Right.....here's a wierd one!

I refitted my Digidash this evening (after it has been repaired for a minor fault) and I noticed that the rpm was reading way above what it actually should, the engine normally idles around 1100rpm but it was reading more like 2100rpm!

The only thing I have changed is that I have fitted a Honda Superdream rectifier and this has an extra black wire that has to go into a circuit which is made live with the ignition. I chose to use the blackwhite wire feeding the CDI and coils to wire it into. The Digidash RPM reading was perfect before this.

Now after testing all the wiring I finally decided (because I couldn't think of anything else!!) to change the pulses per cycle on the Digidash from 2 (which is should be for a bike engine) to 4 and then the RPM seems to read what it should!

Now I can't see why but would wiring the rectifier into this circuit make the pulses per cycle different??

Any ideas greatly appreciated!!

Wiring diagram here if anyone wants a look http://www.shortshouse.co.uk/WiringDiagramv19.pdf

ta,
Rich.

[Edited on 2/9/05 by shortie]

It shouldnt. But then...............!
Have you ran it up with a voltmeter across the battery, just to check it regulates to 13.6-14.2v nicely, just in case its overcharging (with/without extra wire connected)?

are you on MSN colin?

I haven't tested the voltage without the wire, with it connected Digidash reads 14.2 - 14.5 which is perfect