The old MTC clutch for the VTX
including the original red springs

This is my evaluation of the MTC clutch available for the Honda VTX. You can see how to install this clutch here.

I decided to give this clutch a shot after hearing rave reviews about it from other knowledgeable folks who were using it as a substitute for a lock-up clutch on high power motors. It has worked successfully on motors with high compression pistons and cams, over-bored motors, turbocharged motors and with my latest attempt I can verify that it works on a motor with a 40 shot of nitrous.

Since this clutch has been available through MTC, there have been a handful of people who claim to experience slip from them. I have never experienced slip with mine. I consider myself a very aggressive rider, so naturally this raised a lot of questions. I’d like to thank everyone from the online forums who helped discuss, test, troubleshoot, etc the various aspects of the clutch system in an attempt to resolve these issues. Without the time and effort invested by all these people, we wouldn’t have the knowledge and understanding of the clutch system that we have now.

After the previously mentioned discussions, testing and troubleshooting, I worked with MTC and some changes were made to the clutch kits.

• 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 of this clutch was written based on that 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 the slip still experienced by some riders with the smaller (.075″) shim pack.
• The third generation MTC clutch comes with blue/black springs and a shim pack, but the shims are not intended for use unless you have a higher than stock power application. You install this clutch and springs exactly like the stock setup with no worries about shims. These were the springs MTC settled on after several other riders and I did some measuring, testing, etc. The springs are designed to be a “middle ground” solution that falls somewhere between the harshness of the MTC red springs and the poor performance of the stock springs.
• Edit 6/28/11: I got an email from my contact at MTC today, he had this to say… Our latest shipment of springs are not black, we were told that this was a process that our supplier no longer provides as it adds nothing to the function of the spring. Rest assured they are the same rate/pressure springs we’ve been shipping for the past few years, just a new batch. There is nothing different about these springs other than the color or lack thereof. It’s been almost 3 years since a kit left here with the red springs, so I doubt anyone has an old one lying around on their shelves. So from here on out the springs are no longer black with a blue stripe – they are either silver or silver with a blue stripe. There is no other change to the springs except the color.
• The current recommended MTC clutch setup comes after a lot of additional testing. Verbatim (from the forums) was good enough to take some of the test results we already had and then do a lot more testing on top of that. His measurements and discoveries showed that the best setup is the MTC blue/black springs and .075″ of shims per spring (obviously with the MTC clutch’s fiber plates).

You can read more about the various “stages” of the MTC clutch and how other riders and I worked together with MTC to get improvements made on the forums.

Afterthoughts
Until now, I have always been a believer in the spring swap as a sure-fix for most bikes with clutch slip, and at ~$20 for the springs I still consider it as an option before replacing the entire clutch. The only exception to this would be on a bike that has experienced slippage for a long time. Under this circumstance, there is a good chance the clutch plates are burned and worn out. Once this happens, springs alone won’t be enough to fix the problem. With that said, anyone who is still experiencing clutch slip with the new springs, anyone needing to replace their entire clutch, or anyone with motor mods that require a stronger clutch should definitely consider the MTC – it would definitely be my choice. I have never felt a stock clutch grab and handle as nicely as this one. Even on a bike running a 40 shot of nitrous it grabbed with no detectable slip.