clofan
04-18-2016, 12:42 PM
Having some issues with the GZ lately. I've developed a small-ish oil leak, I think it's coming from the valve cover as oil is visible on the very top fin. I had a leak at the acorn nut near the spark plug, but it went away (or at least greatly reduced) when I re-torqued the nut.
Next, it will start and idle/run, and do so OK. After maybe 30 seconds to one minute of idling, it will miss one revolution and bog down, stopping the engine a few seconds later. Interestingly, in some brief (but by no means comprehensive) testing I found I could replicate this by leaning the bike on it's kickstand. It would seem to idle longer if it is straight up, but as soon as I lean it on the kickstand it will miss, bog, and die. It will still miss/bog/die if it's straight up too, but I wonder why leaning it forces the issue. After it dies, it is harder to restart-- I have to give it a decent amount of throttle and it blows soot out the tailpipe after a few hard revolutions.
I have also been finding gas in my airbox after running. This has lead to an overly rich mixture, with visible smoke/soot out the tailpipe when running. I think this may be the cause of the miss/bog/die from the previous paragraph. I have been in the carb and the floats are good, the only modification is the needle shim mod which I plan to undo. While I have the carb out, I will drill the factory mixture cover so that I may have access to it.
Any thoughts on this? I plan to change the oil and filter (1500mi since last change), check timing, replace spark plug, undo needle shim mod and recheck floats. I just replaced the air filter yesterday, with no change in condition. I will eventually replace the valve cover gasket and maybe the upper head gasket too, but I realize that requires removing the engine from the bike so will need to dedicate a weekend with a buddy to help me with that. I think I can still ride with the oil leak until then, as long as I keep an eye on the level.
Next, it will start and idle/run, and do so OK. After maybe 30 seconds to one minute of idling, it will miss one revolution and bog down, stopping the engine a few seconds later. Interestingly, in some brief (but by no means comprehensive) testing I found I could replicate this by leaning the bike on it's kickstand. It would seem to idle longer if it is straight up, but as soon as I lean it on the kickstand it will miss, bog, and die. It will still miss/bog/die if it's straight up too, but I wonder why leaning it forces the issue. After it dies, it is harder to restart-- I have to give it a decent amount of throttle and it blows soot out the tailpipe after a few hard revolutions.
I have also been finding gas in my airbox after running. This has lead to an overly rich mixture, with visible smoke/soot out the tailpipe when running. I think this may be the cause of the miss/bog/die from the previous paragraph. I have been in the carb and the floats are good, the only modification is the needle shim mod which I plan to undo. While I have the carb out, I will drill the factory mixture cover so that I may have access to it.
Any thoughts on this? I plan to change the oil and filter (1500mi since last change), check timing, replace spark plug, undo needle shim mod and recheck floats. I just replaced the air filter yesterday, with no change in condition. I will eventually replace the valve cover gasket and maybe the upper head gasket too, but I realize that requires removing the engine from the bike so will need to dedicate a weekend with a buddy to help me with that. I think I can still ride with the oil leak until then, as long as I keep an eye on the level.