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Who here is running tapp , cvtech, stm or a pro4 primary clutch

So far the Pro-4 has been a great clutch! The 3 arm is on my Sidewinder and the 4 arm is on Shagman's Sidewinder. The 4 arm definitely 60 foots better and has more adjustability. So far, bullet proof

Stock secondary on yours? Im gonna try the stock secondary . I probably should have ponied up a little extra for the for 4 arm but my thought was even the 3 arm will be a vast improvement over the stock Team cat clutch (my moveable cracked like others are seeing)
 

Stock secondary on yours? Im gonna try the stock secondary . I probably should have ponied up a little extra for the for 4 arm but my thought was even the 3 arm will be a vast improvement over the stock cat clutch (my moveable cracked like others are seeing)

Yes, stock secondary with our rollers and a 34/36 helix
 
They say the Apex clutch can handle up to 500hp.
Not a chance will it hold 500hp. 300-350 horse max, same as the sidewinder primary.
I don't know how much hp it will hold but that's what one of the vendors on here told me.
I bought the 911 response cover to put on my apex clutch from them.

The previous style Yamaha primary has handled up to 500 hpr. Simon's CPR RX1's and other sleds have been over 450 hpr on asphalt, ice and grass.
 
This is Rob Forstall who runs Pro Mod and Pro Outlaw with his 34 lbs. boosted Viper that runs consistent 5.00's and 5.10's in the 1/8th mile at 133mph with a stock primary setup by Thunder Products Clutching and the help of Big Jim (RIP) from OSP. Sled is way over 500 horse and almost dipping into the 7's over 150mph in the 1/4 mile. And with an 8JP belt.

Proof is here guys

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If your running five hundred I would us a TAPP, why try a apex clutch, billet
I decided to order the newly redesigned trail stm primary for our 998's.
Can't wait to get er on and start calibrating!
I will definitely post my results.
which one did you buy, which is the updated one? What did they say?
 
If your running five hundred I would us a TAPP, why try a apex clutch, billet

which one did you buy, which is the updated one? What did they say?
I am not running 500hp!!! I have the hurricane pm tunes with header!

The clutch is not on the stm site yet!!
It is redesigned for this season for our tuned 998's.
I will be working closely with Dave at Hurricane to dial in this clutch with my cat stock secondary teams clutch. Dave is going to dial his new stm with a stock yamaha secondary!
we will figure out the best set up on the new durable /high performance stm primary clutches once tested on trails

As I get more info on quality, reliability and tunability i will definitly share!!
 
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I am not running 500hp!!! I have the hurricane pm tunes with header!

The clutch is not on the stm site yet!!
It is new for this season and was designed for our tuned 998's.
I will be working closely with Dave at Hurricane to dial in this clutch with my cat stock secondary teams clutch. Dave is going to dial his new stm with a stock yamaha secondary!
we will figure out the best set up on the new durable /high performance stm primary clutches once tested

As I get more info on quality, reliability and tunability i will definitly share!!

I want one
 
Not a chance will it hold 500hp. 300-350 horse max, same as the sidewinder primary.

34 psi gets you just a hair over 400hp with a viper in the real world. That is 3.3 atmospheres, in a perfect world that would be 420 horsepower. That’s with zero turbo restrictions.
Even with huge cams and a ported head 500hp would be a big stretch.

Just keeping it real
 
Ok I’m done
 
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I’m with Phil, I would love to see a legitimate 500hp sled run the stock clutches
 
I am not running 500hp!!! I have the hurricane pm tunes with header!

The clutch is not on the stm site yet!!
It is new for this season and was designed for our tuned 998's.


I think it is on their site
STM 3 WSP FOR 4 strokes
 
34 psi gets you just a hair over 400hp with a viper in the real world. That is 3.3 atmospheres, in a perfect world that would be 420 horsepower. That’s with zero turbo restrictions.
Even with huge cams and a ported head 500hp would be a big stretch.

Just keeping it real

I know the owner of this sled personally, race with him every race and have even raced this sled in Pro Mod/Pro Outlaw. Know the engine builder and have seen the pics and videos of the dyno runs. This engine is fully modded with larger turbo.

Guessing doesn't count
 
I know the owner of this sled personally, race with him every race and have even raced this sled in Pro Mod/Pro Outlaw. Know the engine builder and have seen the pics and videos of the dyno runs. This engine is fully modded with larger turbo.

Guessing doesn't count

Don’t care who ya know. It’s about all of these over inflated claims of horsepower. It’s frankly getting to the point of ridiculous so I couldn’t keep my mouth shut, sorry.
 


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