Ramps???
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pDrive CLUTCH... DISCUSSION... TUNING, CLICKERS, FLYWEIGHTS... PHOTOS AND VIDEOS.
- Thread starter mountainhorse
- Start date
Been out 2 or 3 times with em now. Working well, more constant pull through the whole shift curve and pulls harder as well. Less noise from the clutch. Clutch temp seem to have been reduced, need more time to say if true in every situation but so far a good improvement. Pulling 90 grams at 9500-10,000 ft at the moment still taching 8000 ish.
Props to Zollinger Racing Products for producing some great CNC product.
Props to Zollinger Racing Products for producing some great CNC product.
Where did you put the weight?
Tip?
How hard is it to tune on the hill?
How did the spring look?
Thanks for info!!
In the heel, center, tip. Start with their recommendations first. Everyone most likely will be slightly different.
Got out today with the new weights in the clutch. I would have to agree with 24_7.
I am probably going to add more weight as I was pulling 8100 all day. If you add up all the parts of the stock weight, it equals a little over 79grams with the 38mm 16.7g bolt. I had 84 grams in the weights, which is what they recommended to start with.
The stock parts are deceiving on "real" weight being used. Which is part of the heat issue.
The way I see it if there is better performance and or at bare minimum reduced clutch temps with at min stock performance.
I'll deal with a slight over rev at low elevation if needed, just like some of us have done for years on Polaris, Cat, or Yamaha. Not a huge thing, especially since these ZRP weights at this point are showing great promise of true belt temp drops. Which I've tried several different setups this season.
Now I can really see if the P drive is truly as good as Doo says about it ability to maintain RPM over wider elevation changes. So far it appears good.
The way I see it if there is better performance and or at bare minimum reduced clutch temps with at min stock performance.
I'll deal with a slight over rev at low elevation if needed, just like some of us have done for years on Polaris, Cat, or Yamaha. Not a huge thing, especially since these ZRP weights at this point are showing great promise of true belt temp drops. Which I've tried several different setups this season.
Now I can really see if the P drive is truly as good as Doo says about it ability to maintain RPM over wider elevation changes. So far it appears good.
What is initial force and finishing force of the stock primary spring?
Has anyone been tracking where, on the primary sheave face, the belt is riding?
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Has anyone been tracking where, on the primary sheave face, the belt is riding?
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I heard some rumors a while back of a P85 Primary modded to fit the 850...
I've heard nothing since.
I'd like to see someone try this out and see what happens.
Heck, it weighs 3-4 lbs less than the pDrive.
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I've heard nothing since.
I'd like to see someone try this out and see what happens.
Heck, it weighs 3-4 lbs less than the pDrive.
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Lighter spring
Has anybody (Big John) tried the 150/350 Primary spring? If so how much weight are you running? I ride 5-8,000 feet most of the time and occasionally 8-10,000. I am looking for lower engagement while maintaining mid and high performance.
Has anybody (Big John) tried the 150/350 Primary spring? If so how much weight are you running? I ride 5-8,000 feet most of the time and occasionally 8-10,000. I am looking for lower engagement while maintaining mid and high performance.
I'm running a 150-300 at high and low elevation. 8k and up I'm running 17.6 grams on clicker 4. Low elevation I run 951 ramps on clicker 3 with 18.3 grams
Also running 951's at 8k plus? And what do you consider low elevation?
967's for high altitude. Low elevation for me is 2k and under
M
mtn mike on boost
Well-known member
years ago fastrax machined a p85 to run on my 800 cat.
not sure if they can match the taper on the new doo tho
Would go with a Yamaha clutch long before the Polaris -- you know it will last and way more tuneable. Pdrive will be just fine with a few tweaks anyway not sure anyone would be able to machine the flat spot that indexes the Pdrive into a existing clutch.
The clicker on a pDrive has nothing in common with the clicker on a TRA. IMO
To me... the term "Ramp" is an outdated carryover from the TRA that does not have any application to the pDrive Clutch in the 850's, IMO.... and confuses things more for the end user to understand in discussions.
Cam, flyweight, or just 'weight' IS a better description of the part.
You would actually have to change the weight to one with a different curve of the face of the weight, that contacts the roller, to do the same thing as a clicker adjustment of the TRA.
The TRA clicker actually changes the Ramp inclination.... whereas the clicker on a pDrive, the weight still pivots on the same axle location regardless of the clicker position; the pDrive weight will never change in terms of inclination, only starting point of 'throw' and will, IMO, only change engagement RPM as it can't change the max travel of the clutch or any aspect of the shift-curve.
The clicker on the pDrive only changes the "tip in" position of the weight and not the profile nor inclination of the curve in relation to the roller travel axis.
Correct me, with better info, if I'm wrong here....
As such, changing the clicker setting can only change how much of the weight is in the "centripidal stream" acting on the weight... which only changes engagement RPM. I know this is contrary to the manual... but I believe that the philosophy there too is a carryover from previous manuals.
In fact, I cannot see anywhere in the design where the clickers on the new pDrive clutch will have any similarity to the clickers on the TRA... and cannot see where they will adjust anything but 'tip-in' RPM...
As an owner of both TRA's and P85-Polaris clutches I've taken the time to understand them both...and, from the beginning of this very thread have evolved my understanding of the pDrive.
The mentality of P85/Cat tuning applies much more to this clutch than the mentality of tuning TRA's.
AS ALWAYS... I am sincerely open to any thoughtful description/info to the contrary... I love to learn about this stuff.
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To me... the term "Ramp" is an outdated carryover from the TRA that does not have any application to the pDrive Clutch in the 850's, IMO.... and confuses things more for the end user to understand in discussions.
Cam, flyweight, or just 'weight' IS a better description of the part.
You would actually have to change the weight to one with a different curve of the face of the weight, that contacts the roller, to do the same thing as a clicker adjustment of the TRA.
The TRA clicker actually changes the Ramp inclination.... whereas the clicker on a pDrive, the weight still pivots on the same axle location regardless of the clicker position; the pDrive weight will never change in terms of inclination, only starting point of 'throw' and will, IMO, only change engagement RPM as it can't change the max travel of the clutch or any aspect of the shift-curve.
The clicker on the pDrive only changes the "tip in" position of the weight and not the profile nor inclination of the curve in relation to the roller travel axis.
Correct me, with better info, if I'm wrong here....
As such, changing the clicker setting can only change how much of the weight is in the "centripidal stream" acting on the weight... which only changes engagement RPM. I know this is contrary to the manual... but I believe that the philosophy there too is a carryover from previous manuals.
In fact, I cannot see anywhere in the design where the clickers on the new pDrive clutch will have any similarity to the clickers on the TRA... and cannot see where they will adjust anything but 'tip-in' RPM...
As an owner of both TRA's and P85-Polaris clutches I've taken the time to understand them both...and, from the beginning of this very thread have evolved my understanding of the pDrive.
The mentality of P85/Cat tuning applies much more to this clutch than the mentality of tuning TRA's.
AS ALWAYS... I am sincerely open to any thoughtful description/info to the contrary... I love to learn about this stuff.
.
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Pin weight is also a different mentality in the pDrive on the 850's than the TRA
Adding weight to the pin is also very different on the pDrive than on the TRA.
In the TRA....adding pin weight only loaded the tip of the arm/roller.
The arm itself on a TRA, the arm-weight was a constant... unless you went with an aftermarket arm of different or adjustable weight of the arm itself
In the pDrive... pin weight adjustment affects overall weight of the flyweight and is placed at the heel of the weight... this has a different affect in the tuning of the clutch... which is was the reason for my comment in post #8 of this thread.... and why the ZRP weights are a very good tool for tuning this clutch in my opinion... with more certainly to come.
My proportions are a bit off as the center of pivot of the pDrive flyweight is further down from the pin centerline.
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Adding weight to the pin is also very different on the pDrive than on the TRA.
In the TRA....adding pin weight only loaded the tip of the arm/roller.
The arm itself on a TRA, the arm-weight was a constant... unless you went with an aftermarket arm of different or adjustable weight of the arm itself
In the pDrive... pin weight adjustment affects overall weight of the flyweight and is placed at the heel of the weight... this has a different affect in the tuning of the clutch... which is was the reason for my comment in post #8 of this thread.... and why the ZRP weights are a very good tool for tuning this clutch in my opinion... with more certainly to come.
My proportions are a bit off as the center of pivot of the pDrive flyweight is further down from the pin centerline.
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