1979 GS1000 Carb/Fuel problems

[Anonymous]

My (new to me) 1979 GS1000 is having problems. I bought it this winter and when I started it up this spring it was running fine. I drove it home from Vancouver (sea level) to Whistler (2200 ft) in BC where I live and by the time I got it home it was barely running. I could drive for a while but then it would begin to backfire on the left side and lose power, finally shutting off. I thought at first that it was the carbs and that they would need to be cleaned out but after taking them apart they seemed to be spotless. I cleaned them nonetheless and replaced the valve seals at the same time since the #1 cylinder seemed to have an abundance of oil in the head. After putting it back together it seems to be running even worse and will not keep going. Any input would be appreciated - is this related to the carb adjustment? Timing or the distributor? Perhaps the elavation because it seemed to run fine at sea level? The bike only has 37000 km on it.

[argonsagas]

I cannot see a 2200 feet altitude change making the described huge difference in performance.

Backfiring can be caused by carburetion, but you said the bike was running well, and its performance deteriorated rapidly, thus the attribution to altitude, but unless you found dirt in the fuel, the problem is likely elsewhere.

Backfiring is usually timing-related, so the first thing I would look at would be the points, and pay careful attention to the plate on which they are mounted....it may have slipped a few degrees, and affected your timing.

Recommend you check your point clearances, then check everything with a timing light.

While you are playing with the bike, if you don't already have one, install a fuel filter. They are cheap, (under CA$5..) and are worth every cent.

[SqDancerLynn1]

Sounds like you are having a problem similar to mine last year. I have 79GS850 I would be riding down the road and it would backfire and quit
It would be very hard to restart. Went thru the usuall things points, timing, plugs, re cleaned the carbs I finally replaced the coils have not had any more problems

[robinjo]

Had the same thing on my 750, loss of power and missing beats. I would first check the points too see if they are opening enough. Round cover on the right side of the engine.

[bybowtie]

pass Ill send you a Gs1100 that needs "a little work" for 700 plus freight...not in as good of overall condition but if your looking to fix one up what the hey!!!