81 gs850g seems to die at 65?

[zedlipplin_69a]

ok i have rebuilt the carbs synced them with a manometer bike had no problem in doing that! but when the bike gets warm it starts to high idle i just let the clutch out a little and it normals out when stopped,but it seems like everytime i head out on the highway at around 65-70 it just die and starves for fuel, i have rebuilt the pitcock ,changed the air box and boots from the carbs and still the same issue any ideas would sure appreciate it thanks!!

[tkent02]

First, adjust your idle speed and mixtures with a completely warmed up engine, if it needs a little extra throttle or choke to idle cold, that's fine. If it needs a LOT of extra throttle to idle cold, there's a problem somewhere.

Clogged fuel filter, clogged petcock screen, clogged fuel tank vent, clogged screen in the needle valves, a kink in the fuel line, a crack or leak in the vacuum line, anything else that can reduce fuel flow...

Are the correct size main jets in there? Is the fuel level correct?

It could also be something clogging up the exhaust. Is the exhaust stock? If not it could be a re-jetting issue.

Good luck.

[7981GS]

Have you tried running it on Prime at HyWy speeds?

Daniel

[zedlipplin_69a]

Have you tried running it on Prime at HyWy speeds?

Daniel

yes thats is the only way it will go home is on prime after it die but sometimes it takes a while

[tkent02]

This points to a petcock problem, how much does it flow, with a hose going into a bucket when vacuum is applied to the vacuum hose? There should be a steady stream of fuel.

If it flows less on ON than it does on PRI, you need a new petcock, or at least take it apart to find out why.

[zedlipplin_69a]

First, adjust your idle speed and mixtures with a completely warmed up engine, if it needs a little extra throttle or choke to idle cold, that's fine. If it needs a LOT of extra throttle to idle cold, there's a problem somewhere.

Clogged fuel filter, clogged petcock screen, clogged fuel tank vent, clogged screen in the needle valves, a kink in the fuel line, a crack or leak in the vacuum line, anything else that can reduce fuel flow...

Are the correct size main jets in there? Is the fuel level correct?

It could also be something clogging up the exhaust. Is the exhaust stock? If not it could be a re-jetting issue.

Good luck.

okay the jets are stock so is the exaust,there is no sock on the pitcock or no fuel filter either just straight flow!what i have been concerned about is the routing of the gas lines seems suzuki wasnt thinking very clear on that the line off the pitcock bends where the line requires a sping to keep it from cremping in and the new line is bigger than the stock lines on outside diameter because suzuki dosen't make it anymore in a smaller size so maybe theres a vacum leak also thanks for the advice

[tkent02]

Try an independent Volvo or BMW dealer for good quality fuel and vacuum lines in the correct metric sizes for the old Suzukis.

[BassCliff]

Greetings and Salutations!!

Hi Mr. zedlipplin_69a,

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Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

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Thank you for your indulgence,

BassCliff

[TPL]

Interesting problem, at first I was thinking float level to low until he mentioned being able to run the bike on prime.

[7981GS]

Interesting problem, at first I was thinking float level to low until he mentioned being able to run the bike on prime.

Typical GS problem with the vacuum petcock.
At least they don't leave you stranded. Just remember to turn to run when you get off.

Daniel

[zedlipplin_69a]

thanks again guys for all this information and as everyone said it is a pitcock issue! had it checked out and there is a spot inside that when it is in the on position it pinches the o ring and blocks the flow in one of the flow holes, and i am guessing it dosent let the tank vent well at high rpm?just one little missing piece of thread inisde (pot metal) so out with the old and ordering a new one!! thanks again guys..