I have a 89 Indy 400 that has a bog and won't rev past 5000 rpm even with the track off the ground. I have tried cleaning the carbs, changing the jetting, new plugs, new gas, exhaust isn't plugged, pistons look good and has 115-118 psi of compression. Also the crank seals and carb boots are good. I have been trying to get it to run right for the last four days and nothing seems to be working. tonight for some reason it reved right out to 9000 rpm and ran perfectly with lots of power and I didn't change anything:confused: what do you guys think this could be some type of electrical issue?
CDI? Timing?