Thread: Speedometer not working

So I have been rebuilding my 1970 CT70H for a couple months now and am down to the last few things. I put a new speedo cable on and when you roll forward about a foot it completely maxes the speedo out? Well I was working on a bunch of other stuff at the time and was going to mess with it later, well I forgot about it and rode it and it twisted the cable until it broke. So I have a new cable but I need to figure out what’s going on so I don't break another one!

Thanks

You have to be certain that both ends of the cable are properly indexed. I've seen them installed out-of-phase and the results have ranged from a temporarily non-functioning speedo to speedo mechanicals being broken inside the housing. Unfortunately, it sounds like yours may be in the latter category. If it is, the speedo is (rude word rhyming with "duct") ready for replacement.

Please don't take this as alarmist, as that's not my intent. Just prepare yourself for the worst & hope for the best. Meanwhile, pull the speedo from the headlight bucket, install the new cable, being sure to seat the square drive properly and try spinning it slowly by hand. If the speedo action seems normal, then try spinning it slowly using a variable speed drill. Set the drill for "reverse" rotation. If the speedo works normally, then you're in luck. If not, start scanning ebay. HTH