Topic: Speedo too fast... Waaay too fast

[gregimotis]

I replaced my Speedo cable, sheath and all, last summer and the needle began to jump around badly.  I pulled the cable off, cleaned it and the sheath and lubed it lightly with some light household oil.  Now the needle is steady but:

At forty-ish my gauge reads fifty-five and at 75-ish it reads 100mph.  I know I could just subtract and live with it, but I want things to be right.

SO, I've seen different things on old threads:

- Live with it
- Lube the cable
- Don't lube the cable
- open the gauge and clean the stuff in there (I'm a little afraid of that one)


I've tried 'lube' and 'don't lube', there aren't any significant bends in the cable routing, no irregularities I can find on the cable itself....  It seems like this should be easy. 

I'm hoping somebody can smack the back of my head and point out the obvious.

[SD750F]

Well, if it was the cable and there was friction or dragging involved, your reading would be less than actual. The typical Honda speedo uses a quasi worm gear at the axle with a fixed number of teeth per wheel revolution if I remember correctly. so I would check there to make sure there wasn't something down inside that was making the cable have one more gear tooth that was spinning the cable a little faster than normal. This is of course if your did not take apart your speedo...

Hey look on the bright side of your current situation. Now you can join Ton Up...
Scott

[gregimotis]

Thanks for the replies -

I replaced the sheath and cable and the thumbscrew at the top.  I will inspect the stuff at the bottom and see if anything looks fishy...


And actually, I can now join the ton-and-a-half up

[Geeto67]

dude, it is a 30+ year old bike...how acurate do you expect the speedo to be? They weren't acurate even when they were new. Check the speedo drive and if nothing else is wrong then live with it.

[Bodi]

Try loosening the cable attaching nut at the back of the speedo and pulling the sheath out a tiny bit. Possibly the sheath is a bit too short - or centre wire a bit too long - and the wire is pushing in on the speedo innards and making it read strange.