Posted by Johnd [172.69.70.104] on Sunday, September 16, 2018 at 08:14:39 :
In Reply to: Re: Speedometer question posted by Milo in Pa [172.69.62.175] on Saturday, September 15, 2018 at 20:51:10 :
If you are seeing a 20% error in speed, that would seem that the tires would need to be off 20% in circumference (not diameter).
A 30” diameter tire versus a 32” diameter only makes a difference of 6” of travel per one revolution of the tire. Thats nowhere close to a 20% error. I would look elsewhere for the problem.
I once had a speedometer cable that was worn on the ends where they are squared off to fit into the socket in the speedometer input. It was slipping in the socket!
If the cable seems OK, I would focus on the speedo itself for the problem