Bikes dies after few miles at highway speeds...

[BentRod]

sounds like petcock, or more specifically the diaphram in it. it probably has a small leak that is not significant at lower speeds and lower loads on the engine.

Happened to a friend's petcock. prime did not work, and the engine bogged out at highway speeds, gobbling up fuel.
eventually his pilot circuit plugged on one carb and fuel was coming down the vacume line.

 

[jadesystem]

I like George Fix, as he is the GS brother's friend indeed. He is cheaper,
faster, better support, and quick shipment turnaround to your door than Bike Bandit, and/or Flat-Out Motorcycles.

I like him and his professional all-around parts services. His replies and
response time to service your needs are lightning quick. And George is
also very reasonable, and he is easy to talk to.

:-D\\/

 

[Gixxer Dan]

Already guys, if you guys say go with george fix, i'll give it a shot for the new petcock. any links to his auctions or ebay store?

 

[Gixxer Dan]

alright, I've been really contemplating this...

how bout if I use an adapter plate (50mm right?) with a 3/8 petcock from pingel like this: http://www.z1enterprises.com/detail.aspx?ID=2718

Then attach a 3/8 outlet petcock like this: http://www.z1enterprises.com/detail.aspx?ID=1744

I understand it would not be vacuum activated and lack the built in safety mechanism of the vacuum, but I think I can manage shutting it off after each ride.

do you think it would work if I plug the vacuum vent on the carb and go with this setup?

 

[Guest]

alright, I've been really contemplating this...

how bout if I use an adapter plate (50mm right?) with a 3/8 petcock from pingel like this: http://www.z1enterprises.com/detail.aspx?ID=2718

Then attach a 3/8 outlet petcock like this: http://www.z1enterprises.com/detail.aspx?ID=1744

I understand it would not be vacuum activated and lack the built in safety mechanism of the vacuum, but I think I can manage shutting it off after each ride.

do you think it would work if I plug the vacuum vent on the carb and go with this setup?

If you want to spend the money that's the way to go.
Plugging #2 won't hurt anything.

 

[m0ng00se]

Same issue here

Same issue here

Yeah, I just picked up my first GS850. It is a 79. I had to drive on the highway to get it home. IT seemed to do fine at lower RPM but once I went above 50 MPH it would go for about 5 miles then sputter and die. IT was not a fun drive home. I am just wondering if this could be related?

m0ng00se

 

[Gixxer Dan]

Yup, that sounds about the same symptoms I'm having with my GS550. I went ahead an ordered a manual petcock from Z1 and hope that cures my problems. I'll keep everyone updated as soon as I swap out petcocks and test run it.

 

[Gixxer Dan]

Well, my manual petcock and adapter plate came in from Z1 today and I wasted no time ripping the old one off and installing the new one. After I let the gasket dry, I refilled the tank with gas and took her out for a freeway test run for the moment of truth....

low and behold the old horse pulled hard in all 6 gears and held a constant 7K RPM in 6th gear for over 5 miles. I actually had her over 90MPH for the first time!!! Not that I condone this type of riding, but it was 3AM with no traffic on the 210 FWY and it was done in the name of GS Science \\/

So that was it, swapped to a manual petcock, plugged the vacuum from the carbs and thats all she wrote.

 

[Guest]

Well, my manual petcock and adapter plate came in from Z1 today and I wasted no time ripping the old one off and installing the new one. After I let the gasket dry, I refilled the tank with gas and took her out for a freeway test run for the moment of truth....

low and behold the old horse pulled hard in all 6 gears and held a constant 7K RPM in 6th gear for over 5 miles. I actually had her over 90MPH for the first time!!! Not that I condone this type of riding, but it was 3AM with no traffic on the 210 FWY and it was done in the name of GS Science \\/

So that was it, swapped to a manual petcock, plugged the vacuum from the carbs and thats all she wrote.

I was on the 210 a couple of months ago and was lucky to go 2 MPH. I could of walked to Bakersfield and got there faster. :|

 

[Gixxer Dan]

I was on the 210 a couple of months ago and was lucky to go 2 MPH. I could of walked to Bakersfield and got there faster. :|

Definitely familiar with that side of the 210 during rush hour. Luckily I know work 10 miles away, but the 15 fwy is a whole nother monster...