Some dyno charts to give an idea
This is a LT500R with a custom shearer/q pipe, stock carb, cut head, mx ported, boyeson reed.

This is a banshee with fmf, trail port, cut head, vf2, single 38mm pwk carb, +4 timing

Notice the a/f curve, see if the guy has that, and use it. They are worth it for tuning. Also need to make sure the guy knows how to read the curve.
Pics of the quads on the dyno




Video runs

