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Rear race clutch for big stroker motor

Posted: Wed Apr 29, 2015 3:00 am
by Spooneg6
What would be the best rear clutch for my 125cc stroker? I want very aggresive take off . I was looking at the polini rear clutch but the stage 6 looks like it has more settings. Also besides those egay springs are there any clutch springs stiffer then 2k rpms? And a stiffer center spring then 2k rpm? Comments would certanly be apreciated . Also will be runing light weights in vari . 125cc stroker with PG big stroker pipe my set up all in a nut shell

Re: Rear race clutch for big stroker motor

Posted: Wed Apr 29, 2015 10:21 am
by 1man8scoots
2 shoe polini is great for drag racing large torque engines.

Re: Rear race clutch for big stroker motor

Posted: Thu Apr 30, 2015 2:13 am
by Spooneg6
Are the 2 shoe clutches adjustable ? As in can i set it at over 2k rpm stall? Btw graphit i messaged you a while back

Re: Rear race clutch for big stroker motor

Posted: Thu Apr 30, 2015 7:51 am
by Wheelman-111
Greetings:

With two sets of return springs and a threaded tensioner, the 2-shoe can be set to engage at over 5000-6000RPM if needed. That kind of stall speed can be very rough on all the hardware behind the clutch however. The stuff wasn't really designed to handle big torque.

Re: Rear race clutch for big stroker motor

Posted: Thu Apr 30, 2015 11:58 am
by DirtyE
Here's a little knowledge I just learned. Higher clutch grab rpm doesnt equal better take off. Correct me if im wrong, but you want the clutch to grab right as or just before the rear pulley opens. I had my polini 3g set at too high of an rpm and the belt was already down in the pulleys by like 10mm as the wheel started to move. I lost all of that variation until I backed out the spring tension. Im assuming here that your 125cc won't be a super high rev machine but I could be wrong about that.
So your going to want to find which rollers set your rpms in the powerband, find a suitable torque spring then adjust your clutch from there.
After buying several clutches from various manufacturers, I've come to the conclusion (personally) that a lot of the "fine tuning" adjustments are really sort of unneccesary and can sometimes just add to confusion of an already confusing enough process of scooter tuning.

Re: Rear race clutch for big stroker motor

Posted: Thu Apr 30, 2015 4:23 pm
by Wheelman-111
Greetings:

You want the clutch to grab WAY before the variator starts a-squeezin' the belt. "Low gear" for the first few yards at least. A very high-revving engine set-up will have comparatively light rollers and/or a very strong Contra spring so the belt doesn't even begin to move until the engine is in the foothills of its power band. If the engine makes torque down lower, the clutch and belt both need to be adjusted to that lower RPM, but the clutch must still bite before the belt moves.

Re: Rear race clutch for big stroker motor

Posted: Thu Apr 30, 2015 9:37 pm
by DirtyE
Is there a set Rpm per say for clutch bite before belt drop? I would think you want it near simultaneous if not just before the belt drops.... if you rollers and springs are set proper then you'd want your clutch to engage so the variation can begin cause your at the desired rpm.

What's the guy with the dyno (g9) say about this? Hey G, you've got to work those trannys to get nice curves, what's the dillio?

Re: Rear race clutch for big stroker motor

Posted: Thu Apr 30, 2015 10:04 pm
by Rip_City_Spree
He might be off the air for a bit. Not sure when he said he was gonna closed

Re: Rear race clutch for big stroker motor

Posted: Sat May 02, 2015 6:37 pm
by maddog
The best clutch for full strokers is a stock Honda clutch, I have tested all of the aftermarket ones which slip & slide but the stock Honda clutch grabs & bites off the line with an 86/87 stock bell, the stage-6 clutch is only good for smaller scoots.

Re: Rear race clutch for big stroker motor

Posted: Sat May 02, 2015 10:17 pm
by 1man8scoots
I just got back from a ride with my fabrizi and the 2 shoe, it grabs perfect. It's set up a little high on the stall but I'm running 6.98:1 gears so it needs it. I'll be comparing it to my 3 shoe and delta in the next few days if it's nice out but I feel secure that the 2 shoe is awesome.
Also mad dog is a moron, the stock clutch will melt with the stroker.

Re: Rear race clutch for big stroker motor

Posted: Sat May 02, 2015 10:36 pm
by 1man8scoots
I'm attempting to upload a video of the break in run, half thottle forces it into 10.5k and it grips great. I'm running malossi 16/32 primary gears with a pirelli diablo 130/70-12 so this clutch is taking some abuse from a dead stop. I can't wait to open her up.

Re: Rear race clutch for big stroker motor

Posted: Sat May 02, 2015 10:42 pm
by curtis966
1man8scoots wrote:I'm attempting to upload a video of the break in run, half thottle forces it into 10.5k and it grips great. I'm running malossi 16/32 primary gears with a pirelli diablo 130/70-12 so this clutch is taking some abuse from a dead stop. I can't wait to open her up.
Sounds sweet! I have a polini 2 shoe on my mini stroker havnt tested it out quite yet but figured it would be a good clutch for my set up.

Re: Rear race clutch for big stroker motor

Posted: Sat May 02, 2015 11:18 pm
by 1man8scoots
Here's a link to the first break in run after all the heat cycles. I'm going to change the clutch to finish the break in so I'm not launching at 8500 rpm.
http://vid1380.photobucket.com/albums/a ... owthjg.mp4

Re: Rear race clutch for big stroker motor

Posted: Sun May 03, 2015 10:00 am
by DirtyE
Better get some gas in there too!

Re: Rear race clutch for big stroker motor

Posted: Mon May 04, 2015 8:09 pm
by Spooneg6
I mean i want a nice stall , but i feel that video that was posted was just burning up the clutch shoes lol