NOTE: This is our initial report after fitting
Karl's first production kit into a 750GT back in 2001. As of November
2013, Karl has retired and Bevel Heaven has officially bought this product
from Karl and we have finished production and are ready to ship.
to purchase and see more photos etc THANK YOU
MMS hydraulic clutch
conversion kit for bevel drive Ducati twins
By: Ivan Thelin
Photos/install help: Steve Allen
The MMS hydraulic clutch conversion kit is a replacement
stock clutch lever, cable, and throw-out arm on bevel-drive L-twin Ducati
motors. This kit replaces the parts with hydraulic equivalents. The advantages of
this conversion are: fewer moving parts, smoother clutch release, much
easier lever effort, less maintenance. The kit shown in the photos
is not a prototype but is considered pre-production (as it does not have
an MMS logo etched in it). It is virtually identical to the
This kit included the following parts:
- CNC milled, black anodized alloy slave cylinder
- CNC milled alloy piston with square section
O-ring and hardened steel insert button
- Goodridge braided stainless steel hydraulic line
with clear vinyl coating
- Goodridge chromed line fittings (adapter and
- Brembo master cylinder assembly w/ polished alloy
- Stainless steel allen bolt with nylock nut
OPTIONS: Bleeder banjo bolts, black
lever, black or clear line coating, line length
PRICE: $479 (yep, I paid full price... I am
not sponsored by MMS). Quality of all components is excellent.
Install was straight forward (but not for the novice mechanic). It took
only hand tools (a die grinder would have sped up things).
- Removing the gas tank and saddle will speed up
work but may not be required.
- You will need to use a few nylon zip straps to
tuck the hydraulic line neatly out of the way, and keep it away from
hot motor parts.
- The trickiest part of install was grinding a
small notch in an aluminum web on the inside of the gear selector box
to clear one corner of the slave cylinder. This is where having a die
grinder would have been nice. We used a small, coarse halfround file
instead. It took about 15 minutes of careful fitting and filing. This
may not be necessary on square case motors.
- Filling the system with fluid was easiest after
routing the line, but before final assembly of the piston. Having two
people really helped here, as you will want one person working the
lever and filling the reservoir, while a second person assembles the
piston assembly down by the RH side of the bike. This person pushes
the lightly greased (we used Redline Assembly Lube) piston in
carefully, then turns it to allow trapped air bubbles to float back up
the line to the reservoir. It's easier than it sounds. We used MOTUL
Racing 600 Dot4 brake fluid, but any good hydraulic brake fluid is
compatible with this kit.
- Lastly, it is critical that you follow Karl's
setup and adjustment instructions. This includes shimming or adjusting
your clutch spring plate and springs for perfect release. The outer
plate needs to be perfectly flat when it lifts... that is
"true" like a wheel, for a clean release.
- Everything went slickly, and after about 2 hours
it was time for a test ride.
Results: This kit is amazing!!! The
hydraulic clutch really tamed my GT's heavy clutch springs, transforming
the pull entirely. It is much easier. Not as linear as the
cable, the kit gives a bit more of an on-off feeling, which I got used to
within a few minutes. Gear selection seems noticeably easier as
well, including locating neutral at a stop. Looks like I'll be
getting a lot more riding pleasure from my little 750 GT from here on out.
Contact Bevel Heaven to purchase this kit for your Ducati bevel twin