Seems I am having a very similar problem since my 21 come back from the dyno. One minute its running fine, the next its holding back at about 5-6000rpm for about 3 seconds then bang it goes properly again.

Powervalves are all turning properly, carbs are all clean, bike is standard apart from re-jet, airbox mod (which I want to put back to standard if I can find a standard airbox lid - anyone got one?) and wire splice.

Its the same in all gears so doubt its the splice causig the problem, at least not the gps one. The dyno session gave a power output of 54bhp but had a little flat spot at 9k rpm which had 40 bhp and the torque also dropped slightly at the same time.

Anyone know if/how snagger fixed the problem? I am guessing its an electrial problem somewhere but just wondered if anyone has any ideas where to start.

Cheers

Leigh