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Sporty drag racing

  • obisteve
    obisteve
    1 year ago
    Interesting, most of them are using the pre 1994 frame, curved rear mudguard supports. Maybe it's a touch lighter.
  • HOG63
    HOG63
    1 year ago
    I also wondered about chain drives and type of clutches. And a quick shifter would do wonders for times/final speed. 
  • obisteve
    obisteve
    1 year ago
    With closer viewing, only a couple seem to be 4 speeds, screw in primary case inspection plug and slightly different shift shaft location. So most of them come from a 3 year period, 91 to 93. Strange, it's not the best years for free flowing heads.
    It's only a 480 ft track, 160 yards, most are only making 2 gearshifts. Quick shift will help, but a spring loaded killswitch with clutchless changes will be almost as fast.
    The year I won top street eliminator at Aratula 1/8 mile, 220 yds dirt drags I was crossing the line at very top of 2nd on a 4 speed.
    With the clutch, a Barnett extra plate clutch that eliminates the spring plate will handle up to about 100 hp as long as your using a wet clutch compatible gearbox oil. It's possible to go over that with a Sporty, but you're spending big bucks to go there.
    Thanks for posting the link, I enjoyed it.
  • HOG63
    HOG63
    1 year ago
    Quoting obisteve on 22 Feb 2023 10:49 AM

    With closer viewing, only a couple seem to be 4 speeds, screw in primary case inspection plug and slightly different shift shaft location. So most of them come from a 3 year period, 91 to 93. Strange, it's not the best years for free flowing heads.

    It's only a 480 ft track, 160 yards, most are only making 2 gearshifts. Quick shift will help, but a spring loaded killswitch with clutchless changes will be almost as fast.
    The year I won top street eliminator at Aratula 1/8 mile, 220 yds dirt drags I was crossing the line at very top of 2nd on a 4 speed.
    With the clutch, a Barnett extra plate clutch that eliminates the spring plate will handle up to about 100 hp as long as your using a wet clutch compatible gearbox oil. It's possible to go over that with a Sporty, but you're spending big bucks to go there.
    Thanks for posting the link, I enjoyed it.

    If I ever drag raced a sporty, I would put a much smaller front sprocket and actually start off in second gear. It’s the 1st to 2nd shift that is the hardest on the gearbox. No chance of a busted 2nd gear tooth. Doable I reckon with a Hammer 1250 or 1275 kit and a QuickShifter. 
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