re. billet basket, it depends. If you're drag racing or launching it off the lights every day, then yes. If you're riding it normally (read that as hard racing, launching it hard but not all the time) then I wouldn't bother.
There are other things I'd look at first. Check all your linkages between your foot and the shaft going into the engine. Any play creates issues and can be minimised by bushes and new swivel joints.
My foot lever pivot point had worn oval and had lots of play. I bought a new bush that was a perfect fit for the bolt and reamed the hole out for the bush. It made a big difference to the play in the system
When you've eliminated this, pull the clutch basket and check the springs in the back of the basket. The gear that indexes with the crank is divided in two, and a set of springs take the slack out of the gear. Unfortunately haha, the 12 has a little bit of power and the springs get a hard life. It's not uncommon for the spring to get crushed and then you have a lot of play between shifts. I've never changed the springs but it can be done.
I've been considering modifying the shift star, but I haven't looked into this yet.
There are other things I'd look at first. Check all your linkages between your foot and the shaft going into the engine. Any play creates issues and can be minimised by bushes and new swivel joints.
My foot lever pivot point had worn oval and had lots of play. I bought a new bush that was a perfect fit for the bolt and reamed the hole out for the bush. It made a big difference to the play in the system
When you've eliminated this, pull the clutch basket and check the springs in the back of the basket. The gear that indexes with the crank is divided in two, and a set of springs take the slack out of the gear. Unfortunately haha, the 12 has a little bit of power and the springs get a hard life. It's not uncommon for the spring to get crushed and then you have a lot of play between shifts. I've never changed the springs but it can be done.
I've been considering modifying the shift star, but I haven't looked into this yet.
