My tach will not operate smoothly.  WTF?!  I don't really know what the problem is?  I checked the 2 connections and they are firmly connected.  Could my cable be going bad?  As the RPM's rise it just kinda bounces around towards the actual RPM's.  It's really lame and I want to fix it.

Bounces as in "faltering signal" or bounces like the needle is loose?  A faltering signal will result in very crisp movements.  A broken tach with wobble and never really settle anywhere except zero.  Good test is to start the bike on on a level surface, chock it to sit around 3000rpm, and knock on the cluster with your knuckles.  If it wobbles around then the tach likely needs replaced (very very rare).

Only thing you can do in either case is super double check all your wiring.  You could also trying running a seperate signal feed from the coil to the tach.

Out of curiosity, you did check that your battery was charged propperly, right?

It could be the cable or it could be the connection points...  The ends have a little D shaped end...  If that it warn (or the other end it warn) it'll bounce...

But, it could also be the guage itself...  In my F.O.R.D. my Speedo bounces, sticks, and randomly flips out.

not any wiring to check really.  it's a 91 so it's all cable driven.  I have a spare tach im going to plug in when I get home to see if it does the same thing.  I just wanted to see if anyone has had this problem before.  It sounds more like a broken tach because it does not settle anywhere usually.  At say 5000 rpms it will float back and forth a few hundred RPM's.  Im thinking it's the tach.  also found out why it wouldn't illuminate.  Both bulbs were burnt.  As soon as the LED bubs i ordered get here we'll be in business.

yeah cable drive tachs do fail a little more offten.  Make sure that the cable is spinning freely, though.  Pull it off, fill a small plastic bag with penetrating oil, stick one end of your cable in it and duct tape the bag closed really well.  Hang it upside down and let it soak through.  I've seen bad cables more often than tachs.

Yep, sounds like the cable needs some lube.

After Slowe30's repairs, his tach bounced. We checked both ends of the connection...just fine. I pulled on the cable at one end (can't remember which), and the thing pulled out completely. The cable broke and had stringy bits catching just enough to make the needle move.

Disconnect the cable at both ends and pull on one OR grab both linkage ends and turn in opposite directions. It shouldn't budge if whole.

Quote from: starwalt on January 19, 2006, 06:43:53 PM
After Slowe30's repairs, his tach bounced. We checked both ends of the connection...just fine. I pulled on the cable at one end (can't remember which), and the thing pulled out completely. The cable broke and had stringy bits catching just enough to make the needle move.

Disconnect the cable at both ends and pull on one OR grab both linkage ends and turn in opposite directions. It shouldn't budge if whole.

good advice, I will do that as soon as I GTFO of work.  I also got some temporary bulbs for the gauges to last me until my ebay ones het here.  They are LED's that change 5 different colors on their own when powered.

the 04's and up might be electric tachs, but the earlyer 500's are all Cable drive from factory,  they all get cacked up and need a good cleaning.  once a year ill pull mine comepletely out remove the flex cable and give it a good rinse out with brake cleaner, pour alittle engine oil or slide some wheel bearing grease on the flex cable before putting it back in the housing and reconnecting. seems to work well enough for the speedo too

they sell cable maintanence kits at cyclegear.  I may just go get me one of those tomorrow and see if tht fixes it.  I have a spare cable that im gonna swap onto it tonight just to see if thats the issue or not.

http://www.houston-imports.com/users/that_guy/bike/gauges.AVI

I squirted probably an ounce of WD-40 total into the tach cable and also changed the tach lol for the other one i have and it works fine now.

It's most definatly the cable. Just lube it and check the connections. I had an old toyota that did the same thing.

Regards,
JG

Yup probably the cable needs some lube. If you spun around as many times a year as the tach cable does you would need to be lubed too.