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RockStar
01-19-2006, 07:34 PM
A buddy-o-mine who just bought an S2R1000 is looking at clutch slave cylinders.

He came across an STM....Anyone have experience with these/compared to Evo's

pros/cons?

thanks.

Mat
01-20-2006, 07:03 AM
STM is new to me but this begs a question....why replace the stock one??
While in the past Mother Duck has had some pretty
flakey clutch slaves, the ones being made recently
seem to be trouble free.

RockStar
01-20-2006, 08:31 AM
STM is new to me but this begs a question....why replace the stock one??
While in the past Mother Duck has had some pretty
flakey clutch slaves, the ones being made recently
seem to be trouble free.
1. pull weight.
2. pull weight.


on my S4R (and most Duc's) the pull, or draw, wieght is what, like 5lbs. Evoluzione drops it to a feather pull by 50%.

Better control, faster, more responsive.

Mat
01-20-2006, 02:59 PM
OK, hydraulics are mechanics.
Pull force is a function of two things....
1. Mechanical advantage (ie how far open you open the clutch vs how far closed you pull the clutch lever.
2. Friction....carboxilated nitrile, teflon impregnated nitrile, plain old buna.
The best answer,in my book....build the weenie muscle in your left arm and you have the best answer.
Otherwise, buy a Honda automatic.

RockStar
01-20-2006, 03:30 PM
Verbosity is rather pornographic, pugnacious and recondite. I plead herein for comity and shy from taking sesuipedalian form.

Ergo:

Stock clutch pull is stiff and hard = slower, regardless of arm strength. This is a physiological discussion which I'd be glad to enter. Motorneuronal growth and slow-twitch response is limited to the length and size of a muscle.

In other words if I could use my quadriceps to pull the clutch faster and smoother then I just need to run as fast as Jackie Joyner-Kersey.

After-market pull is lighter and smoother throughout the range: thus mechanically adjusting for the poor physiological interface with the machine.

Conclusion: increased resevoir size and fluid displacement during execution
is race tested, proven, and an acceptable practice. Not to mention making light to light traffic driving a helluva lot easier.

Back on Topic however:
The only real difference I see between Evo and STM is cost and maybe 2mm worth of plunger depth.

Mat
01-20-2006, 03:43 PM
Conclusion: increased resevoir size and fluid displacement during execution
is race tested, proven, and an acceptable practice. Not to mention making light to light traffic driving a helluva lot easier.
.

Uh...OK, I am stimulated.
Bore VS Stroke is not rocket science.
What the heck did racers do before hydraulic clutches???.....RACE!!
I am sure that the after market slave will make you the faster rider....or not.
But, I am open to spending good money for incremental improvement.
If we are looking for real dollar-wise-speed...buy a UJM and do it today.

RockStar
01-20-2006, 04:28 PM
Well. I've used both stock and Evo. I can't for the life of me figure out why I didn't switch to the Evo far sooner than I have. (thanks tjducati)

As Keith Code says I 'invest less' to gain more time for making better judgements.


But as I stated the original question was to solicit personal experience with STM at the request of a friend....he's since chosen the Evo. And you're right, it's not rocket science, so I'll be passing on what MatrixDon passed on to me...some good mechanical know-how. (thanks Don ;)

...retiring from this thread.

Mat
01-20-2006, 04:42 PM
Lord, I love retirement...from anything...anytime...
I am going to try an EVO slave, just to see what
this energy is all about.
Mutt

CINDESMO
01-20-2006, 07:49 PM
If you have ever been in stop and go traffic with a dry clutch Ducati, the aftermarket slave cylinders rock. I have the Evo one personally.

Mat
01-20-2006, 10:12 PM
Great wisdom!
I have done the timeless stop-and-go thing.
Slipping into neutral makes nasty clutch noise
so I would far rather pull in the clutchy lever.
Thus I understand the value of the light pull.
Ok, but noise is not why I ride my Ducky tootsie.
Oh well...so it be....the light touch sounds good...at what price?