Help with STM Clutches !

[boostedballz]

Running a Rage 8 primary w STM Billet secondary on our race Apex. I am looking for anyone else s set up. I am running 85ish grams in the main arms small rollers in the secondary arms. Have a straight 52 degree roller AC helix with Green AC secondary spring wound lots. I all of a sudden have an issue with slippage and over revving. I added 5 gr of weight and the problem got worse. I can't possibly be slipping the secondary as its a 3 man job to change a belt in the thing. Any similar set ups would be appreciated.

LL

 

[gunnerthesnowman]

Running a Rage 8 primary w STM Billet secondary on our race Apex. I am looking for anyone else s set up. I am running 85ish grams in the main arms small rollers in the secondary arms. Have a straight 52 degree roller AC helix with Green AC secondary spring wound lots. I all of a sudden have an issue with slippage and over revving. I added 5 gr of weight and the problem got worse. I can't possibly be slipping the secondary as its a 3 man job to change a belt in the thing. Any similar set ups would be appreciated.

LL

What kind of boost/HP are you running .

 

[boostedballz]

MCX Race kit. 22 psi rated at 450 hp

 

[gunnerthesnowman]

MCX Race kit. 22 psi rated at 450 hp

With that kind of Hp i could see it slipping in the secondary with a 52 degree straight cut helix , the rage 8 works nice once it is set up right , i got one with my OSP engine/turbo set up , and Jim know how to set them up , if you PM me i phone # i will call you.

 

[zebiraross]

Are you running the stm weights? If so are they the x series and where are they loaded?

 

[boostedballz]

Running the Supertips 72 x Weights. Was running the STM notched 68's but busted one and borrowed a buddies 72 gram Supers and found the sled had a harder more consistent shift. Was also a little gun shy after seeing the stm weight whip past me at 10,000 + rpm . Washers are in the center and tip.

LL

 

[zebiraross]

I never had any luck with the x series weights, imo they are way to aggressive. If you load them in the heel belts blow like crazy, if you load them with tungstens in the tip like they need the clutch literally wont shift out. once I switched over to the standard 60g base weights I didn't have any more problems.

 

[1500psi]

Ttt

Running a Rage 8 primary w STM Billet secondary on our race Apex. I am looking for anyone else s set up. I am running 85ish grams in the main arms small rollers in the secondary arms. Have a straight 52 degree roller AC helix with Green AC secondary spring wound lots. I all of a sudden have an issue with slippage and over revving. I added 5 gr of weight and the problem got worse. I can't possibly be slipping the secondary as its a 3 man job to change a belt in the thing. Any similar set ups would be appreciated.

LL

What else do you have for secondary parts?

 

[gus bohne]

The best thing to try so far,,

Remove the STM driven and install your stock unit or a STD cast oem bearcat driven.
A customer has the STM clutchs on his race rx turbo, I spent 3 days trying to get it consistent, Swapped out drivens and all the issues went away in 2 runs.

The driven doesn't hold the belt .. several of the fast guys on Ice did the same too..

When we swapped to the stocker cat, we dropped to a red white cat spring too, when we tried that same set up in the stm it just popped the belt on launch BOOM! too much pressure needed to grip.

Look at some of the popular yams and you will see a cast cover on the back clutch ???? dead give away..


We did have the STM working well if we let the track spin on the starts .. but that aint how you win races..

they are strong drive clutchs and I too LOVE the X weights for the turbos on ICE.

Gus