[LowLife1220]

i pulled my speedometer and cut the ring off to get a look inside to make sure nothing was stuck in there. the speedometer reads wrong and hangs up. if i just push the bike somewhere it says i'm going 30 mph. i got the gear out of the housing but i don't see anything that is obviously wrong with it. any one got any tips? theres a weighted dome that the needle and gear connect to that moves freely but was covered into black junk. does this need to be lubed?

 

[LowLife1220]

after i took it apart i asked my boss who is pretty old school if he knows what to look for in a mechanical speedometer. he said not a clue and call the speedo shop. while i was on hold i was tinkering with it and i think i already fixed the biggest problem of the needle bouncing around inacurately. i'm going to put it on the cable tonight and test it with a drill.

 

[JiMi]

I had a similar problem with the tachometer. After opening it up it appeared that the small round metal case (in which the light bulb is located) was loose from the plastic cover and magnetically stuck to the tacho mechanism. Check the first-last picture HERE. It's where I point my finger at. After glueing it back to the plastic cover, the problem was solved.

 

[MotorcycleCommuter]

I had the speedometer of my old Gold Wing apart. Basically there is a magnet the spins inside a metal drum. The magnetic attraction causes the metal drum to try and follow the magnet. A calibrated spring holds the drum back and causes the needle to point to the indicated speed. The pivot points of the drum/needle need to be lubricated and the magnet and needle must be clean and not touch.