Speedo's on the fritz, but odo works...?

My speedo is misbehaving. Tthe needle bounces around the high end of the MPH scale - but the odometer seems to be keeping accurate mileage count. I would have thought if one wasn't working, the other wouldn't be, but maybe not?

Thanks Jim. I've actually already spoke to Nisonger's, and the clock will go there next winter at worst. If I've got a working odo, I can get through the riding season here in New England and let them fix it next winter. If I don't even have an odo (as fuel gauge, maintenance tracker, etc.) I will do it sooner. Thanks - B

BrianK said:

If I don't even have an odo (as fuel gauge, maintenance tracker, etc.) I will do it sooner.

Click to expand...

The odometer and the speedometer are separate systems contained within the 'speedometer' unit. Just because one part of it fails, it doesn't necessarily mean the other one will?

How they (should) work: http://members.shaw.ca/randell/Smith/Speedo.html

Thanks Les. That's what I was hoping. Means I can put off a rebuild til after riding season. (Or more accurately, when the other bikes go up on their stands and the airhead RT comes down off its...). Cheers. - B