Electrical Tach Problem

[afroese]

Hi guys,
After reading numerous posts on the subject and being unable to find my answer I am left asking a question many others have asked...what is wrong with my tach and how do i fix it?

I am riding a 2008 gs500f, so it has an electrical tach...

It started a few weeks ago when i noticed upon starting my bike it would sit at 0 for a few seconds before working. Now its not functioning correctly at all. When riding it will usually fluctuate within a range of where my RPM actually is or just be all over the place.

The first thing many will say is to check the connections. Gladly. However I have no idea what I'm looking at... I have very little experience with anything mechanical, this is my first bike and I'm fairly clueless. All i see is the connections going into the back of the tach which seems tight...(i didnt take the tach apart) and a wire running to my front wheel where the reading comes from? I've also read posts saying to check the connection to the engine or the battery. I'm pretty clueless and would rather not spend hundreds of dollars at a dealership for them to reattach a wire.... If someone could break down what i should be looking at it'd be greatly appreciated.

[numus]

http://media.photobucket.com/image/gs500f%20wiring%20diagram/adidasguy/Assorted/SCAN0004_smaller.png

That should show you the wires you are looking for.. the one that will be causing the problem is probably the Black with red strip wire... There is a connection wherever the harness connection is (in the 500e it is behind the headlight but no idea were it is on the F... should be somewhere close to the gauge cluster tho)
If you have a conductivity meter, check conductivity across that wire from the back of the tach (you will have to remove the console and unscrew/unbolt the black plastic cover to get at the actual gauge) all the way tot he ignition control unit.
On my 96' 500e I just tapped the RH ignition coil to get my tach reading but doesn't look like the 500f functions that way.

While you have the gauge apart you might want to think about going ahead and replacing your bulbs with LEDS.


Edit: Why in the hell is the cable leading off the positive battery to the fuse black?!? Dont really understand that one.

[ben2go]

Your tach should get it's signal from the CDI ignition unit,IIRC.It would help to pull the gauge cluster,unmount the tach and check the wires coming out of the back.It sounds like there maybe a bare/chaffed wire inside.You really should invest in an owners manual for your bike.They are worth the $30 or so.It can help you determin if you wanna do the work or find a shop/friend to do it.What's you location (state & city)?There maybe someone will to take a look for you.

[afroese]

Profile updated. (London. Ont) I did actually invest in an owners manual for it specifically for this issue lol. However I was rather confused by the portion (as well as many others) and it seemed to pertain to testing everything but the tach.

But thank you to both posts as i have located my issue. I removed my fairings and found the black and red wire sitting on top of my engine, the rubber protector on the connection basically burnt. The whole section seemed to be sitting very close to extreme heat so i raised it up with a zip tie. Relocating the wire alone must have corrected the issue as my tach is now functioning again....which doesn't make complete sense to me because then you'd think when it was sitting on the engine while it was just warming up it would function fine...anyways. I took it for a 15 min test run earlier and it seemed to be right on. Would it be wise to try take apart the wire and make a fresh connection or leave it be while it works?

[numus]

Profile updated. (London. Ont) I did actually invest in an owners manual for it specifically for this issue lol. However I was rather confused by the portion (as well as many others) and it seemed to pertain to testing everything but the tach.

But thank you to both posts as i have located my issue. I removed my fairings and found the black and red wire sitting on top of my engine, the rubber protector on the connection basically burnt. The whole section seemed to be sitting very close to extreme heat so i raised it up with a zip tie. Relocating the wire alone must have corrected the issue as my tach is now functioning again....which doesn't make complete sense to me because then you'd think when it was sitting on the engine while it was just warming up it would function fine...anyways. I took it for a 15 min test run earlier and it seemed to be right on. Would it be wise to try take apart the wire and make a fresh connection or leave it be while it works?

If the plastic melted off and the connect was laying on your engine block, it was grounding out the tach... I would replace the connectors and put new shrink wrap on that if that was the case.