Can anyone explain to me what pulses per cycle is all about?

I had an issue this weekend whereby I changed my rectifier from the fireblade one to a CB250N superdream one and when I plugged my Digidash back in it showed the revs as double what they should be.

I have re-configured the dash for 4 pulses per cycle which now works perfectly but for a fireblade it should be 2.

So what I am really asking is would changing a rectifier change the pulses per cycle but also I really would like someone to explain what the pulses per cycle actually means!

ta,
Rich.

presumably its the amount of pulses generated per revolution?

yeah I guess so but why for instance is a bike engine 2 pulses per cycle and a car is 4? and what exactly is a pulse??

And also would changing the rectifier change the pulses??

Rich.

This may help:
http://www.allaboutcircuits.com/vol_3/chpt_3/4.html

Quite interesting reading.

Thi smay be utter codswallop but on a car engine the trigger comes generally from the coil so a pulse occurs 4 times per 2 revolutions of the engine hence I would say that the pulses per cycle should be set at 2. On say the blade engine either this is a lost spark system or possibly the pulse is generated from one of the 2 coils supplying 2 of the four cylinders. If it is a lost spark system it would pulse 8 times for 2 revolutions hence the pulses per cycle should be 4. As I say I may be barking u completely the wrong tree!

Howler,

I think you are barking up exactly the right tree actually!! I too have come to this conclusion and MAC1 also told me to set it to 4 and it all works fine now!

Thanks for a simple explanation or how it differs from the car engine, at least I now understand why a bit more than I did!!

Rich.