advice, or knowledge would be very appreciated!!

[KitKat]

if its pouring gas, i would check the float levels.

Try basecliff's site for a manual and check the float levels, maybe your mechanic friend didn't set them correctly?

[newgsman]

if its pouring gas, i would check the float levels.

Try basecliff's site for a manual and check the float levels, maybe your mechanic friend didn't set them correctly?

not to step on toes, but i just had this problem and i think you will find gas is getting by the orings above the float. just my opinion though

[brveagle]

could be a stuck float, but most likely the float needle valve o-ring.

[mike_of_bbg]

Sounds more like a stuck float to me, or dirt on the seats. You can try rapping the float bowls with a block of wood to try to get them to seat. However, I would highly suggest fully rebuilding the carbs (including replacing all of the o-rings with new ones from cycleorings.com) according to the CV carb guild on the gsr front page. It doesn't really matter how clean they look. The guide is step-by-step; you don't need to be an experienced motorcycle mechanic. Patience, a few proper tools and parts, and some carb dip are what's required. Do it yourself and be certain it was done right. It just takes one chunk of rust or dirt in the wrong place to cause the symptoms you describe. Your sudden sideways acceleration probably dislodged something that was resting harmlessly before. Hope the time in the dip helps the seating on the needles - OEM needles and seats are rather spendy ($30+/carb).

[Danjal]

Sounds to me like he either adjusted teh floats wrong or tore an o ring adjusting them. All of which are cheap and easy fixers.

[Dave8338]

As mentioned...float settings and the o-rings on the float needles should cure the fuel pouring out the back of the carbs. What side did the bike fall on? If the left, your petcock may have been damaged.

What position is the petcock in: ON-vacuum applied only when the bike is running; PRI- no vacuum needed and fuel will continue to flow to the carbs even with the bike off; OFF should be self explanitory.

Test the petcock to see if it is working correctly. In the RUN position, there should be no fuel flowing to the carbs. You can verify if it is sealing correctly by removing the vacuum line from the #2 carb and apply a vacuum to it. If it flows when vac is added and stops when there is no vac, it won't be part of the problem that you are having.

[gschick]

Thanks for all the tips! We're gonna get new gaskets and O-rings and see how it goes. Thanks again!!

[kparkfan]

Where are the pics? We love pics

[81gs550t]

it might all be in the petcock. is it operationing properly? i've had a problem with gas pouring through down in the block. cleaning the petcock thoroughly seemed to the trick.