I spoke to a dealer today to book my car in for the annual service and we got to chatting about the Centa unit.
Apparently it needs a completely different fly wheel, which is lighter and therefore improves throttle response and also has a centre actuated clutch release bearing and not the fork type used on the old style compensators.
This is why it seems to take a long time to fit and costs so much.
Grease part number is: 4003/2017
Tanks for that DAB !
The clutch throw out mechanics have no bearing on what compensator one would have. The throw out bearing and fork is located on the downstream side of the clutch and flywheel. Although most modern cars with hydraulic clutches now use a small slave cylinder mounted around the transmission input shaft support rather than the old style fork with an external slave cylinder.
I would see no reason to upgrade the mechanics of the throw out bearing because of the comp upgrade. The fork style has worked well and there is no load on it more or less regardless of the motor etc.
For grunting around at lower rpms, which the S&S is very good at doing, a heavier flywheel tends to increase the drivability for cruising, but the light flywheel does come into play when looking at performance. When looking at the v-twin motors, most of the crank assemblies are 30 plus pounds. I would guess this to be lighter than the Miata 1.6L or 1.8L motor usually used in front of the 5 speed you use. Now the S&S I believe uses a forged one piece crank and uses automotive type connecting rods versus the Harley three piece crank with the twin straddle type rods on the same crank pin centerline. The S&S may be lighter than the Harley version, but both still only had the alternator rotor as an external flywheel, so they were overall a lot lighter in rotating mass than the way the M3W is setup. But still I would believe that the extra flywheel weight would be a plus for driving and not a negative.
I'm going to speculate a bit here, but if you had a lighter flywheel in a M3W, I would believe that more of the crank pulses would be transmitted through the trans and into the driveshaft and BB. The heavier flywheel, in my mind, would work to dampen the pulses and keep them in front of the flywheel and in the compensator; thus allowing less ratcheting of the transmission innards.
Maybe with a 6 speed and lower gears a lighter flywheel would be beneficial, like in hill climbs etc.
Just don't see the M3W ever having a crotch rocket type performance. Although Harley has done wonders with the V-Rod in their NHRA drag racing as they usually trounce the Suzuki high revving competition.
The Centa works similarly to the Harley style comp as it stores and releases energy pulses from the motor in a somewhat smoothed out manner. The Harley comp has the Bellville springs with the ramps and the Centa uses inner pockets on the shaft and matching pockets in the housing with four rubber logs forced inside each of the pockets. The squishing of the rubber logs back and forth does the same as the ramps pushing back and forth against the spring pack. But theoretically there are no wear parts on the Centa or metal to metal, unless of course the four rubber logs chomp up and disintegrate.
I've not seen any "assembled" pictures of the Centa comp, but I can imagine the shaft being splined and bolted to the crank and the end of the shaft just terminates as "X" inches. The housing I see bolting up and being perfectly centered on the motor side of the flywheel; hence the possible need for a new flywheel with the Centa. I then see the four rubber logs being held in the four shaft pockets near the motor end and the trans and motor are then slid together feeding the four logs on the shaft sliding into the Centa housing. Once they are about in, the rubber log retainer would be removed and the motor and trans would then be mated up solid. The shaft would be perfectly centered within the perfectly center housing with the four rubber logs as the only thing connecting the motor with the trans flywheel. It sounds like a great design and should be very trouble free. I'm sure that from what I read on the Centa website that they have decades of experience and providing the "right" durometer of rubber would be no issue for them.
Sorry guys, I'm just rambling here as if I were talking to someone and he's not answering me right back...
I just don't see the M3W as a high performance vehicle. I would think that a Polaris Slingshot with a "like" size motor would blow the doors off the M3W, but I could be wrong; as I am most of the time...
