revs down 1K?

[AZCRrider]

Has anyone run into a problem with the tach showing around 1K less than actual, but otherwise working fine? I installed the FMF and K&N air filter (no remap as of yet) and a few days after that I noticed the revs were showing almost exactly 1K less than normal. The bike runs fine, but I'd like some input before I start working on solutions. I've already taken off the front windscreen and checked all the connections.

 

[browland]

How do you know that it isn't accurate? is it possible that it is just running different due to the mods

 

[xtreme6669]

is it showing 3-600 at idle?

 

[browland]

well that's definitely a problem... The manual says you can test the tach with the digital technician so I would assume ecm spy could be used to get a general idea of the problem

 

[AZCRrider]

The bike previously idled around 1200 so when it started to idle just above 0 I realized the change.

 

[Buellysses]

Yeah, hook it up to ECM Spy, that will give you what the ECM thinks its RPM is. Sounds like you may have a bad gauge cluster.

One way to check it would be to take it to the other end of the range, see where it bounces off the rev limiter. =) (wow, that is probably the most fun troubleshooting tip I have come up with.)

I guess if you wanted the simple way, see if it goes through the full range of sweep when you first turn the bike on. Maybe the needle just moved on the shaft?

I'm not sure how the signal gets from the ECM to the Cluster, if it's an analog or pulsed-digital, either way though if you are getting noise in the signal that could goof it up. Check for loose grounds.

 

[agfish18]

did you do a TPS reset?