Wondering if anyone can help me with this issue. Got back from a little road trip and think there may be a problem with my speedo. I have a HD combination Digital Speedo/Tac 4in model in my 11 FXDWG. At the end of the trip my speedo is registering 1156.5 and my buddies a 14 Street Glide Special is reading 1199.9, that is a 43.4mi difference. Even though we road the exact same distance. my speedo always read about 1-2mi below the speed limit but my buddy was cruise controlling it at about 1-2 mi over the speed limit. I asked about half way through why he was going slower than the limit and he informed me he wasnt. Not sure how I go about correcting this issue...if there even is an issue, as it could be his bike thats off. but considering his is newer than mine and I have swapped out the speedo i feel its more than likely me. any suggestions?

 

That's around 3% difference, so to be frank it's within the expected degree of accuracy of speedos. They are not precisely accurate and never can be, due to variations of tyre diameter between tyre brands, plus tyre wear. If you were to do the same excercise on your own bike with a brand new tyre, then again with a worn out one, there will be a difference of around 3%!

So IMHO there is no problem, ride on and enjoy.

 

Well I guess I wont worry to much about it then. It wasnt bugging me before, so i guess its not really an issue. Thanks for the input.

 

If you want a bit of fun, compare your speedo and mileage with a gps - you'll get a third set of numbers to play with! The gps will be more accurate.

 

I do have a GPS watch I got for when I run and its pretty accurate/consistent. Ill have to give it a try. But Im not to concerned with it. I don't think Its something that puts me a risk for injury or worse my bike not starting.

 

I see in your signature you're using a tuner; you should be able to change the speedo calibration in one of the setup menus. Trust GPS for your most accurate reference.