I followed the wife home the other night (she was in her Blazer) and had to do about 73 mph to pace her. She swears that she set her cruise at 65 and her speedo ranged between 65 & 67. I rode to work this morning and paced the car in front of and the speedo was @ 70. Anyone else had this happen?

Quite common. The usual gang here says the speedo is about 10% off. I just bought a GPS and ya know what? They are right. I knew there was a reason there were so many cages passing me on the highway.

I haven't tried that yet. I bought a speedo off ebay and thought that it might have been from a different bike. Since I know I can adjust my speed accordingly. Thanks for the info.

I followed the wife home the other night (she was in her Blazer) and had to do about 73 mph to pace her. She swears that she set her cruise at 65 and her speedo ranged between 65 & 67. I rode to work this morning and paced the car in front of and the speedo was @ 70. Anyone else had this happen?

Yeah, one day they posted one of those Radar signs on my road - you know, the "Speed you're traveling is" signs that local law enforcement puts in now and again. Although it was December and 20-degrees, I really wanted to get a feel for how far it was off (I knew it was off). So I started around 25 mph, turned around & kept coming back at increments of 5mph faster until I hit 50 or so. As I recall, at the lower speeds I was clocked 3mph slower. Around 50mph it was 5mph. Probably for the best since I tend to travel around 10-15mph over the limit per the speedo if the roads permit (excluding superslabs when you have to do 80+ to keep up, eh?.

I have been a subscriber to Motorcycle Consumer Magizine for over four years. They conduct the only performance trials that I know of in any of the rags. In everyone that I can remember the bikes being tested speedometer was always three to five miles/hr faster that the timeing devices. Maybe its a manufactures conspiracy, trying to save us from ourselves. Anyway, very common to show five knots faster at 60.

yes, we have 2 vulcans. both read identical miles and mph, but both are about 5 mph off at 55, you are doing 50. at 65 you may be doing 59.
my toyota truck is exactly the same way. coincidence?
beavis