Last weekend I fired up the Guzzi for the first time since August 10. It runs like champ! I am still fiddling with the power commander tuning and a few irritating habits it picked up while it was down. The most annoying is that the shifter doesn’t return to center on an upshift. If I tap it with my toe it will re-center and work fine, but it makes upshifts really slow. I have played with the linkage to make sure it isn;t binding. Next I will have to pull the shifter off the transmission and look inside.
The less irritating one is that the tachometer has gone crazy. First I had to reset the calibration because it was barely reading anything when I first started. Somehow the pulse to revolution had gotten set to 2.0 rather than 0.5. Then even stranger is that under certain very repeatable conditions the tach spikes. It only happens with full throttle and the engine able to rev up quickly under load. It won’t do it in neutral from idle, it won’t do it if I use the rear brake against the acceleration and just hold full throttle. I have two theories, first, I enabled the power commanders acceleration pump feature. This acts like a carburetor acceleration pump when the throttle if opened quickly. The accelerator pump wasn’t in the PC the last time I used it so since it si new, and should be responsive to the same conditions that come with the problem I am betting there. The second theory is a ground problem somewhere. Given the repeatable nature of the problem the grounding issue may be only a contributor, but grounds should’t care about throttle position.