I bought a 82 Interstate in Dec. that run and sounded pretty good for being stored for a while. So I went to restoreing it before riding it. Rebuilt rear shocks, front forks, front & rear brake calipers and pads, had seat redone, timing belts, checked valve adj., removed and cleaned carbs., new tires, and alot of TLC. Looks and sounds great. Yesterday the weather was right, out I go to find out it way down on power. When you roll on the throttle it seems to spark knock I think. I rechecked timing GOOD. compression test GOOD. synced carbs GOOD. The only thing I'm not sure is vaccum advance? I unplugged it from the carb, not much vaccum and running didn't change. Can someone help me with how much vaccum it should have or how to check it?
1100s do not have slide diaphragms.
The vacuum advance doesn't do much and is hardly noticeable if disconnected. Be sure on the cam timing (cam timing does not effect ignition timing) and be sure it is firing on all cylinders.
I think he means its not a replaceable rubber slide diaghram like the 1500's have, 1100's have aluminum cv slides, the knocking sound u mentioned usually means carbs arent synched correctly causing the engine to run unbalanced, check to make sure the linkage is all working smooth, those multicarbs can be a nightmare to get right. as far as the vacuum advance goes check it with a manual break bleeder/vacuum pump should hold about 3 pounds vacuum, the accelerator pump on the carbs can affect acceleration also.
What exhaust system are you running? If you're running a standard system then you're looking in all the right places, but if you're not that could be your problem, I lost a whole bunch of power when I ran a Dennis Kirk setup on mine years ago, got it all back when I went back to standard.