It's the gain you're after, nothing else.

In the UK most people use DynoJet dyno's and tend to use the DynoJet calculated HP at the flywheel figure.
This is something like 60bhp for a good, stock, fresh, deresticted NSR 250. Anything up to 66bhp or so for a carefully tweaked one. Steve's F3 monster makes 74bhp. For comparision a stock 1991 RS250 makes 72bhp and 1996 one makes 76bhp.

Some others use DynoPro's, which can either give a true rear wheel HP figure or a DynoJet calculated figure.

Very few other dynos are in use over here.
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