1998 Road King with inaccurate Speedometer

[Deltamaster]

Hi.
I have a 1998 Road King and the speedometer started reading inaccurately some years ago.
The speedometer reads about 15 to 20 miles per hour slower than actual cruising speed.
I suspected the speed sensor on the transmission and replaced it. This provided no joy.
The Speedometer had the typical bleeding on the Odometer display and seemed a bit crusty on the connections so I decided to replace the speedo head. I found an OEM NOS brand new speedo and replaced it. No Joy.

One thing I noticed was that when I purchased the bike, when I turned on the ignition the speedo needle would swing across the dial and back as the ignition activated. This no longer occurs.

I would think replacing both the speedo and the sensor would have solved the problem but it has not..
Does anyone have any ideas as to why the speedometer does not register properly?

 

[tourbox]

Welcome from So. Texas. I would of thought both changes would of fixed the problem also. Perhaps someone has changed the gearing in the tranny. I don't know which gear pulses the sensor.
tourbox

 

[Deltamaster]

That someone would have to have been me as the bike has been in my possession from the start. I have not changed the gear, myself and can think of no time when anyone else might have had an opportunity. .

Thanks for the suggestion, though.

 

[joel]

Welcome
Did you happen to replace the rear tire to a bit larger one.
I had one replaced and the shop doing it didn't put the stock size back on once.
Might be something to check on.

 

[Deltamaster]

Good catch. I did replace the rear tire but I used one the same size as came off. It was a different manufacturer, though. Do you think that might be a factor? I will check again as I just replaced the tire again and will check the tire size as the shop picked the tire this time. I will check that against the size suggested by the manual. Thank you.