took my spec 4 about 1000 miles to quite chattering.

grabs hard, little harsh on take offs...alum flywheel doesn't help....but its nice to not have to worry about the sprung hub

 

spec have worked for me so far....
i will be trying monster next time for sure

 

I loved my spec III (not the +) 18+k and held alot more than it should have.
600+hp/tq leaving off the rev limiter with a 4000lb race weight. It started to slip the last race day of the year. I am looking at the twins but I don't have the $$$