So... I finally had time to yank the clutch on my smallie... I know Dayn can share my appreciation for sheared woodruff keys. I'm not sure how I finished that last race - it must have shit the bed as I rolled into the pit. Whatevs. I ran a 4 plate single spring that I pieced together last minute for that last one. I was out of supplies and there was no time, so I ran 2 corks and 2 carbon - alternating in the stack. Motul transoil instead of 30weight. The clutch was slippy for the practice day, but then came on like magic for the race day (when it counted). In pulling the stinky beast apart today, the carbons were pretty whupped around the edges, but the corks were not. Gonna try the DRT outer plate that supposedly lets you run 5 plates. We'll see how that goes...
DRT outer plate looks impressive (to me) in how it works. If you follow the instructions, you can use 5 thin or 4 regular plates. Having a good amount of spare steels in a couple different thickness handy was a good idea. I mocked it up both ways and had good separation (no binding) with 4 and 5 plates. It was 5pm when I got it together, traffic and weather didn't really allow me to really open it up and get on it as hard as I wanted, but it seems to already be holding on a bit better. 5 plates in a smallframe sounds pretty ripping in theory... Getting a clutch to actually hang on has been a big problem for me this last season. I started with a uprated single spring 3 plate, tried out a 4 plate for a minute, put my eggs in a basket with an XL2 6 spring for a few races and then blew that up and cobbled together a single spring 4 plate for the last bout. Many many mixes of carbon and cork inbetwixt with not a lot of promising results. You can make a cylinder produce a fuckton of power, but if you can't translate that to your rear wheel, it doesn't mean much.
So have you had any more test time on the drt setup? I am thinking of just going all out and springing for the falc clutch. Also have my eye on the quattrini super duper setup with the two big springs, then using the semi hydraulic clutch cable. I just want to use something I know will work.
I had my share of clutch problems this year. Firs was the nut coming loose then I thought I had the same problem but it turned out that the plates just plane wore out. So basically the Malossi 4 plate lasted 2 days on the track and the standard 3 plate I replaced it with only held on for a day....not good.
I'm a bit cheap so I made up an adapter to take 8 really strong springs into a standard clutch. I'll post some pictures of it tonight. The springs finally showed up so I should be testing it soon. If this fails I'll likely get the DRT clutch. It looks like the most reasonable option to me. The Falc is a bit on the expensive side though likely worth the money and I read on a forum somewhere that the Quattrini didn't hold up all that well.
The 5 plate (DRT top plate w/ a single spring) seems to be holding pretty good, but I think I need some more seat time with it to really know - and this weather + wet leaves is not my first choice for riding conditions when it comes to ripping around on that bike... I'm with Dayn - it would be nice to get more than a day or two of riding out of a clutch.
I just won the auction for one of the hebo semi hydraulic clutch thingies. now I can run a crazy stiff spring, anyone wanna offer suggestions for the best combo now that tension isnt a factor? they say hydraulic clutches self adjust and last longer too. hmmm.
Thanks Eric, yeah that is my idea too. The more people we can get out there the better and the faster we can all go without spending crazy $ the better too. I'm working on some other ideas that I'll be testing out this season. I'm a designer by trade so for me it's all part of the fun.
I ran the single spring 5 plate setup @ the Seattle track w/ 1 Newfren carbon & 4 thinner Malossi carbon (from SIP). Initially, I had a little bit of slippage when I got on it, but it felt like it was hangin on a bit better the more we rode. Maybe they need to get hot first? I might give the XL2 another chance, but I like the idea of more mating surface on the single spring. Now if I can just squeeze a little more juice out of this motor.... ;D ;D
it is worth noting here that if any of you want to run the xl2 clutch in a standard primary you will likely need to modify it to fit. the clutch spider is deeper and could rub on your primary basket. grinding, machining, or spacing could be necessary. might not be an issue if you removed springs and such to weld up your primary. you could also spring for the DRT basket. I would just like to say... damn you smallframe clutch. damn you.
I have some clutch info as well, caveat emptor and whatnot.
Built up a clutch with the stepped out DRT PV/ET3 style plate last night. With a stock primary basket, the outermost friction plate tabs are too far out of the basket slots to be bent, as we see on other clutches. Had to go back to the standard craptastic pressed steel outer and 4 plates. Yay? No...
The SIP description says you must play with plate thickness, but doesn't mention why. After my experience last night, I can say that they are most likely referring to optimizing the disengage point. Normal cork and steel plates would almost certainly bind this configuration. With my carbon plates, spacing is just about right with 5 plates. If only it fit in the primary basket!
One last thing: In order to save a few $$ I also bought the cheaper DRT outer plate (different than the aboveplate). The one received was crap! I contacted DRT and they don't manufacture this part. They act as a distributor for Surflex, and the Surflex outer is so distorted (conical, in the wrong direction) that is completely unusable. I wouldn't even put it in a stock bike.