Clutching the 503 (Questions) and what not to do.

[ozzydog]

What not to do with a p-85

I (Harley) am running a p-85 on my 503 with an Artic Cat secodary. I put the secondary on before the p-85. I loved it and it is the real ticket to gains when it comes to a 503.
I now have the p-85 on, went riding today, not much snow but enough to tune.
Oh, I put a tunder shift kit in my p-85 also.
First I had in the red polaris spring, dont do there, too much tension. I now have the dark blue with white polaris spring in, 120lbs on the engagement and 310 lbs on the shift tension.
She kicks in nice at 2700rpm.
She is ok off the get go, but then due to a weight issue on the arms, she bogs down in even a foot of snow, no power on the mid range or top end.

Now question for you all am I running too much weight in the middle of the arms or not enough, should I have more weight on the outers??
I am running 6.6 grams in hole #1 (close in), 3 grams midrange, and .9g on the outers.
My arm weighs 37.6 g and and the total weight is 10.5 g for a total of 48.1g total for the arm plus the weights.

What are you guys running for weight on your arms for total weight? And what springs are you using, please give Engagment pretension and Shift tension on the spring as there are so many colors out there for each make.

For you guys with 600's give me a spring and a weight you are using, at least I will have a baseline.

Thanks,
PM me or post here.

 

[RudeAwakening]

310 lbs on the shift tension! wow, im new to clutching but that seems very high for a 503. i think you would want to be around 180 to 210. some one else will have to comfirm.

 

[cjgodden]

A polaris red is a 120/245 and a dark blue/white is 120/310. If any thing increasing the final spring pressure should stop the upshift not make it upshift faster.

Does it run good on the hard packed?

 

[cjgodden]

What not to do with a p-85

I (Harley) am running a p-85 on my 503 with an Artic Cat secodary. I put the secondary on before the p-85. I loved it and it is the real ticket to gains when it comes to a 503.
I now have the p-85 on, went riding today, not much snow but enough to tune.
Oh, I put a tunder shift kit in my p-85 also.
First I had in the red polaris spring, dont do there, too much tension. I now have the dark blue with white polaris spring in, 120lbs on the engagement and 310 lbs on the shift tension.
She kicks in nice at 2700rpm.
She is ok off the get go, but then due to a weight issue on the arms, she bogs down in even a foot of snow, no power on the mid range or top end.

Now question for you all am I running too much weight in the middle of the arms or not enough, should I have more weight on the outers??
I am running 6.6 grams in hole #1 (close in), 3 grams midrange, and .9g on the outers.
My arm weighs 37.6 g and and the total weight is 10.5 g for a total of 48.1g total for the arm plus the weights.

What are you guys running for weight on your arms for total weight? And what springs are you using, please give Engagment pretension and Shift tension on the spring as there are so many colors out there for each make.

For you guys with 600's give me a spring and a weight you are using, at least I will have a baseline.

Thanks,
PM me or post here.

If the red spring was too much tension why go to a spring with more?

 

[RudeAwakening]

may want something that starts at 135 or 140 to get your ingagment at 3400rpm

 

[TLKDPROD]

I'm not a P-85 expert of anykind here but I'm assuming you're holding the shift too much with a 310 pound finish spring AND probably not enough weight at the end of your arms. The fact that you're engaging that low too might be part of the problem as well. Let's say you engage at 2700 (how many horses a 503 has at 2700, I don't know, probably in the mid 30s (just a guess here), well, in order for the motor to reach 66-6800 RPM, where power begins, it has to start from 2700 then build up RPM AS it spins the track. Quite a bit more work than holding the engagement to around 38-3900. Stiffer start and softer finish would probably be the way to go I think. Sure enough there isn't that much spring to pick for a P-85 !!! Got a TRA list and there is over 70 different springs for it. P-85, about 20 !

I'd suggest to give a try to the Goodwin Performance Lime (165 - 275)
Or Polaris Almond Gold (150-290)
(http://www.goodwinperformance.com/polarisclutches.asp)

BUT before buying a different spring, Try a more even distribution of weight on your arms (as if they were normal arms). Considering the setup you have, going with lighter weights on the inside will have you to engage later (due to the fact that a lighter weight will create less inertia/pressure so in order to create that "X" amount of load to overcome the 120 pound spring force, it has to spin faster, result is a higher engagement point of course... similar to a stiffer spring) and going with a little more weight at the middle and end of the arm will more than likely create more "side pressure / belt pinch" through the shift and might over come that 310 pound finish spring a little better throughout the shift. That, is if you have enough HP to spin that much weight but I think you do. If you can't reach your target RPM, go lighter.

If I were you, I'd try them all the same weight and work from that point. If you want to create more belt pressure in the mid shift or top shift, add weight where you want. That's what a Thunder shift kit is all about actually.

Try this out and let us know if it's better. It will have to be better, everything makes sense. Hope I made everything clear enough for everybody to understand !

 

[ozzydog]

Spring tension (not a Polaris)

Ok, guys, the red spring I was running was not a Polaris Spring, it was a RED Spring from Thundershift. I do not know the specs but I do know that she was more of a spring than the Polaris dark blue with white stripe.
Sorry for the confusion.
That is why when I went to the Polaris Spring things got better. I called Lonn today at Thundershift. He suggested to move more weight out towards the end of my arms, so I am going to try that. Note: I am keeping the weight I have, but just changing it's position,. more weight moved from the inside hole to the outside hole, maybe up to a gram.
I will let you know how that turns out.
Harley

 

[ozzydog]

Stock Spring Tension

What is the engagment rpm of a 503 with the stock clutch??

 

[onewoodsrider]

About 3400rpm is stock i believe.

 

[TLKDPROD]

Harley what helix & spring you running in that cat sec ?

 

[ozzydog]

AC helix and spring

Thierry,
I am running the red spring with white stripe and a 45 degree helix. We tested many different springs and I cannot remember maybe 3 different helix. This was by far the best combination and I highly reccomend it for the. She pulls hard and she will climb. The guys in Montana are all running this now on their 503's.
Harley

 

[TLKDPROD]

Straight 45 makes a lot of sense for the mountains versus the stock helix which is full progressive 50-44 which is definately more of a sea-level power / trail oriented helix.

Considering most guys here in the mountains will never really get more than half the full shift (I refer to ''full shift'' as when the 1:1 ratio is reached with the primary and secondary, (the belt can't go higher in the primary and bvelt can't go deeper in the sec.) (ie: ''top possible speed'')), with the stock 28-56 gearing, in general deep snow / boonhawk riding, this means the shift in the secondary remains in the first half of the helix which would be between 50 and 47 degrees. Considering the power that the 503 has at elevation, this is a BIG A** helix angle to pull, even for the amount of load that a 121 track puts through the system ! So lowering the angle to straight 45 allows her to stay at a more targeted/comfortable load area for her power which has her to pull better, climb better...

Yours a 136 right Harley ? What spring rate is this red/white spring again ? Can't find the info anywhere...

Let us know how moving the weight to the end of the arms worked out, that's some really interesting stuff right here !

 

[ozzydog]

Red White Spring

I will try to find out the tension on the Red white spring. I dont' even know where we got it , I think it's an Artic Cat spring. As for the weight on the arms, I will post the info after I test it, and retest it. Right now there is not enough snow to warrant the short trip up the hill to try her out.

 

[ozzydog]

Dialed In

I finally had time to spend the day doing nothing but clutching.
So here goes: This is for the 503f.
Artic Cat secondary, 45 degree helix with the Artic Cat Red spring/white stripe.
Primary, P-85, with a Thunder shift kit, running a polaris dark blue spring with white stripe (tension on this spring is 120/310)

If you read this above on this tread you will know what all has gone on.

I have to say the below is the ticket if you have a 503f and are looking for a performance mod. Clutching on the 503f is the main perfomance mod and oh you can get so much when you do this.

I have had the primary apart 6 times today, going for a run, coming back to the trailer, tweaking the weights on each arm, putting it back together and then going for a run again.

The final end result is as follows.

Clutch engagment RPM: 3750

Top End RPM: 7230

Weight Hole #1 = 3.5g
Weight Hole #2 = 3.9g
Weight Hole #3 = 5.2g

Weight of Arm = 37.6g
Total Weight (Arm and Weights in each hole) = 50.10g

I experimented across the board and this is by far my best combination. I was very consistent in each run. Same hills steep spots and straightways.

It's all about getting the right weight placement on each arm that is for sure. Just a .5g weight movment from hole #2 to hole #3 makes a huge difference.

I know those that follow thru and do the above will love it.
I spent basically 2 months trying different combinations.
If you are not running an Artic Cat Secondary, don't bother going to a P-85. Go with the Artic Cat secondary as your first step, this will offer you the biggest gains up front, then if you so decide go with the P-85 and the thundershift kit. I do not reccomend the P-85 with out the Thundershift kit, you can do so much with the kit and the gains it offers are so worth it.

Harley

 

[TLKDPROD]

Vrey very very precious info you're sharing there Harley. 503 guys you gotta thank that !

Gonna do pretty much the same with mine tomorrow and sunday !

 

[buffaloHAWK]

Thanks OZZY....

your cutting into my Hawk Fest funds! off to ebay for a clutch....

 

[sledr2]

your cutting into my Hawk Fest funds! off to ebay for a clutch....

LOL...make sure you save enough for same beer!!!


Thanks for the info Harley!

 

[buffaloHAWK]

LOL...make sure you save enough for same beer!!!

im not a drinker...if i was i wouldnt be able to afford the garage full of junk(as my wife calls all my toys)

do i need another sledr2 shaft for another clutch?

 

[TLKDPROD]

What elevation were you at Harley when you did these tests and what was you jetting ?

I was too rich today and as we were going back down to the P-lot, I ended up somewhere near the "OK" range around 4000' and then, wow, most the clutching pretty much felt right on.

 

[ozzydog]

Elevation

Thierry,
I was wondering that, as far as elevation.
I am running 180 on my (PTO) side and 170 on the (MAG)side
As far as Elevation I was doing my tests at 3500 to 4000

So with that said, whats a guy to do when he goes way up in elevation, will there need to be some changes as far as clutching??

Also if I make it to Hawkfest I am wondering what I should be running as far as jetting, any ideas on each of the above.
Harley