So occasionally, when my bike is hot, after the tach needle passes 7k, it starts bouncing around like crazy. It doesn't happen when it's cold, and doesn't even always happen when its hot. I was in the middle of a 200 mile ride when it started happening the first time, last monday, and I didn't even notice till I hit a construction zone on south I-25 and had to slow down, looked at my tach when I was engine braking and was like, "...wtf?"

Anyway, the tach on a 07 is electronic right? And what could be causing this? The sending unit on the engine? I can't imagine it being the tach itself. I don't have any other issues with the bike, aside from having to switch to PRI on the interstate to avoid bogging down every 20 minutes . Just rolled over 8k miles.

Hi,on the F models bouncing tach seems to be first indicater of a bad earth/loose battery connection.

Nothing to worry about. In the headlight bucket check the tach cables or unplug - plug all of them  (I don't have the manual with me right now to tell you which color cable you have to check).

Thanks, I'll check the cables and the battery, I haven't checked the fluid in a while either, guess it's time.

I had a similar issue and the tach was replaced under warrenty on my '08 (bought last summer).  It would get up to 5500 then wiggle and then at 8500 it would stick and jump up about a thousand.  The shop determined it was a bad tach.  Checking connections is a lot cheaper (and easier) than dealing with the stealership though

So I checked everything, all the connections are tight. I don't really know what it could be, any other ideas? I doubt it's the tach itself since its fine until the bike gets hot.

Quote from: tykho on July 25, 2010, 11:16:04 AMI haven't checked the fluid in a while either

Maybe your tach fluid needs to be changed.

Yea I meant I needed to add water to the battery

Could it be the tach itself? I didn't think that would be a likely culprit since it only happens when the bike heats up, but I really can't think of anything else to check. I'm thinking about just taking it into a shop at this point, it's just very annoying.

I had a similar experience on a car.  after sitting in the sun all day, the tach would get stuck, and not come back below 2000 rpms till night. in my case, it was the back, where the numbers where at warping with the heat,  then the tach needle would hit it, and get stuck