Re: Super Simple Tacho
I've already done the maths and worked back through the jackshaft ratio and the engines primary reduction gear ratio (big and small gear) to tell the bicycle speedo what circumference it needs to be using for an accurate readout in kilometers per hour, that reflects engine rpm.
Just do my conversion, follow the instructions and you'll be amazed that the bicycle speedo reads the engine rpm correctly.
I've taken my bike to three engine shops and they've confirmed with their electronic tacho's hooked up to the sparkplug lead that the bicycle speedo is in fact reading the correct rpm's
Just do the maths yourself and you will understand how it works and why it works - "there is no problem".
Last edited by Fabian; 09-30-2009 at 08:25 PM.
Reason: typo error