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Exup & tach issues?

2K views 6 replies 3 participants last post by  Sharksawyer 
#1 ·
Ive got a 98 R1. The exup valve doesnt activate when the ignition is turned on, but it works when running? The tacho is also temperamental. Jumping from zero to inline with the revs rather than a fault code. Any ideas?
 
#6 ·
Thanks for the replys. Ive checked & lubed the cables. The exup valve moves freely. It does work but only when the engine is running. It doesn't activate when the ignition is turned on still? The tacho is weird, it doesn't show any revs at tickover. Then it usually responds when its reved, but isn't reliable. It kind of follows the engine revs, it doesn't go to say 8000 to indicate at fault? Im thinking, tps or even ecu?
 
#7 ·
The EXUP has plastic gears inside and might be hanging up on initialization. Take the cables off the motor and spin it by hand. Go around several times and feel for rough spots(broken teeth). I'd also look and see if the motor initializes without the cables installed. Remember, it will only initialize after the bike has been running. After doing the preceding, I'd then go after the TPS and then CDI. Where do you live? Anybody around you can swap parts with?

Mark

ps It's strange it works when running but will not initialize. I'd really look for a mechanical problem or maybe corroded motor connections or CDI connector.
 
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