Ahem.. I have a wee problem...
I had my BSA out to a show in November. She was trailered there and back & only ridden the short distance from the trailer to her stand, which was about 50 yards or so.
Prior to loading the bike outbound to the show, the speedo was working fine.
I never checked the speedo upon return to base, but a couple of days ago I was faffing about with her when I noticed the speedo was stuck at 15mph!!
I've not taken her out for a run since discovering this glytch, but I have removed the speedo and given it a gentle tap to see if that will return it to zero.. It didn't :-(
I've also oiled the cable thoroughly and greased everything that I can grease - everything turns freely.
....Doesn't sound good; nothing much more can be determined until the clockwork is removed from the case...sorry, most likely there is no easy out.
If it's an original WD speedo, it may still be sealed with an aluminium rivet that prevents the bezel from being unscrewed. If it's been apart previously, you may be able to remove the bezel and the screws on the back of the case which will allow the entire mechanism to be removed.
Once apart, you should be able to see what the problem may be. For most of us, at this point it's time to find a specialist in chronometric instrument repair!! Chrono speedos of any sort are becoming hard to come by, parts are difficult to find, and they are expensive to buy or repair.
Hello there, I used "Chronometric Specialist Services"they're based in Nottingham. When I contacted them about my WM20 speedo, they still had N.O.S.boxed items as well as, overhauled units and of course will take your speedo for repair.
I'm told you have to be vary sparing with any lubrication when it comes to speedo's, my speedo didn't work so just before christmas I sent it to Phil Woods in Littlehampton, he is on the net, phoned me a couple of days ago to say the thing was all working and it only really needed a clean of all the accumulated gunk/oil! £70 I can live with this.
Try turning the drive on the speedo to release the ratchet it won't zero otherwise. The square end of a 4BA tap fits well. If that works check the cable and drive. If needle doesn't zero then a strip down is needed.
