I went for the 3 piece spring clutch in the end, it turns out they last for a very long time, and are 200g lighter than the 1 piece type......also the 1 piece type give more grip the older they get.......I spoke to ricky grice and he also said the 1 piece type are not good for learners as when they are hesitant on the throttle, the crank assembly has a torsional vibration moment and tends to break the 1 piece clutches.......this link was interesting too.......I'm convinced the only reason comer sell the 1 piece design is because its cheaper to produce and they make huge profit margin on them, especially as they wear out quickly.
http://www.karting.co.uk/Notice/Mess...gID=0000474414
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