I am working on a friends 82 GL500 silverwing.  It is in OK shape, he maintains it well so mechanically it runs like a new bike.  But his speedometer stopped working a month ago.  He said he heard a buzzing sound then it stopped working while riding.  I noticed the speedo cable was not turning at all -which told me the issue must be in the speedo drive (an assumption).  I ordered a used speedo drive and cable for cheap enough money.  I installed it and the speedometer makes an awful racket (like the rattle/buzz a really lose bearing might make on a shaft) and bounces a little, but does not work.

Not being overly familiar with older bikes I want your thoughts on these things if you could share...

- (drive and cable replaced) with the cable disconnected from the speedo, the cable spins now, but pauses randomly for a brief second at low speeds (as fast as I can spin the front wheel).  I can also grab the end of the speedo cable and stop it from spinning easily with my fingers.  Is this normal behavior?

- Assuming the replacement parts are good (and appear to be), should the speedo make any strange sounds at low speeds?

- is there ANYTHING else that could cause a problem other than a bad speedometer?  Are there any more parts or things to check at the wheel end?

I hate to barge in and just ask such questions, but my friend is not wealthy and uses his GL as a daily commuter. If I can save him a few hundred in repair costs it helps him a lot.  Any advice are questions for me would be appreciated.

Thank you for your time!

Since the speedometer has 2 parts: odometer and speedometer, are both failing?

Connect the speedo cable to a variable speed drill. Check it that way. It will rule out or confirm the gear box on the axle.

With the drill, and just the cable, does the end connected to the speedo turn? Though you can manually check for a broken inner cable, drill are fun to play with.

Do you have any other speedo? If fitting is the same, connect it with the drill and see if it works. If it does, it confirms you're testing it correctly.

Could the axle gear box be turning the cable the wrong way? With a drill, try slowly in both directions. These are OK for reverse as that's what happens when you go backwards. They're also designed not to work in reverse so you can't run the odometer backwards.

I see you mention the cable is flaky without the speedo connected. It is possible the cable is pulling out. That is, without the speedo to keep the inner part pushed in, it can slip out of the lower end. Probably you see you can pull the inside out if you try. Try pushing it in as you fiddle with it. It is possible the axke gear is worn.

The drill test can confirm speedo or gear box.

Remember the cable can pull out and not mate at the other end. We experienced that yesterday with a tach cable. We did have to push it in and fiddle to insure it was mating wirth the thingy on the engine head. Then the cable spun. Tach was sluggish, but swapping tach it was good. So cable OK but tach sluggish probably due to sitting for years.

I can do the drill test with the speedo.  It does make an awful racket, but a drill test will confirm for sure.  Will do and report back tomorrow.

here is the cereal box condensed version of how the speedos work on those old hondas. sounds like it has given up the ghost. on thing they do not mention is this link is that the needle movement is dampened by a silicone liquid. with age and use once it drys up all bets are off. but for an 82 goldwing he should be able to find one on ebay.



http://www.ehow.com/how-does_5033375_motorcycle-speedometer-work.html

John, I have an old Honda speedo you guys can have for the cost of shipping. Not saying it would work or look original, but it's something. .....

The new speedometer drive functions properly off the bike and looks really clean and sharp. The old one is worn more but still works too.
The cable is inserted properly and lubed.
The speedometer does not register anything when I put a drill on it -makes a raspy sound intermittently.

OK so...When I install the speedo drive and line up the tabs (by inserting the ring gear making sure the tabs are aligned then sliding the drive housing over the ring gear), then carefully tighten the shaft making sure the drive does not move, the drive intermittently spins, but can be stopped with little effort. I tried both the new and old speedo drive. The old does not move at all, the new occasionally turns but will just stop -if I spin the wheel backwards it will bite and start to turn, but going forward again it will turn then stop again (the metal tab where the speedo cable goes).

I am starting to wonder if the tabs in the wheel are worn down to where they no longer make enough contact. I am really wondering if the speedo locked up, as did the speedo drive, and the wear was sufficient to cause it to slip.

At this point I have no reference to see if the tabs in the wheel are worn, but I can't see anything else that I can do other than suggest replacing the wheel unless that part can be replaced. The online manual does not seem to indicate it is a replaceable item.

Please give me feedback...even if you just want to say I am an idiot for missing something. Would love to hear your thoughts