No idea, said theres no limiter which has to be wrong.
How come you didnt break a valve bill? That is very lucky.
very lucky indeed.. spring had broken on mine, hyrdro lifter pumped up cos it could, to make up the gap, and held that valve open.. so I had a misfire. stopped it, checked coil packs, plugs, it still did it, so trailored it back to garage to fix. removing head that valve was still jacked open.. once it drained down it closed, but I had springs to fit, so fitted them, and on dismantling the broken spring fell out in 2 pieces..
the breakage on mine was caused by a mis-selection where I buzzed the motor.. going from top of 2nd gear back into 1st when 3rd did'nt engage as at that moment the gear cable end on the box snapped off.. The dropped cylinder happend the following weekend, not at the time. Damage was most certainly done on the engine buzz tho at tha previous race.