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Hello everyone! I am a newbie here to this forum, but am not new to motorcycles. I own several bikes and perform all maintenance on all of them. Everything from engine and transmssion rebuilds to total bike restorations. I just wanted to give you a brief history before I post my questions.
The motorcycle in question is:
1981 GS650GL VIN: JS1GP71L9C2108339 Manf. Date 12/81
My uncle, a great guy, owns a 1981 GS650L. He found it in a barn with only 8500 KM's on it. (about 5000 miles). Got it for $1.00, but it required a lot of work to get it rideable. He took it to a Suzuki dealership, had them go over it top to bottom, all cleaned inspected, all fluids changed, you name it. He spent a fair amount but he did the get it for $1.00 so it still was a great deal in the end. That was last summer. He rode the bike all last summer and parked the bike in October of 2003. He did not drain the crabs or put any sort of fuel stabilizer in the fuel tank. Periodically over the past winter he attempted to start the bike, it would not start. My uncle
did say that as the fall weather got cooler overnight, the bike did become more difficult to start.
Based on my experience with M/C's this is usually a symptom of a too lean pilot circuit. I would expect a larger pilot jet or maybe a slight opening of the pilot adjustment screw may make the bike easier to start.
Spring is close now, and still the engine would not start. The battery died
over the winter and would not hold a charge. A brand new battery was installed. Still no go.
I volunteered to help get this little bike going for him. I have no service manual as of yet and I have never owned or worked on a Suzuki before.
I get the M/C home to my shop, I did manage to get the bike started by holding the starter button, full choke, and a few rolls on the throttle all at the same time. It still was hesitant to start, the starter button had to be pressed to keep the engine going even when it was firing for a few moments to keep the inertia moving.
When I was able to keep the engine running it was running really rough. I put my hand on the exhaust pipe on the front by the exh. valves, I found only cylinders 3 & 4 were getting hot. 1 and 2 were not firing. I let the bike run this way for a few minutes and cyl's 1 & 2 never did warm up.
Next I pulled #1 spark plug and ran the engine again, lots of strong blue spark at the plug and tons of compression. I put it back together and did the same to plug #2. Same thing, great spark and compression. This led me to belive that this was a fuel delivery problem. I thought, maybe the floats are stuck closed in carbs 1 & 2. I opened the bowl drain screws on the bottom of carb 1 & 2, plenty of fuel ran out. So there is spark, and compression and fuel in the bowls...Hmmm.. I pulled the fuel tank off to get a better look at the carbs and how the fuel was delivered to the bowls.
Nothing obvious there showing a problem. Seems to me the next step is to yank the carb rack and look further at #1 & 2. Before I do this I wanted
some of your input. You people with lots of experience with these bikes offer a wealth of information.
What are some of the tricks to pulling the carbs on this bike? Remove the airbox first? Leave the throttle & choke cable connected? Are these carbs a real pain to re & re?
Any comments and help appreciated.
Keith
1982 Honda V45 Magna
1997 Honda XR650L
1983 Honda XR100
1972 Honda CT70
1976 Honda Z50a
The motorcycle in question is:
1981 GS650GL VIN: JS1GP71L9C2108339 Manf. Date 12/81
My uncle, a great guy, owns a 1981 GS650L. He found it in a barn with only 8500 KM's on it. (about 5000 miles). Got it for $1.00, but it required a lot of work to get it rideable. He took it to a Suzuki dealership, had them go over it top to bottom, all cleaned inspected, all fluids changed, you name it. He spent a fair amount but he did the get it for $1.00 so it still was a great deal in the end. That was last summer. He rode the bike all last summer and parked the bike in October of 2003. He did not drain the crabs or put any sort of fuel stabilizer in the fuel tank. Periodically over the past winter he attempted to start the bike, it would not start. My uncle
did say that as the fall weather got cooler overnight, the bike did become more difficult to start.
Based on my experience with M/C's this is usually a symptom of a too lean pilot circuit. I would expect a larger pilot jet or maybe a slight opening of the pilot adjustment screw may make the bike easier to start.
Spring is close now, and still the engine would not start. The battery died
over the winter and would not hold a charge. A brand new battery was installed. Still no go.
I volunteered to help get this little bike going for him. I have no service manual as of yet and I have never owned or worked on a Suzuki before.
I get the M/C home to my shop, I did manage to get the bike started by holding the starter button, full choke, and a few rolls on the throttle all at the same time. It still was hesitant to start, the starter button had to be pressed to keep the engine going even when it was firing for a few moments to keep the inertia moving.
When I was able to keep the engine running it was running really rough. I put my hand on the exhaust pipe on the front by the exh. valves, I found only cylinders 3 & 4 were getting hot. 1 and 2 were not firing. I let the bike run this way for a few minutes and cyl's 1 & 2 never did warm up.
Next I pulled #1 spark plug and ran the engine again, lots of strong blue spark at the plug and tons of compression. I put it back together and did the same to plug #2. Same thing, great spark and compression. This led me to belive that this was a fuel delivery problem. I thought, maybe the floats are stuck closed in carbs 1 & 2. I opened the bowl drain screws on the bottom of carb 1 & 2, plenty of fuel ran out. So there is spark, and compression and fuel in the bowls...Hmmm.. I pulled the fuel tank off to get a better look at the carbs and how the fuel was delivered to the bowls.
Nothing obvious there showing a problem. Seems to me the next step is to yank the carb rack and look further at #1 & 2. Before I do this I wanted
some of your input. You people with lots of experience with these bikes offer a wealth of information.
What are some of the tricks to pulling the carbs on this bike? Remove the airbox first? Leave the throttle & choke cable connected? Are these carbs a real pain to re & re?
Any comments and help appreciated.
Keith
1982 Honda V45 Magna
1997 Honda XR650L
1983 Honda XR100
1972 Honda CT70
1976 Honda Z50a
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