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Help w/ STM Secondary

2545 Views 8 Replies 3 Participants Last post by  rvsperformance
2008 Renegade X with VFJ primary, 27" Bighorns, ride almost 100% trails in Colorado Mtns.
Looking to order an STM secondary and am having trouble choosing the proper helix. Anyone have a similar setup with a good working helix choice and amount of shims.

And if anyone is wondering, the VFJ completely transformed my 800, pulls my brothers 1000 and buddies 1000 Scrambler by a length or two off the start then they SLOWLY begin catching up.

Any help is appreciated, thanks.
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I think we went with the pink spring for 26 inch and trail riding. BrianE tried 4 or 5 springs and I waited to buy my stm until we tuned his. I will be talking to him tonight and will confirm. Ours are 11 and 10 800s.
We've sold a few of them to guys with the VFJ and set them up the same as we do for the QSC primary. No complaints on them.
What helix selection would be a good choice? The spring I'm not so worried about
There's the problem. I don't comprehend along with many others what the benefit of running a straight 40 would be vs a 50/40 with say a pink or gold spring. If someone could explain that would be most beneficial. I think I have read every post about tuning secondaries and actually gained more confusion and frustration than knowledge.
The size of tires you run, performance mods, type of riding you do, and what primary you run all has an effect on what spring and helix you install. I know the QSC setup well, but it's also tuned for the aggressive profile of the QSC weights compared to the others out there. To steep of a start angle will bog the machine down off the line. To shallow and you leave a lot of pull on the table. The spring controls how fast it shifts down the ramp angle and how fast it backshifts.

Truthfully it's a combination of black magic and voodoo that some of us have sold our souls to understand.
Well if you make a recommendation I might have to give you a call.!.!.!.
It's hard to recommend a setup for someone else's primary. The QSC silver secondary spring and 40 helix has been working good in the ones we've sent out running the VFJ primary. But that isn't to say there isn't a better setup. Most riders wouldn't know if it was the best setup or not. The VFJ and QSC primary clutches are so close in design that it's not even a concern. The weights and spring rates used in them are entirely different though. That's what makes it hard. But we would set you up using the QSC formula based on the fact you have the VFJ primary, and what tires, elevation, and performance mods you have done. If it isn't exactly right you'd be able to adjust the weights in the primary to tweek it a little to be right on.
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