The original MTC clutch came with red springs and a set of 6 .025" shims and 6 .050" shims. You would install one shim of each thickness on the bolt/spring posts after installing the lifter plate but before installing the springs and bolts. This gave you a grand total of .075" of shim per spring. My original review was written based on this setup.
The second generation MTC clutch came with the same red springs and a set of 12 .025" shims and 12 .050" shims. You would install two of each thickness shim on the bolt/spring posts after installing the lifter plate but before installing the springs and bolts. This gave you a grand total of .150" of shim per spring and was done in response to some riders still experiencing some slipping with the smaller (.075") shim pack.
The current version of the MTC clutch comes with blue/black springs and no shims. You install this clutch and springs exactly like the stock setup with no worries about shims. After reading my original review here a few years ago, MTC contacted me and after a lot of emails, phone calls, testing and evaluation we settled on this kit and these springs as a better solution to some of the problems experienced by some riders.AfterthoughtsPros
Simply put, this thing grabs like a SOB. No more clutch slipping, much more burnt rubber and wheelies, lol...
Thanks to the VTX's hydraulic clutch the lever pull feels the same as stock despite the drastically increased spring tension
Shifting is improved, the best way I can describe it is shifting is much more "crisp", the bike seems to snap into gear
All the grab of a lockup clutch with all the "rideability" of a normal clutch
Cons
Slight lunge when cold - I have heard people mention problems with it grabbing too much when cold, but this clutch has only shown a SLIGHT lunge when shifting into first when the bike was cold. It's nothing serious as I've seen stock clutches exhibit this same behavior from time to time. I expect with a few more miles even this will go away.
Cost - at about $170 it's a little pricier than most replacement clutch kits out there. Despite this I will say that it's worth the extra money IMHO.
Tires - this thing grabs so good you'll be replacing tires more often from all the burnouts.