Our bikes have speedometer's?


LOL

 

however there is a much easier way to identify ur actual speed without having to drive for 2 hrs to see how far u actually go ...simply travel on an interstate with designated mile markers...reset ur trip right at one mile marker and check where it is when u pass the next...keep checking them...u can get a good idea how far its off by traveling 10miles worth of mile markers...of course the further u travel the more accurate ur guestimation of how far off it would be...if u travel 10miles worth of mile markers and ur trip only reads 7miles then ur speedo is off by 30%...however if u travel 100miles worth of mile markers and ur trip only reads 77miles then you know your speedo is off by 23% so its all about accuracy...i had to do this with a truck i had that someone put larger tires on it



reevesna has the right idea but wrong how to do it. what you need to do is get on the interstate and ride at a constant speed for say 10 miles. Then, divide the 10 miles by how long it took you to ride that far. this will give you your speed for that distance. But to be more accurate you will have to travel further and do the same thing i just mentioned. The way reevesna had you doing it would have been incorrect. resetting your odom at one mile marker and checking it at the next will have no effect because your tires are not getting bigger or smaller (i assume the tire sizes were not changed when the sprockets were changed). Now if the tires are bigger or smaller then yes it will affect your speedo. however just by changing the sprockets will not, or should not because the tires are still rolling over the same distances as they were before which has no affect on speed. Bigger tires will roll farther, so your disance will be shorter...smaller tires will roll over a less amount of distance and your mileage will be more. your speed would also be affected by that. what reevesna said about the truck having bigger tires on it, is what im talking about. since the tires were bigger than the stock tires that the speedo was probably calibrated at, the speed would be off. do you get what im saying? sorry for the whole "school" lesson, but i didnt know how else to put it other than this...if i am wrong some how, someone please correct me.

 

Well, you're 1/2 right. Different tire sizes will affect the speedo slightly. Usually less than 5%. However if the speedo pickup is reading the counter sprocket -- then sprocket size DOES affect the speedo.

A sprocket has a fixed number of teeth. So for example the front has 5 teeth and the back has 10. Every time the front turns 2 revolutions the back turns 1. Change the back sprocket to a 15 tooth. Now the front spins 3 times for every 1 rev of the back. Definitely affects the speedo.

 

Speedo Healer from cal-sportbike.com, works like a charm!!!!

 

Nipz , the amount of revolutions on the crank is called RPMs not MPH. Sorry mabey you meant somthing else. the speedo would actually but run off the trans. yea it is affected.