The two brands that I recomend are STM and MPL. Both are awesome aftermarket clucth slave units!
The STM is advertised as giving a 25% reduction on clutch effort / pull and the MPL as 30%. Both are made out of billet aluminum and utilize state of the art seals that are FAR superior to those of the OEM slave unit. So you never have to worry about them leaking, which was a common problem on earlier model OEM slave units. The STM is more readily available within the US than the MPL, and retails for $200. If you shop around you can generally find them selling online for around $190. The MPL is harder to find in stock within the US. They do pop on eBay quite frequently and often with no reserve. The auctions usually ends within $140-$170 depending on the demand and qty out for auction. Retail the MPL is listed at $200. The build quality on both units is TOP NOTCH! Not only do they work great, but are impressive to look at as well. Another brand that’s also very reputable and one that I have personally owned is the Yoyodyne unit. Built with similar characteristics as the STM and MPL, the yoyo unit will offer you around 25% reduction in effort. Price wise, the Yoyo will set you back a hair over $200.
The one brand that I’m not too found of is the Evoluzione, or better known as the Evo model. I had this unit, but found this unit lacking the advertised 20 to 25% reduction in clutch effort / pull. Fact to fact, when compared to the other brands I had owned (STM, MPL, and the Yoyo) it was the least effective clutch slave I have ever owned. I literally gave it away, that’s how disappointed I was with it. The Evo also doesn’t have an internal spring, and was the hardest to bleed out of the bunch. On the pro (somewhat pro) side, the Evo offers a 10 year warranty against leaks. That may sound like a plus, but the truth is the Evo units internal cylinder has three rubber o-rings, which for the most part won’t ever leak, and even if they did, the shipping charges you would face in getting the unit back to Evoluzione for repair, would cost more than replacing the o-rings yourself. We’re talking about $1 at the most for all three o-rings and that’s full retail.
Installation for most all clutch slave cylinders is very straight fwd. You have three bolts holding the unit to the engine, and one banjo bolt on top. Swapping out the unit shouldn’t take you more than 10-15min. The bleeding process is very straight fwd, granted you’ve bled something similar (ie: car brakes) prior. With a simple bleed kit you can pick up from most any car parts store, you can have the entire job done in less than 30min. With a more advanced vac-bleed system, you can have it done in half that time. If you’re not much of the DIY’er, any car or bike shop could do it for you and I can honestly say, you wouldn’t pay more than an hours labor charge TOP for the service. I’ve done it so many times, I could probably knock one off in less then 20min.
OK last but not least, the warranty question – An aftermarket clutch slave cylinder will not and CAN NOT void your vehicles warranty covereg in ANY WAY! Its against the LAW! The Magnuson-Moss act of 1975 states very simply, no manufacturer can deny you warranty coverage because you as a consumer have opted to change a part on your vehicle, for a part that was not made by the manufacturer. If they do deny you coverage, they must prove without a reason of doubt that the part you installed was the DIRECT cause of the problem in question.
In other words if you install the clutch slave and a week later your bike is stalling out, Ducati CAN NOT by law deny you warranty work to fix the stalling problem, unless they can prove that the clutch slave is the direct cause of it. In such a case, the clutch slave would have NOTHING to do with a stalling bike (unless of course it was not engaging), but for the sake of argument let’s say it’s a problem with the ECU, they MUST cover the repair. It’s the LAW! Now on the other hand, lets say you swapped out the ECU with an aftermarket one and then you experience stalling issues and the dealer points out the ECU is the problem, then you’re out of luck, but ONLY for the ECU’s warranty. If you’re headlight is not working, that’s an unrelated issues which MUST be covered.
With any aftermarket part or mod, you have to ask yourself, what are the pros and cons. The clutch slave swap is one with very little risk and one that generally wont effect the operations of the engine, when installed and setup correctly. On a scale of 1 to 10, 1 being the least problem some or “warranty concerning” should you have any, and 10 being the most (dealer red flag), the clutch slave swap is a 1 all the way! In fact most dealers sell and push aftermarket clutch slave units because they themselves are Ducati owners and know the benefits.
So to sum up my ramblings, aftermarket clutch slave cylinders = HUGE PLUS! Highly recommended! I have one available for sale (check the classifieds section of this forum). If you don’t want mine, no hard feelings, get yours new from someone else – just get one!
You will thank me!
Oh and here's a pic of the MPL unit that was on my 999....