I/S vs Standard Trigger Wheels

[sailed2japan]

I was woundering why you can only install a 4* trigger wheel in an I/S, but you can put a 6* in a Tourer or Standard. Is the I/S already advanced 2* over the Standard?

[X Ring]

I think, repeat think, it's because the I/S ECM advances the spark faster on the I/S than the ECM on the Standard/Tourers does.  Installing an I/S ECM on Standard/Tourers is a common mod.

Marty

[sailed2japan]

Cool, that's exactly where my hampster wheel was spinning to!

[98valk]

I was woundering why you can only install a 4* trigger wheel in an I/S, but you can put a 6* in a Tourer or Standard. Is the I/S already advanced 2* over the Standard?

the search function is your friend. this has been addressed with the advance curve charts 100s of times.