Excede the max rpm on your drive clutch, and you will get to experence an IED without going to Iraq.My son and I were standing right next to it when I bliped the throttle on my 50 horse. It exploded!! I can't believe neither of us got hit by anything. We never did find all the parts. Be carfull!
Whipper
I now run steel guards over all my clutches. I'll be working on Bridget's Max SS guard this week.
Whipper
Aw, James, just fire it up and go. If you want more, do the torque converter spring change. Don't go over.. what.. 35 mph or so on the top end. hehe
Whipper bought an aftermarket clutch for his briggs/attex
To Invent, you need a good imagination and a pile of junk. (Thomas Edison)
Whipper, what make and model of drive clutch do use to handle the high rpm's? I have been looking at Comet industries web site, but they don't give a maximum rpm range.
Will the driven clutch be o.k. with the red spring?
You can calibrate a Comet 102C quite easily, but I'm not sure the weight and spring combos will work with a 4-stroke application. Always remember that the driven clutch can be more deadly, especially since when the engine on a two stroke is cranking at 6000 rpm, the driven clutch is moving quite a bit faster. I honestly don't know how these things hold up. I run 3/16" thick steel for guards on both racers. I still get squeamish.
~m
Mike, I dont have mcuh experience with experimenting with clutches, but I have heard that the 102C Comet it quite popular among snowmobile racers just for the reason you mentioned, its ease to adjust/calibrate. The 102C is a pretty big clutch so make sure you have enough clearance between your engine shaft and tub. Also, I believe that the 102C along with most snowmobile 2 stroke clutches, it is only for a tapered shaft. Every Max model comes with a keyed shaft. Just something else to keep in mind. And as far as the guard that you have on the racer to prevent any potentially dangerous situations with your clutch system, I think that is a very good idea and Im not too sure if I feel that safe with that flimsy Ski-Doo guard that Im using on my racer......3/16" steel sounds much better.
"Looks like you have a problem with your 4 wheeler........you're missin' two wheels there"
I spoke with Don Jackson at Comet Industries today. He suggested the 94c duster torque converter and the 90d driven clutch. He told me the 94c is good to 8500 rpm and is available for a 1" shaft. I think I have my torque converter issue solved.
If $ is a factor, the stock clutches will be fine, unless you run it out on top end a long way. Otherwise a nice, adjustable, safe unit would be great to let the engine rev a little.
Your II is a lot lighter than my 8, but neither of us will be seeing the kind of rpm that George and company turn. Their vehicles are much lighter and less rolling resistance, and our engines aren't putting out what theirs are. And with a cvt, the engine rpm is locked to one speed. Like mine was at about <3500 or so. Getting it up about another 500-1000 will take advantage of the broader power curve. Mine runs between 3 and 4000 most of the time. Topped out on level ground, it's never seen over 6000.
Also, I guess you're doing the 2 steel pushrods, and thinning the flywheel key for advance?
To Invent, you need a good imagination and a pile of junk. (Thomas Edison)
James,
Don is a great resource; he helped me set up a Duster Drive and Driven clutch to replace the oem clutches on my hustler. I have been very happy with the set up. The driven unit has 6 different tension settings and the drive unit is easily adjustable by adding springs and weights. The only down side is that the driven unit is only available to fit a 30MM(tapered), 1" or 3/4" shaft. Buy the 3/4" and have a machine shop bore it and re-cut the 1/4" keyway to fit the 7/8" output shaft of your t-20.
eBay Motors: Comet 90D Driven Clutch 3/4" Bore, 1-3/16" 212299A NEW (item 200133929448 end time Jan-22-08 05:27:01 PST)
Comet 94C Duster Clutches
Good Luck!