yeah, what are you trying to do? clutching is very limited on this sled. You can do some tweaking. I have 1 that I have tweaked a little. I want to do more, but it works ok enough that I have not gone further. My thoughts were to go to the later primary w/ flyweights. That might help? or the power block primary? or a comet replacement? any of these primary clutches are adjustable. if this isn't enough, a jackshaft rosebud modification to install a keyway & a new secondary would be next!