Many people know that it is a well known common fault that rev counters go crazy on the 32,33 and maybe 34 models. The fix is easy. Just follow the guides that instruct you to resolder the motor at the back of the Rev counter. If you do this and then notice that the Rev counter is inaccurate, you can pop it out and adjust it. See pic attached if you turn the adjuster 1/2 a turn is approx 500rpm. Counter clockwise will raise the Rev counter needle up.