Bucking prob gs 1100E 1980

[Anonymous]

Ok, i own a 1980 GS1100E

Considering: the bike didin't run for 12 month, in the beginning of last year the distributor, magneto, starter were rebuilt\done, i got dyna coil and K&N drop in and got 26000km on the clock.

My problem: I took the bike for my first ride yesterday, run well, good start but around 4000-5000, if sustained for around 30 sec, there is "misfire", the bike slow down and catch up, slow down and catch up, i was doing lambada! I also heard 2 back fire. Later i was able to go to 6000rpm before she did it. I experienced this prob 7 times in my 30km ride.

My question: Do my carb are clug by the 12 month stop and need to be ride to be cleaned?
Or considering that there is back fire, i got a fire porblem (spark plug for exemple)?

Thank for your time guys, i f you need more info no prob.

FREU

[Billy Ricks]

Time for a thorough carb cleaning.

[TheBigRed]

Also..

check your petcock. I had something simular happen when the diaphram in the petcock became punctured and started sucking gas down the vacume tube.

(of course the bucking wasn't quite as noticable on a 550 as it probably would be on your 1100)

Amos

[Anonymous]

Thanks for the answer, but what is a petcock????? Whats the fonction of this part and where it is??


Thanks

FREU

[lhanscom]

It's the valve on the gas tank that the hoses connect to.

[Anonymous]

Super, thanks, i'll check this out.
Whats a good way to clean the petcock?
Deconnect it and clean it with a carburetor cleaner?

Thanks again all

[KrazyKarl02]

I think it is the carbs

I have also had this problem, you can check the vacuum hose to the petcock, but my money is on the carbs, sounds like the main jet's fuel air tube thingy (the crossed drilled thing) I used to know what this was called! I had the same problem on a 1000 one time.

[Anonymous]

Super, thanks, i'll check this out.
Whats a good way to clean the petcock?
Deconnect it and clean it with a carburetor cleaner?

Thanks again all

Watch out. The carb cleaner will do nasty things to the plastic and rubber, even some metals (which, btw are not in the petcock).

So take the gaskets out first.

Michael

[Anonymous]

I had exactly the same problem and it turned out to be my petcock. go on ebay and you can get a rebuild kit for about 16 bucks.

[Dink]

Re: I think it is the carbs

I have also had this problem, you can check the vacuum hose to the petcock, but my money is on the carbs, sounds like the main jet's fuel air tube thingy (the crossed drilled thing) I used to know what this was called! I had the same problem on a 1000 one time.

It is called the Emulsion tube, IO had a similar problem when I first purchased my 1150, it turned out all four emulsion tubes were blocked solid in the holes that are in the side, the mechanic sat there with jet drills cleaning them out , and I have never had the problem since, If you let the bike sit for twelve months the carbs are absolutely begging for a thorough clean out and balancing.
Dink

[Motorcyclemodeller]

Don't rule out a kinked fuel line or plugged fuel filter, improper float heights could also be a factor. It sounds like a starving fuel condition to me, fuel petcock and vaccuum hookup, even a plugged fuel tank breather hose. I would check these prior to pulling the carbs and checking the emulsion tubes.

Hope this helps,

Dr. Dre

[Dave_A]

Don't rule out a kinked fuel line or plugged fuel filter, improper float heights could also be a factor. It sounds like a starving fuel condition to me, fuel petcock and vaccuum hookup, even a plugged fuel tank breather hose. I would check these prior to pulling the carbs and checking the emulsion tubes.

Hope this helps,

Dr. Dre

Try running on PRIME...

if it runs good on prime -> petcock problem...

Just remember to turn off prime when you're done...

[snowbeard]

second on the prime, might be a lack of fuel getting to the engine, I would have this problem when running high for more than a minute or two, except without the surging, it would just kinda die out to idle or low rev, but if I let up for a few seconds, then I could crank it back up till it lost flow again... found out I needed to keep the tank pretty much topped off or there wasn't enough pressure to flow thru the rust filled filter

carbs dirty also sounds possible, but sometimes they'll work thru it as it runs, if it runs!

[Anonymous]

Sounds like everyone is right on the money. Do the easy things first. Try a fresh tank of gas.