Kris01 wrote on 09/25/14 at 18:28:17:2240:60 means the speedo cable must spin 2240 times for the gauge to read 60 mph.
Stock 140/80-15 = 74.829" circumference
846.731 rpms (of the tire) at 60 mph
2240/846.731 = 2.645
The stock speedo has a ratio of 2.645:1. I doubt the 2:1 ratio speedo is anywhere close to being accurate.
Sorry, I don't agree.
2240/60 means an assumed 2240rpm (turns per minute) to read 60 mph.
By your own calculations, the Savage needs:
- 846.73 revolutions of the tire
- multiplied by 2.94 (belt drive ratio)
to read the same speed.
846.73 x 2.94 = 2489/60 (let's round this off to 2490/60 or even 2500/60)
So a 2240/60 speedo should read 2490/2240 = 1.11 11% faster than you are actually going.
The sppedo I fitted reads 10% slower than I am actually going, even though I now have a 2.88:1 chain drive and a 150/90x15 rear tire.
Had I a stock bike, it'd be reading 15% slower !!!
Explain THAT to a cop !!!