Question about 2 speed jackshaft

Kenny1

New Member
#22
OK OK OK!! I get it! The second clutch isn't being engaged by the engine but rather by the jackshaft itself. Only once the jackshaft has reached a high enough speed to expand the shoes in the clutch does the engine start sending power to it and then through the jackshaft. The clutch is being freewheeled on the outside until it engages. The shaft is only spinning half the speed as the engine, so when you get into the high revs it will get the second clutch going. Ok, makes more sence. I wasnt taking into account that at firtst you are using the second clutch almost backwards in a way. Thanks guys!
 

MINI-MATIC

Active Member
#23
Re 2 Speed

HI KENNY,GLAD YOU FIGURED IT OUT,THE ENGINE WILL TURN TWICE AS FAST AS THE JACKSHAFT AS LONG AS THERE IS EXACTLY TWICE AS MANY TEETH ON THE FIRST GEAR ON THE JACKSHAFT COMPARED TO THE DRIVE CLUTCH ON THE ENGINE,OTHERWISE THE RATIO WILL VARY A LITTLE!.JUST TO LET YOU KNOW,THE FAIRBANKS DRIVEN CLUTCH WORKS IN A TOTALLY DIFFERENT WAY THEN THE COMET.THE FAIRBANKS IS LIKE A TYPICAL CLUTCH IN HOW IT'S DESIGNED AND WORKS,ON THE OTHER HAND,THE COMET IS JUST THE OPPOSITE!.THE BELL "DRUM" HOUSEING ON THE COMET CLUTCH IS SET SCREWED TO THE 5/8 SHAFT.WHAT IS FREE SPINNING IS THE SHOES AND SPROCKET WHICH ARE ONE UNIT.WHEN THESE SPIN FAST ENOUGH,THEY ENGAGE. ON A TYPICAL CLUTCH,AS IN THE FAIRBANKS,THE BELL OR "DRUM" AND THE SPROCKET ARE ONE PIECE AND FREE WHEEL,THE SHOES AND INNER ASSEMBLY ARE THEN KEYED TO THE SHAFT,IN THE CASE OF THE LIL INDIAN MINI-MATIC SETUP,THEY USE A WOODRUFF KEY,THE KIND THAT ARE SHAPED LIKE A CRESENT MOON ON ONE SIDE AND FLAT ON THE OTHER..:grind::grind::scooter:
 
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