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12,000 miles, no other mechanical issues. Bike sat for years before I acquired it, cleaned it up, etc. Cleaned the carbs. No holes in the diaphragms and they all rise and fall smoothly with applied air pressure (i.e., blowing a little compressed air into the air vents at the front/top of the carbs to make the diagrams rise, etc). Good compression. Stock headers with aftermarket 4 into 2 slash cut silencers with light baffles installed. Stock jetting both main and pilot, 137.5, 42.5.
I finally got it running ok last year. I bought a OEM air filter for it but could not get it to run right. Anything over 1/4 to 1/3 throttle ran too rich, fouled plugs, etc. I fashioned an air filter element out of light foam and was able to rev the engine even though I'm sure it did not filter the air as well. Overall I would say that the performance was mediocre. It ran weak under 4000 rpm and would often "load up" and act like it wanted to foul plugs. However, if you kept the rpms up it would cruise at highway speeds (5000rpms) just fine.
This year I took it out after letting it sit for about a month in between start ups. It got about 10 miles down the road and I figured it was warmed up enough. I gave it full throttle and tried to get it to rev above highway speed and promptly fouled plugs (yes, they were black). Got it home and disassembled the carbs; no problems, no blockages, no dirt, dried gas, etc. I reinstalled the carbs, removed the air box so I was able to watch the diaphragms rate of rise and fall. After it was warmed up and could idle on its own, I gave it full throttle to watch the diaphragms. I could be wrong but I was thinking that they did not seem to be Ising at a decent rate according to the amount of throttle and vacuum. In fact #3 seems to barely move at all. Whacking open the throttle and letting it rev to red line or just below did not seem to raise the slides more than 1/4"-3/8" (#3, maybe 1/4" at the most). It seems to me that if the slides are not opening up fully to where they should be corresponding to throttle position and rpm, THAT would account for the anemic performance, fouled plugs and overall rich condition.
The rubber elements of the diaphragms are soft and flexible. Springs appear to be fine. No visible or discernible leaks, tears or holes of any kind. There appears to be no drag between the slides and walls of the carbs....everything moves smoothly. Question: What would cause the slides/diaphragms to not rise? Would this cause the problem? Am I looking in the right place?
I finally got it running ok last year. I bought a OEM air filter for it but could not get it to run right. Anything over 1/4 to 1/3 throttle ran too rich, fouled plugs, etc. I fashioned an air filter element out of light foam and was able to rev the engine even though I'm sure it did not filter the air as well. Overall I would say that the performance was mediocre. It ran weak under 4000 rpm and would often "load up" and act like it wanted to foul plugs. However, if you kept the rpms up it would cruise at highway speeds (5000rpms) just fine.
This year I took it out after letting it sit for about a month in between start ups. It got about 10 miles down the road and I figured it was warmed up enough. I gave it full throttle and tried to get it to rev above highway speed and promptly fouled plugs (yes, they were black). Got it home and disassembled the carbs; no problems, no blockages, no dirt, dried gas, etc. I reinstalled the carbs, removed the air box so I was able to watch the diaphragms rate of rise and fall. After it was warmed up and could idle on its own, I gave it full throttle to watch the diaphragms. I could be wrong but I was thinking that they did not seem to be Ising at a decent rate according to the amount of throttle and vacuum. In fact #3 seems to barely move at all. Whacking open the throttle and letting it rev to red line or just below did not seem to raise the slides more than 1/4"-3/8" (#3, maybe 1/4" at the most). It seems to me that if the slides are not opening up fully to where they should be corresponding to throttle position and rpm, THAT would account for the anemic performance, fouled plugs and overall rich condition.
The rubber elements of the diaphragms are soft and flexible. Springs appear to be fine. No visible or discernible leaks, tears or holes of any kind. There appears to be no drag between the slides and walls of the carbs....everything moves smoothly. Question: What would cause the slides/diaphragms to not rise? Would this cause the problem? Am I looking in the right place?
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