I've got a 1999 R1 with a 2001 R1 motor in it. The bike has aftermarket exhaust, aftermarket airbox, and aftermarket coils. My problem is my tachometer. The tach needle will work momentarily and then jump to 7200 rpm and then back down to 0 -- even if the bike is still running. I think this is some kind of trouble code. The bike runs fine, but it will continue to pop up this trouble code about every 6 seconds, so I can't use my tach. I've tried changing the wiring harness and gauges over to 2001 parts, but that still didn't fix it. Can anyone tell me what could fix this?