tri z motor improvements???

[mike from long island]

i have gotten two complete extra motors and a good parts one. the motor i want to use will be taken completly apart. cases split. i am going to put all new bearings and all. anything i can replace i plan too.this will take some time to get parts and the money but this is ok. i have a strong running motor built i the Z already that i ride with. i have a jug that has been modifed and dont think ill use.have a good one that has low bores done to it also. now here are my questions

1- can i lighten the crank?? (like i did with my banshee)
2-whats a good clutch kit to get?
3- again what piston?
4-how to know which yamaha wrench report to use?

any help or comments are appreciated in advance thanks mike i am sure ill have more ??? as i get into the motor

[Tri-Z 490]

A good clutch to use is the Barnet dirt digger. If you can't find one for the Tri-Z I think its the same for a 1982-1987 YZ-250 and 490 but I am not 100% positive. As for the piston Wiseco Pro-Lite is a good one.