RPM gauge jumping sometimes

[86Cutty]

The past two days; while riding my 08' Suzuki GS500F, I've noticed the RPM gauge jumping around. Sometimes it just sits at 0 for a second, then it jumps to the correct RPM's I'm at, then it just bounces around when I go over a bump or dip in the road. When I first got the bike a couple of weeks ago it didnt ever bounce around, and now it is. Does anyone know what the cause could be, or how I can fix or even just do tests to see what the possible cause is? (I'm not at all good with working on bikes, and on cars I've only changed the oil, oil filter, fuel filter, air filter, alternator, and the radiator. Which is almost basic stuff for people, so I'd say bikes are too new for me to just tinker around without any help).

Thanks for reading,
86Cutty

P.S. I almost forgot to mention that the bike wasnt loosing any power when the issue was happening. I went to other forums and posts, and the issues I found were different because there was loss of power that happened when the issue was occurring on their bikes. (I dont know if that matters any, but I just figured I'd mention that).

[-ahven-]

Is tach cable sitting correctly or is it loose? Mine tach did the same thing before it died permanently. I had metallic crap inside of the meter, it warmed up magnet there and caused wrecking of that magnet.

[ineedanap]

there isn't a cable on the 08 but there are electrical connections.  I'd start by checking the three screws on the back of the tach. (power, ground, and signal)   There really isn't much wiring to these tachs so it won't take long to rule out the connections.  

[86Cutty]

Well, I looked at the battery connection and the positive lead was loose. I tightened it up, and so far so good. I havent seen any jumping around or anything. I'll let everyone know if it's still acting up, or if it's fine after a few days. (It's supposed to rain tomorrow, so I probably wont be taking it out in the rain).

Thanks,
86Cutty

[PachmanP]

Well, I looked at the battery connection and the positive lead was loose. I tightened it up, and so far so good. I havent seen any jumping around or anything. I'll let everyone know if it's still acting up, or if it's fine after a few days. (It's supposed to rain tomorrow, so I probably wont be taking it out in the rain).

Thanks,
86Cutty

That's probably your issue.  I was reading the post thinking that sounds suspiciously familiar.  I found my battery lead loose, tightened it, and the problem went away..