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Riiiiiide...
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Discussion Starter · #1 ·
Came across a thread over on ridemonkey, and didn't find much info about the topic here on mtbr, only the DU bearing system, so...

http://www.ridemonkey.com/forums/showthread.php?t=219863&highlight=corsair

Seems people can tell a difference with these kits. Someone mentioned the bearing turning 15 degrees just by sitting on the bike (hacktastic on the last page.. diy version). Obviously it's counteracting the binding effect. I'm even thinking that this is similar to what people supposedly feel when they change over to a Ti coil.. the Ti has much less material so binding is felt less .. ??

Anyways, i think i'm going over to the bearing shop this week to find something suitable and make it myself, but only one between the coil and preload collar.

Your opinions? Anyone tried it?
 

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If you read the RM thread, you have seen my comments, but I will repeat some here.

I am running only the bearings and races/washers as Jim did not have the proper housing for my shock/spring when we were playing with them. Not sure how long they will last being open like they are with the wet weather, but they have been on since Cworks and are still working.

Because I was with Jim for 3 days durring crankworks and he had a bunch of springs, bearings, and other parts, I was able to do some back to back 'testing' (with a bike I have ridden for two seasons, so I am very familiar with it) with several configurations. In the end, I stayed with my original spring rate, and added the bearings on a the shock.

For me, the bearings did make a noticable difference. Not HUGE, but definately noticable. The rear just seemed a little more free and easier to move. More supple. I noticed no difference in dynamic ride height or bottom out resistance...nor did I change spring rates (tried 25 and 50 lbs higher both with and without the bearings) but it just felt like the bike was able to more readily able to suck up smaller to mid sized imputs especially in the upper part of the travel.
 

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Riiiiiide...
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Discussion Starter · #6 ·
mx_599 said:
it would be interesting to see bright reference marks on collars and bearings and someone rig a video aiming at shock and then take a quick spin on bike
Hm, even better, a double blind test, or even a quadruple blind test. One bike, 4 shock/spring setups, all with the EXACT spring rate. 1- normal steel coil. 2- normal steel coil with thrust bearing. 3- Ti coil. 4- Ti coil with bearing. And this with as many experienced bikers as possible, with the shock covered so that the spring setup cannot be seen.

But like i said, on RM someone mentioned that he saw 15 degrees rotation on the bearing.. if that's true, it should be proof enough. But a double test would be the real thing. Only thing is, don't expect a 'manufacturer' to do it. It would have to be several independent riders with plenty of shock tuning experience to have any validity.

All in all, i see this only having noticeable effect at lower speeds and/or low speed compression (as Davep mentions). And if that IS the case, the normal binding effect at 'low' speeds might even be a plus on some bikes.

:madman: Damn this suspension mumbo jumbo!! Well, somebody's got to be the guinea pig.
 

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PsyCro said:
Hm, even better, a double blind test, or even a quadruple blind test. One bike, 4 shock/spring setups, all with the EXACT spring rate. 1- normal steel coil. 2- normal steel coil with thrust bearing. 3- Ti coil. 4- Ti coil with bearing. And this with as many experienced bikers as possible, with the shock covered so that the spring setup cannot be seen.

But like i said, on RM someone mentioned that he saw 15 degrees rotation on the bearing.. if that's true, it should be proof enough. But a double test would be the real thing. Only thing is, don't expect a 'manufacturer' to do it. It would have to be several independent riders with plenty of shock tuning experience to have any validity.

All in all, i see this only having noticeable effect at lower speeds and/or low speed compression (as Davep mentions). And if that IS the case, the normal binding effect at 'low' speeds might even be a plus on some bikes.

:madman: Damn this suspension mumbo jumbo!! Well, somebody's got to be the guinea pig.
but didnt he say he saw that with sag only?

i thought it would be neat to see it on a video clip going through the range of travel
 

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In my view the so called "binding" of the coil from rotating in standard perches causes the coil to flex wider while compressing as part of the spring resistance. Its not really binding since the spring can grow wider without restriction. Remove that rotational restriction with the roller perch bearings and the same spring is softer, and perhaps slightly less progressive, more linear.

It would be interesting to see dyno figures on the softening and rate change effects of the rolling perch plates
 

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Riiiiiide...
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Discussion Starter · #11 ·
Well, it's done. I put a set on my Maelstrom and a friend on his Prophet. I won't post pics as they're cell phone pics and don't look that great.. and the link above by Tmpaints has pics anyways, of the exact same thing.

On my bike, i can see a mark on the coil, at the top end, rotate about 3mm when i sit on the bike. On the Prophet we can't see it move because its a much smaller shock so its not as visible at sag. My friend is pretty happy with the difference in feel, and just by pushing down on the seat i can feel the shock working a bit different than before. I would describe it as less stiction/friction.

On my bike its the same thing in feel, although i'm not as enthusiastic about it as my friend. I'm sure that on bigger bikes with more and/or better suspension its harder to tell because the suspension works great as it is.

All in all, if this is the same difference that people notice when switching from steel to Ti coil, then this is a worthy upgrade and very cheap.. definitely cheaper than a Ti coil!
Cleaning the bearing every now and then is as easy as loosening the preload collar and wiping it down. The only problem is that the lip on the preload collar now centers the bearing instead of the coil, so its necessary to fit something or other to fix that. Hopefully i find an easy fix soon.
 

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make a custom spacer from pipe

PsyCro said:
All in all, if this is the same difference that people notice when switching from steel to Ti coil, then this is a worthy upgrade and very cheap.. definitely cheaper than a Ti coil!
Cleaning the bearing every now and then is as easy as loosening the preload collar and wiping it down. The only problem is that the lip on the preload collar now centers the bearing instead of the coil, so its necessary to fit something or other to fix that. Hopefully i find an easy fix soon.
A bit crude, but should work.

Match the shock barrel OD and the spring ID to the appropriate pipe specification.
Buy it by the foot, cut it to length. Hold it in place with a tie wrap beneath the pipe spacer.
Follow the link for tubes.

http://www.mcmaster.com/#plastics/=5ouffd
 

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just had a discussion with my mx friends regarding thrust bearings.. he have bluntly stated that they wun work n mx folks have used it and scraped it .... but a few chaps that bought the mcmaster DIY kits, said bump chattering reduced, smoother end stroke etc..

has anyone done a nice delrin diy housing for the bearings outside of what obtainium has?
 

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The only difference it will make is a slight reduction in spring rate. If you let one end of the spring rotate freely as it compresses then it's slightly less force to compress the spring the same amount.

IMO it's a fiddly way to reduce your spring rate.
 

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Dougal said:
The only difference it will make is a slight reduction in spring rate. If you let one end of the spring rotate freely as it compresses then it's slightly less force to compress the spring the same amount.

IMO it's a fiddly way to reduce your spring rate.
thanks for the reply. sorry was out for the weekend. didnt bring any comp with me.
will it make a difference in that sense for high leverage bikes? where, on the end stroke, coil binding would be reduced?
 

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Jhanney said:
thanks for the reply. sorry was out for the weekend. didnt bring any comp with me.
will it make a difference in that sense for high leverage bikes? where, on the end stroke, coil binding would be reduced?
It won't make any difference to coil binding, that only happens when your spring is too short for your shock.
These thrust washers will make a bigger difference on springs with fewer coils, like the titanium ones in the pictures. Seems like the expensive springs have created a market for another expensive product.
 

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Dougal said:
It won't make any difference to coil binding, that only happens when your spring is too short for your shock.
These thrust washers will make a bigger difference on springs with fewer coils, like the titanium ones in the pictures. Seems like the expensive springs have created a market for another expensive product.
understood. sounds like the needle bearing to the DU bushing is a better option overall
 

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Riiiiiide...
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Discussion Starter · #19 ·
fwiw...

This should be interesting for you all..

On my 2:1 leverage ratio Maelstrom using a 190lb coil, i get 32% sag. With one of these bearings above the coil i get 36% sag. With a bearing above AND below i get 40% sag.

So yeah, it effectively just gives you a softer spring.
 
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