Primary gearing and Dyno figures

Fast Eddie said:

Gents (especially Mr Comstock):

I want to do a Dyno run soon to get a 'before' figure for my bike with its current (already fairly trick) sate of tune.

Then I want to re-work or replace the head over winter, with no other engine changes, and put the same bike on the same Dyno, for a nice back to back comparison.

However, I also want to change my primary belt set up over winter, to raise the primary gearing (up from a 32 tooth front pulley to a 36).

My question is: will the change in primary gearing effect the Dyno results in any way?

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Fast Eddie said:

Thanks Jim, I guess I thought it might effect the torque at any given engine rpm, since the relationship between rear wheel rpm (where the measurement is taken) and the engine will have changed.

If there is little or no effect, I can discount this form effecting the outcome.

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