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First ride with P-85'd 800R

Thanks for the feedback. I have checked the crank and it's .002" at the center of the taper. I also checked the center shaft of the clutch while on the crank and got .0055". I would say this is pretty good. I will keep you posted on how it does after rebalancing.

On my 98 Summit X I had a P-85 with an AC secondary and I put 5000 miles on that sled with n engine issues. Never had to do anything to the primary and I probably had about 3500-4000 miles on that clutch.

I put a P-85 on my 01 700 Summit when I got it and I would break the primary spring in about 20 miles into the ride. It did this 3 times before I finaly put the TRA back on.

Now I have about 4000 miles on the Summit 700 without any engine problems, but it just didnt like the P-85.
 
I have a couple of 670's with the p-85; one does good the other one keeps throwing off the dampner on the flywheel. I'm not sure but I think they balance the motor with the tra on and match it with different weight harmonic balancers on the flywheel. I've been wanting to weight each dampner to see what the weights are but haven't got around to it yet. I'm building another 670 to put in a light weight chassis and will for sure do it then. I'm curious to see if the dampner weighs the same as a tra. If it does maybe I'll build a dampner to match the p-85. It's something to think about. Does anyone know for sure about this?
 
Got the clutch spin balanced, it was very close but now it's good.
I also found that backing off the engine torque stop about 1/2 a turn did ALOT for reducing vibration! It was just too tight and transfered too much vib.
I am really liking the P-85 now, I didn't have the primary spring today that I really need to use but had one that was close. Was down slightly on RPM and it will now pull from the sleds that ran even with the TRA. I see almost exactly the same RPM on a steep hill as I do on the flats.
I found it likes a shallower helix, I had a 44/40 but the 44/36 works better and brought the belt temps down even more. Even with the shallower helix it still pulls HARD at higher speeds.
I have been using the Doo roller secondary and now have a Team to play with, if it gets any better that it already is I won't know what to do!! Also using the -166 white letter belt. 10-64's, 44/36, ran a 120/310 and want to try a 120/340. Still playing with gearing also.
If you are fighting your TRA this is a good option.
 
Running 800r motor in a lynx almond red spring 66g spi weights 66/44 helix black secondary spring 155-222 revs 8400 with rktek head and pistons and crankshop twins.
 
Did 35 miles and tried a few settups today. MUCH more consistent then the TRA....8200 on the flats, 8200 on a climb, better backshift even using a steeper helix in the stock Doo roller. Not completely dialed in yet, but looking promising. Will play more with gearing and trying in different snow conditions.
I was surprised that it still hits as hard as the TRA off the bottom, even with taller gearing. Seemed to pull good in the mid and I havn't had a chance to pull past about 60mph yet. Will play with it more tomorrow.
It does drop 6 lbs off the sled too!!
I liked the TRA when it was "right" but until they figure out how to keep rollers and bushings in them I will run this.
Winter Brew,
I sent you a PM.
 
Got the clutch spin balanced, it was very close but now it's good.
I also found that backing off the engine torque stop about 1/2 a turn did ALOT for reducing vibration! It was just too tight and transfered too much vib.
I am really liking the P-85 now, I didn't have the primary spring today that I really need to use but had one that was close. Was down slightly on RPM and it will now pull from the sleds that ran even with the TRA. I see almost exactly the same RPM on a steep hill as I do on the flats.
I found it likes a shallower helix, I had a 44/40 but the 44/36 works better and brought the belt temps down even more. Even with the shallower helix it still pulls HARD at higher speeds.
I have been using the Doo roller secondary and now have a Team to play with, if it gets any better that it already is I won't know what to do!! Also using the -166 white letter belt. 10-64's, 44/36, ran a 120/310 and want to try a 120/340. Still playing with gearing also.
If you are fighting your TRA this is a good option.


Sounds great...The poos work great with a 36 finnish also...I would say your purty close...BJ
 
Clutching works great, engine blew up :eek: Hopefully just a coincidence, sled is stuck in the mountains, don't know the cause but do know the PTO side burned down....stock engine, stock jetting, MAG side looked fine.
Best so far is a 120/340, 10-64's, Team w/58/42.46, red/pink, 19/45 gears. Might need to go with slightly less helix, 58/40.46 perhaps. 47-50mph on a climb in the deep.
 
I too run the p-85 on my 07, i have over 500 miles now with the p-85. A total of 1600 miles on original crank. I lost compression 200 miles ago, doo replaced top end on warranty and crank inspected as new. Im not worried about the p-85 throwing the crank out. The damage would have showed when inspected. The p-85 rocks with dj`s helix. TRA`s suck.
 
good luck getting it out brew, have you thought about putting a starter ring on the p85 also take the edges off the spider nut as during spring wobble they can break the spring. Thanks for all the testing and who is willing to cut the taper and spend the time to do it right. Also I find that the .46 is almost always too much so adding one slp shim which brings it to .40 or two which brings it to .36 but adding the shims is a cheap easy way to get dialed on helix without spending 100 bucks a pop. Let us know when she is out of horse corral.
 
I too run the p-85 on my 07, i have over 500 miles now with the p-85. A total of 1600 miles on original crank. I lost compression 200 miles ago, doo replaced top end on warranty and crank inspected as new. Im not worried about the p-85 throwing the crank out. The damage would have showed when inspected. The p-85 rocks with dj`s helix. TRA`s suck.


What set up are you running and what altitude do you ride. I am going to try a p-85 on a 08 146" Summit. I ride mainly 3000' to 6000'

Thanks
 
What set up are you running and what altitude do you ride. I am going to try a p-85 on a 08 146" Summit. I ride mainly 3000' to 6000'

Thanks

Polaris 120/340 primary spring..(black green)
55 gr. adjustable heavy hitter weights. 66 gr. at 7000 feet.
doo secondary factory spring, 44/36 helix.
I will be trying the dj helix next week. The dj helix works well at home, just need to tune for the hill now.
 
Clutching works great, engine blew up :eek: Hopefully just a coincidence, sled is stuck in the mountains, don't know the cause but do know the PTO side burned down....stock engine, stock jetting, MAG side looked fine.
Best so far is a 120/340, 10-64's, Team w/58/42.46, red/pink, 19/45 gears. Might need to go with slightly less helix, 58/40.46 perhaps. 47-50mph on a climb in the deep.

Winter Brew,
When you put the P85 on with the stock doo secondary did you have any alignment issues ?
 
Winter Brew,
When you put the P85 on with the stock doo secondary did you have any alignment issues ?

I had to add 2 shime behind the secondary....but they may vary with the amount of material removed when the taper is machined.
 
Winterbrew I know that supreme tool makes a billet off set face clutch cover and spring cup so that you can run a tra spring i a p 85 just wondering if this may help with the spring breakage problem. please keep us posted on the progress Rodger
 
I had to add 2 shime behind the secondary....but they may vary with the amount of material removed when the taper is machined.

The reason I ask is i am going to try and put a P85 on a XP and was wondering if i would have alignment issues with the P85 ?
 
The reason I ask is i am going to try and put a P85 on a XP and was wondering if i would have alignment issues with the P85 ?

Like I posted on Dootalk, the P-85 will NOT work unless you use an aftermarket jackshaft so you can shim the secondary or float it. The 07 were NOT fixed like the 08's are so the process is much easier.

The P-85 does scare me though because it is so much lighter than the TRA is.

Winter Brew, did you remove the counterweight from the flywheel whan you installed the P-85 or did you just run it the way it is?

The P-85 is a great clutch as long as the crank holds up in the R engine.


-Seeder
 
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