soft spring

[ryan 83]

Can someone explain to me why my torque or torsion spring what ever you may call it is getting soft(weak) after about 15-20 minutes of riding or about 10 300 ft. practice runs? I have went through 3 in the last 2 weeks in only about an hour of riding time. Of course you can still ride but for drag racing we are getting about 5-6 great launches and then it starts fading off again. Have changed many different combinations now I have a drr rear clutch assembly suppose to be lighter than stock that has been drilled. Didnt really notice any change. Any help would be appreciated.

Keith

[Logan #34's Dad]

HEAT. Once a spring gets hot or up to your set-ups hottest temp., it will perform differently. I used to start the weekend with one set of rollers then once the spring has had a couple heat cycles I dropped the weight and it would last longer. Once they get hot they become more pliable or weaker. Try lowering your variator weight after a couple runs.

[EthansDad]

What he said, heat. What is causing it would be good to know. Tuning weigts to a new spring is not always the way to go. Run it once let it cool, then find the magical roller weight combo you seek.

You mention a different rear clutch that I'm guessing raised your stall speed (higher rpm before launch). If the stall is too high, it can cause excessive heat and wear that spring down faster. The adjustable rear clutches are good because you can raise/lower stall without drilling holes.

[selbygirl]

we were going through springs also. this is how I fixed that problem. it lets air get into the cvt cover.
I hope this helps you.

http://i894.photobucket.com/albums/ac143/selbygirl/th_IMGP7592.jpg (http://s894.photobucket.com/albums/ac143/selbygirl/?action=view&current=IMGP7592.jpg)


[IMG]http://i894.photobucket.com/albums/ac143/selbygirl/th_IMGP7597.jpg (http://s894.photobucket.com/albums/ac143/selbygirl/?action=view&current=IMGP7597.jpg)

[#404's Dad]

Originally posted by selbygirl
we were going through springs also. this is how I fixed that problem. it lets air get into the cvt cover.
I hope this helps you.

http://i894.photobucket.com/albums/ac143/selbygirl/th_IMGP7592.jpg (http://s894.photobucket.com/albums/ac143/selbygirl/?action=view&current=IMGP7592.jpg)


[IMG]http://i894.photobucket.com/albums/ac143/selbygirl/th_IMGP7597.jpg (http://s894.photobucket.com/albums/ac143/selbygirl/?action=view&current=IMGP7597.jpg)

Is that the Intake or Exhaust for the Air ?

[selbygirl]

this would be exhaust to let the heat out.
then I made a vent tube for where the starter goes to let more air out.

http://i894.photobucket.com/albums/ac143/selbygirl/IMG_0803.jpg

http://i894.photobucket.com/albums/ac143/selbygirl/IMG_0783.jpg



then I had to go with an over-range system with a 90 cover. I put the tube up front and back to let air come in and out with a removeable cover.

http://i894.photobucket.com/albums/ac143/selbygirl/IMGP9991.jpg

[fomospede]

mine is also vented but the ones on the polaris predators look pretty good for an off the shelf!

[ryan 83]

Thanks to all for the info. Keith

[skyeryder]

We had a similar prob like everyone else already stated, but we also had a clutch hub(sheeve) whatever you want to call it that was out of round(bent) after I replaced it we didn't have anymore problems

[selbygirl]

bump

[farmboyquad]

I was dealing with some what of the same problem. Then I found out that some of the springs I was starting with were softer then marked in the box to begin with. I bought a spring testing tool that I saw at https://www.youtube.com/watch?v=mSR04OjP6fU you can get them at www.recmotor.com