My 670HO just doesn't go as good as it should. I am trying to figure out what to do to make it pull harder. *My current clutch set up is as follows: *stock arms, stock 16.4 gram pins, 280 ramps, 230/320 (pink/purple) spring, stock 53/47 helix w/ 19 lbs of preload, Goodwin teflon buttons. *This is very similar to a set up that I ran on a 97 mxz 670 but it pulled much harder on that sled. *I am considering going to 18.5 gram weights from Fast but I don't understand why I should have to run that much weight with the above set up. *Any help would be appreciated. *I don't like getting beat by my old 97 MXZ670 that now belongs to a friend.

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670hoth, get rid of the 280's, *try *286 ramps , 200-320 or 200-290, 16.5 pin, 50 deg *helix, that should be a good start.

I tried the 280 's and found that the combination of the ramp profile and the 53 deg helix were too much for the sled to pull with stock gearing out of the hole. Try a 24 tooth top gear with a straight 50. That works much better.