# needle bearings on shock spring effectiveness?



## pablo4429 (Mar 14, 2008)

Hey all,
So I was looking on mcmaster carr and they have needle bearings and washers that will work for my Vivd. before I order them, do they actually make a noticeable difference? Ive heard that changing out the bushings on the shock for needles does a decent amount for the smoothness and small bump compliance, does the same hold for the spring needles?
thanks


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## Jayem (Jul 16, 2005)

Someone posted a while back (dougal?) that the only effect is to lower the effective spring rate. The "binding" that occurs causes the spring to "wind up" a bit, but otherwise there's no real effect or "loss" that you're encountering. Going with a slightly lower spring rate and no bearings has the same effect.


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## pablo4429 (Mar 14, 2008)

ahh got ya, well thanks again Jayem for the informative post.
have people noticed a big difference when changing to needle bearings instead of bushings for the shock mount?


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## Jayem (Jul 16, 2005)

Oh, wait, were you referring to needle bearings around the shock collars (spring), or for your shock pivots?

If you are talking about changing out the shock eyelet bushings for needle bearings, then there can be a difference. It's not always huge, but it's not the same thing I was describing above. It depends on your bike, the leverage ratio and how much rotation your pivots have, but usually there can be an improvement. This is a mod for the people who really can tell small changes in their suspension and are very picky in this regard, but for them, it is worth it.


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## pablo4429 (Mar 14, 2008)

Yes, originally I was talking about around the shock collar, then I asked about the pivot bearings.
So let me see if I have it straight, around the collar, they only modify how much spring weight is needed and in the bushings, depending on the bike's suspension design, it will make it more sensitive....do I have that right?


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## dropadrop (Sep 20, 2005)

pablo4429 said:


> Yes, originally I was talking about around the shock collar, then I asked about the pivot bearings.
> So let me see if I have it straight, around the collar, they only modify how much spring weight is needed and in the bushings, depending on the bike's suspension design, it will make it more sensitive....do I have that right?


Springs have a tendancy to twist a bit when being compressed. That twisting can affect the spring rate a bit, hence the idea of them lowering the spring rate. How much that would effect is really up to the spring and maybe even the linkage on the frame.

Another effect of the spring twisting is that it might actually end up turning the preloader on the shock. I've seen this happen in cases where there is very little preload (so the preload collar is easy to turn) and the shock is very clean (so once again easier to turn the preload collar).


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## Gman086 (Jul 4, 2004)

I have experimented with both. The spring bearings do NOT affect the spring sag nor bottom out resistance whatsoever. They DO allow the spring to go thru it's motion easier = a MORE RESPONSIVE spring. It does NOT change the rate; going to a lower spring rate WILL lower your bottom out resistance IT DOES NOT DO THIS. The diff is noticeable - my rear tire tracks better with them. You only need to do one side for the shock spring (Obtanium bearing kit now includes one bearing and one bushing for each end of the spring).

Pivot bearings - there's usually only one side of the shock that benefits; I highly recommend them on the side that rotates most. They last MUCH longer than the lame shock eyelet bushings and also make the shock more responsive to small inputs/chatter but no diff over the big stuff. 

Overall I'm very happy using both on my FR rig. 

Have FUN!

G MAN


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## pablo4429 (Mar 14, 2008)

Sweet, now what is the difference between the ones you can get from Obtanium or the ones you can piece together from McMaster-Carr, are Obtanium's sealed somehow or something? I am talking about the spring bearings BTW. The total price from McMaster would be like 10 dollars compared to 45 from Obtanium...


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## Gman086 (Jul 4, 2004)

Obtanium has a molded bushing on top to hold the spring in place.


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## SHIVER ME TIMBERS (Jan 12, 2004)

Gman086 said:


> Obtanium has a molded bushing on top to hold the spring in place.


FYI...you can get the needle bearings at any bearing catalog shop...I just got some for front and back for 35 bucks...way cheaper then Obtanium


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## fixbikeguy (Aug 28, 2008)

Can I see a picture of what they look like please?


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## SHIVER ME TIMBERS (Jan 12, 2004)

fixbikeguy said:


> Can I see a picture of what they look like please?


pm me next week


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## eabos (Jun 11, 2005)

fixbikeguy said:


> Can I see a picture of what they look like please?


If I remember, I'll take a pic in the AM and post it up


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## Gman086 (Jul 4, 2004)

SHIVER ME TIMBERS said:


> FYI...you can get the needle bearings at any bearing catalog shop...I just got some for front and back for 35 bucks...way cheaper then Obtanium


Obtanium's are $40 (and fit perfect keeping the spring in place) so you saved a whopping 5 bucks. Also the inner diameter of the outer plastic mates perfectly with my 5th's tension adjuster and spring stop (there are 3 sizes of shock spring diameters depending on brand so be aware of that); good luck finding that with the McMaster Carr version.

Have FUN!

G MAN


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## DHidiot (Aug 5, 2004)

They do NOT lower the springrate or K value. What they do is allow the spring not to torsionally bind deeper into the stroke and allow it to articulate better. I've had them on the last 4 shocks I've used and they make a VERY noticeable difference. I'd say it makes more of a difference on taller edges at speed that will normally use more of your travel. A lot of people end up having to adjust their compression settings to compensate for the more freed-up stroke.

The bearings and washers are cheap, but what you need to securely mount the spring is an adapter that has a longer "skirt" to it to rest inside the bearing, washers, and the spring to keep everything centered up. That's the key part of the Obtanium kit. The stock spring collar on all shocks is NOT long enough for this and will let the spring wander side to side - an unsafe condition in my opinion.

I had the Enduro needle bearings in my eyelets too on the last shock I used. Never again. Noticeable amounts of play even when new, which Enduro claims it is supposed to have. As an engineer I have designed countless needle bearing and shaft interfaces, and none have ever had the tiniest bit of play. They were undergoing higher rotational speeds and way nastier sideloads too. It also has to do with the Enduro bearings not really being real needle bearings - there is no inner cage holding the needles in, so it's simply a bunch of non-precision needles packed in side to side in only an outer cage. That brings me to my final complaint. The outer cage is VERY fragile and cracks/shears if you try to press it out with a conventional DU bushing tool and a proper vice, *****ting the needles everywhere.

I've converted a couple shocks before to proper McMaster or QBC needle bearings, but it requires reaming out the shock eyelets to the next size up. However, no play, great sealing, butter smooth action, and will likely never wear out a reducer again.


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## PsyCro (Jun 8, 2007)

DHidiot said:


> I had the Enduro needle bearings in my eyelets too on the last shock I used. Never again. Noticeable amounts of play even when new, which Enduro claims it is supposed to have. As an engineer I have designed countless needle bearing and shaft interfaces, and none have ever had the tiniest bit of play. They were undergoing higher rotational speeds and way nastier sideloads too. It also has to do with the Enduro bearings not really being real needle bearings - there is no inner cage holding the needles in, so it's simply a bunch of non-precision needles packed in side to side in only an outer cage. That brings me to my final complaint. The outer cage is VERY fragile and cracks/shears if you try to press it out with a conventional DU bushing tool and a proper vice, *****ting the needles everywhere.
> 
> I've converted a couple shocks before to proper McMaster or QBC needle bearings, but it requires reaming out the shock eyelets to the next size up. However, no play, great sealing, butter smooth action, and will likely never wear out a reducer again.


Hmmm.. and me and a few friends were just about to order a bunch of those darn things. Now you've given me something to think about. The last thing we want is play!! Whats the point then??
So reaming out the eyelets, putting in proper needle bearings, and i suppose machining new bushings and shaft?


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## bear (Feb 3, 2004)

I liked the *freer-motion* of the Enduro needles when I put them on my last bike, but also noticed the *free-mount-play*.

Felt like stupid-worn-out DU's.

I thought it may have just been me.

I do NOT like the *free-mount-play* but I don't know that it was truly harmful (to the bike/shock) - does anyone else?

( clarified, coffee hadn't kicked in, sorry )


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## CrustyOne (Oct 29, 2007)

That made no sense


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## CrustyOne (Oct 29, 2007)

The play wont really harm anything but it just feels crappy...and do you really want to spend money on such a poorly engineered but hyped up component?


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## derby (Jan 12, 2004)

DHidiot said:


> They do NOT lower the springrate or K value. What they do is allow the spring not to torsionally bind deeper into the stroke and allow it to articulate better. I've had them on the last 4 shocks I've used and they make a VERY noticeable difference. I'd say it makes more of a difference on taller edges at speed that will normally use more of your travel. A lot of people end up having to adjust their compression settings to compensate for the more freed-up stroke.


It does sound from your experience that the spring rate becomes less progressive deep in travel. The coil width expansion is eliminated with a roller perch.

I don't "see" any binding of a coil without a roller bearing perch, unless the expansion is limited by a close reserve chamber or frame.

I don't see how the spring resistance isn't softer using a roller perch. Again is may be less progressive and more noticeably softer in deeper travel.


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## captain spaulding (May 7, 2006)

DHidiot said:


> I've converted a couple shocks before to proper McMaster or QBC needle bearings, but it requires reaming out the shock eyelets to the next size up. However, no play, great sealing, butter smooth action, and will likely never wear out a reducer again.


DHidiot: Do you mind sharing some of your knowledge on this? Like what to ream the eyelets out to? I'm sure I can figure out what Needle Bearings(I love looking at all the cool stuff in mcmaster's website)..

I would ask you about the needle bearings for the spring, but I feel like everything isn't "off-the-shelf" per say(the adapter part of it).


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## DHidiot (Aug 5, 2004)

I'll look up the numbers for the ream and shaft diameter later. We used whatever needle bearing was in QBC that had a 1/2" width. I think it was a .6875 OD??

I ended up machining my own aluminum adapter for it. Just a cylinder with an inside shoulder (for the existing shock collar) and a large outside shoulder on the other side (wide enough for the spring and bearing, deep enough to center all of them up). Made it for a 1.5 spring because that was the Ti spring I was using at the time.


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## DHidiot (Aug 5, 2004)

11/16" OD, 1/2" ID, 1/2" width. So ream to 11/16" (or 0.6875") and it'll be a perfect press fit. No retaining compound necessary.

Disclaimer: I am in no way responsible for anything resulting from anyone drilling holes in their shocks.


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## captain spaulding (May 7, 2006)

DHidiot said:


> 11/16" OD, 1/2" ID, 1/2" width. So ream to 11/16" (or 0.6875") and it'll be a perfect press fit. No retaining compound necessary.
> 
> Disclaimer: I am in no way responsible for anything resulting from anyone drilling holes in their shocks.


Awesome, that's actually the size I came up with by eyeballing some stuff.. Mcmaster part number is: 5905K23


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## captain spaulding (May 7, 2006)

DHidiot said:


> I ended up machining my own aluminum adapter for it. Just a cylinder with an inside shoulder (for the existing shock collar) and a large outside shoulder on the other side (wide enough for the spring and bearing, deep enough to center all of them up). Made it for a 1.5 spring because that was the Ti spring I was using at the time.


1.5" Inside diameter spring? Vivid spring? Assuming you used 1.5" ID needle bearings to match up w/the spring?


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## Secace (Sep 8, 2004)

I'm subscribing to this. Thanks DHidiot for the pivot bearing info. I just outfitted all three of my bikes with Enduro needle bearing kits. I too notice substantial play in the mounting points....moreso than the worn DU bushing the bearings replaced. The play is barely noticeable while riding though....just when standing there lifting up on the back of the seat. They definitely make a difference in providing a smoother ride. But that play gets on my nerves just knowing it exists. When they finally die, I'm going the route of DHidiot and going to better quality bearings.


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## DHidiot (Aug 5, 2004)

captain spaulding said:


> 1.5" Inside diameter spring? Vivid spring? Assuming you used 1.5" ID needle bearings to match up w/the spring?


Romic spring, but same dimensions. Got it cheap and that's what was convenient. The 1.5 ID bearings match up to the ID and OD of the spring quite nicely.

I noticed the play quite a bit when riding through chattery sections that would have the wheel leaving the ground momentarily. Going back to a fresh and tight DU setup transmits a lot less jarring force through the frame.


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## katsooba (Nov 21, 2008)

is this the coil bearing you guys are talking about?
http://www.mcmaster.com/#thrust-bearings/=9e35rq

well cant seem to link it correctly,
the bearing model im talking about is 5909K18

35ID\52OD

or a smaller one?
i have the lower spring holder cup right next to me and it seems like its

33mm ID and 46mm OD in the coil groove

the closest bearing for this is the 35 \ 52

i think its a bit too big

or am i missing something here?


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## Dougal (Jan 23, 2004)

DHidiot said:


> They do NOT lower the springrate or K value. What they do is allow the spring not to torsionally bind deeper into the stroke and allow it to articulate better. I've had them on the last 4 shocks I've used and they make a VERY noticeable difference. I'd say it makes more of a difference on taller edges at speed that will normally use more of your travel. A lot of people end up having to adjust their compression settings to compensate for the more freed-up stroke.


How do you differentiate between a spring "torsionally binding" (i.e. assuming a higher rate due to end restraint) and the actual spring rate?
Maybe it's just me, but I don't see the difference. If you let one end freely rotate to prevent binding, then it's less force to compress which is effectively a lower spring rate.



DHidiot said:


> I had the Enduro needle bearings in my eyelets too on the last shock I used. Never again. Noticeable amounts of play even when new, which Enduro claims it is supposed to have. As an engineer I have designed countless needle bearing and shaft interfaces, and none have ever had the tiniest bit of play. They were undergoing higher rotational speeds and way nastier sideloads too. It also has to do with the Enduro bearings not really being real needle bearings - there is no inner cage holding the needles in, so it's simply a bunch of non-precision needles packed in side to side in only an outer cage. That brings me to my final complaint. The outer cage is VERY fragile and cracks/shears if you try to press it out with a conventional DU bushing tool and a proper vice, *****ting the needles everywhere.


I'm currently running a RWC needle bearing kit and there's no noticable play in mine. Where did you source yours? It's possible a bad batch of bearings got out. There is also the tolerance of the shock eyes which becomes the tolerance in the bearing when they're installed. 
The real solution I guess is custom shock pins which are fitted to each needle bearing when installed in the shock eyelet. Fairly tedious though.

How much improvement you notice with needle bearings in shock eyes depends almost entirely on how good your hardware was before. The standard fox aluminium reducers can be soo tight they can't be turned without tools. A well toleranced 3 piece setup can be spun with your fingers but still has no noticable play when installed.



DHidiot said:


> I've converted a couple shocks before to proper McMaster or QBC needle bearings, but it requires reaming out the shock eyelets to the next size up. However, no play, great sealing, butter smooth action, and will likely never wear out a reducer again.


16mm?


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## Jayem (Jul 16, 2005)

Dougal said:


> How do you differentiate between a spring "torsionally binding" (i.e. assuming a higher rate due to end restraint) and the actual spring rate?
> Maybe it's just me, but I don't see the difference. If you let one end freely rotate to prevent binding, then it's less force to compress which is effectively a lower spring rate.


Yeah, the spring is simply acting as a spring in different direction (torsion). If there was truly resistance to movement and not just a change in spring rate due to this effect, then you'd have heat buildup and wear, as you'd be damping movement.


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## DHidiot (Aug 5, 2004)

Well, there IS wear. Look at the end of your spring where the paint is all scratched off and the collar is marred up.

Springrates are measured in the axial (linear) direction. They can also act torsionally with minimal linear compression, same as a formal torsion spring operates. De-coupling that lets you use the ACTUAL linear springrate (or K value) through the entire stroke. A huge amount of friction at the flat ends of the spring (which gets higher and higher with more force against it throughout the stroke) is what prevents the ends from migrating in a circular direction the way they would want to naturally. The longer the stroke and the larger the coil spacing (or coil angle), the more prone to binding they are.

Just think of it as a leaf spring between to parallel plates. If you compress it, it's gonna slide against at least one of the plates. Only this one is wrapped into a coil, and the two plates are the spring collars.

It's less force to compress the spring deeper in the stroke with the two directions de-coupled. More linear, same springrate. 


I was using the RWC kit at both ends. I didn't buy them for smoothness necessarily - my current frame has very little rotation at either eyelet. 20-25 degrees at most. I bought them so I'd never have that slop in the back end and so I'd never be going through reducers again. I think if they were installed ONCE, and the pin were precision fit with gauge pins, they'd work well and be a long term solution. I do not think it's out of the question that differences in the diameter of the shock eyelet could change the ideal fit diameter of the shaft. Those cages were pretty weak.


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## Dougal (Jan 23, 2004)

DHidiot said:


> Springrates are measured in the axial (linear) direction. They can also act torsionally with minimal linear compression, same as a formal torsion spring operates. De-coupling that lets you use the ACTUAL linear springrate (or K value) through the entire stroke. A huge amount of friction at the flat ends of the spring (which gets higher and higher with more force against it throughout the stroke) is what prevents the ends from migrating in a circular direction the way they would want to naturally. The longer the stroke and the larger the coil spacing (or coil angle), the more prone to binding they are.


That's exactly what I mean. Spring rates are measured with both ends fixed. If you let one end rotate freely then your measured spring rate will reduce. I don't think it's about deeper in the stroke either. The rotation possible depends on the angle of the spring coils, as the spring compresses further this reduces, the rotation is highest per amount of compression when the spring starts at full compression.



DHidiot said:


> I was using the RWC kit at both ends. I didn't buy them for smoothness necessarily - my current frame has very little rotation at either eyelet. 20-25 degrees at most. I bought them so I'd never have that slop in the back end and so I'd never be going through reducers again. I think if they were installed ONCE, and the pin were precision fit with gauge pins, they'd work well and be a long term solution. I do not think it's out of the question that differences in the diameter of the shock eyelet could change the ideal fit diameter of the shaft. Those cages were pretty weak.


If you're after no detectable play and long life. Then IGUS with good three piece hardware is where you should be. Needle rollers are a minimum friction solution, I don't sell them to people wanting fit and forget.

DU bushings are for people wanting the cheapest replacements.
IGUS bushings are for people wanting the longest life.
Needle rollers are for people wanting minimum friction. But they do need maintained.


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## DHidiot (Aug 5, 2004)

I would have to assume that the springs are measured with some amount of freedom torsionally. Ideal springs in studies of dynamics have a linear rate K, but in practical applications it's common knowledge to assume more progressiveness than the nominal rate for this reason.

What is cost like on the IGUS bushings in the sizes necessary for a rear shock? Direct fit or reaming required?


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## Dougal (Jan 23, 2004)

DHidiot said:


> I would have to assume that the springs are measured with some amount of freedom torsionally. Ideal springs in studies of dynamics have a linear rate K, but in practical applications it's common knowledge to assume more progressiveness than the nominal rate for this reason.
> 
> What is cost like on the IGUS bushings in the sizes necessary for a rear shock? Direct fit or reaming required?


Normal springs also gain progression from the closed ends coming into contact and reducing the number of free coils. It can be a big effect on a short coil spring.

I sell DU bushings for $NZ5 and IGUS for $NZ15. That's about $US3.5 and $US10.50 depending on the current exchange rate. Untracked postage worldwide is pretty cheap and so far all our international orders have made their destination.
They are a straight replacement for the 1/2x1/2 DU bushings, we also have them to fit 12mm shock eyelets, GT i-drive dog bones and a lot more applications. Of course 3 piece hardware prolongs the life of any bushing.

The failure mode on an IGUS bush in a shock eye is they eventually get hammered out of shape. This takes a few years of solid riding and is usually at least 4 DU bushings worth.


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## bear (Feb 3, 2004)

Dougal, assuming equivalent (decent) hardware how is the "feel" of the IGUS vs DU? I kind-of want to say for most applications it'd be hard to tell a difference in suspension behavior on the trail, but you're the guy with the parts and (theoretically) the experiential knowledge.

Also, what do you think of BETD's 2-piece hardware set?


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## Dougal (Jan 23, 2004)

bear said:


> Dougal, assuming equivalent (decent) hardware how is the "feel" of the IGUS vs DU? I kind-of want to say for most applications it'd be hard to tell a difference in suspension behavior on the trail, but you're the guy with the parts and (theoretically) the experiential knowledge.
> 
> Also, what do you think of BETD's 2-piece hardware set?


You won't notice any difference in feel between a DU and an IGUS. Though I have to qualify that with the DU bushings I have are PTFE (teflon) and lead with the black surface to them which probably slides better than the red coating (I think it's PU) on the fox DU bushings.

Do you mean the "strong" bush sets that BETD sell? They're basically a 3 piece but one collar is part of the pin. They'll do the job, but I'd prefer people to buy shock hardware off me. 
I use plastics for the collars on most applications, they are lighter and can't scratch up the shock eye. I also do aluminium for people who want the shiney look, especially with needle rollers where they have quadring seals to prevent contact anyway.

If people are really worried about weight, I can also do a hollowed out lightweight steel pin, depending on the size of the pin and bolt I can save half the weight from the hardware. It took 30g off the wife's Intense but that's probably best case as they use a long pin (58mm) with 6mm bolts.

Some pretty pictures here:
http://dougal.co.nz/shockcraft.co.nz/hardware.html
http://dougal.co.nz/shockcraft.co.nz/pdf/shockcraft_shock_hardware.pdf


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## Gman086 (Jul 4, 2004)

I have the RWC Enduro eyelet needle bearings and there is ZERO play! In fact, I had to hone out the eyelets slightly as there was actually some binding so... I think it could be shock dependant. RWC makes a GREAT product that also is SEALED with custom rubber o-rings inside custom end caps (can you say LESS maintenance?). Again... good luck getting that from McMaster Carr!

And Dougal.. the rate change (with spring bearings), if any, is minimal but the spring's reaction time speeds up - you couldn't be MORE WRONG! Try it before you diss it... all this conjecture makes me laugh!

Have FUN!

G MAN


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## Dougal (Jan 23, 2004)

Gman086 said:


> I have the Enduro eyelet needle bearings and there is ZERO play! In fact, I had to hone out the eyelets slightly as there was actually some binding so... I think it could be shock dependant. Enduro makes a GREAT product that also is SEALED with custom rubber o-rings inside custom end caps (can you say LESS maintenance?). Again... good luck getting that from McMaster Carr!


The RWC kits are made by RWC (Real World Cycling). They use an Enduro needle roller bearing, but they are not an enduro product.



Gman086 said:


> And Dougal.. the rate change (with spring bearings), if any, is minimal but the spring's reaction time speeds up - you couldn't be MORE WRONG! Try it before you diss it... all this conjecture makes me laugh!


Speeding up the reaction time of spring steel. Oh lordy. Back to school for you.


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## Gman086 (Jul 4, 2004)

Okay smartass... then why don't I bottom out a 400 lb spring with them yet I DO bottom out a 375 lb spring WITHOUT them? My rear wheel tracks BETTER because the spring is more reactive AND more efficient, certainly not because the rate changed!

Have FUN!

G MAN


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## Dougal (Jan 23, 2004)

Gman086 said:


> Okay smartass... then WTF don't I bottom out a 400 lb spring with them yet I DO bottom out a 375 lb spring WITHOUT them? My rear wheel tracks BETTER because the spring is more reactive AND more efficient, certainly not because the rate changed!
> 
> Have FUN!
> 
> G MAN


Reaction speed and efficiency of steel springs is not a problem. They react faster than you can measure them and return the vast majority of energy stored in them.
Of course these springs are always coupled with a damper (usually oil) which has two goals, controlling the speed of reaction and dissipating energy.

Have you measured the rate of those springs or just going by the numbers on the side? There's a pretty wide tolerance on bike shock springs, those rates could be a lot different to what you expect.
Not to mention how many variables there are in riding the same place twice. Different speed, different line, different amount of food for lunch etc, etc, etc.


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## CrustyOne (Oct 29, 2007)

Gman086 said:


> Okay smartass... then WTF don't I bottom out a 400 lb spring with them yet I DO bottom out a 375 lb spring WITHOUT them?
> G MAN


......are you serious?.....you dont perhaps think its logical to bottom out a 375lb spring but not a 400lb spring?

forget all that bearing bollox, get a grip on the basics...oh lordy

(p.s. if you really think the bearing makes a 25lb+ difference in spring rate...well I give up)


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## SHIVER ME TIMBERS (Jan 12, 2004)

Gman086 said:


> Obtanium's are $40 (and fit perfect keeping the spring in place) so you saved a whopping 5 bucks. Also the inner diameter of the outer plastic mates perfectly with my 5th's tension adjuster and spring stop (there are 3 sizes of shock spring diameters depending on brand so be aware of that); good luck finding that with the McMaster Carr version.
> 
> Have FUN!
> 
> G MAN


for 2 sets...one on each side???


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## Gman086 (Jul 4, 2004)

CrustyOne said:


> ......are you serious?.....you dont perhaps think its logical to bottom out a 375lb spring but not a 400lb spring?
> 
> forget all that bearing bollox, get a grip on the basics...oh lordy
> 
> (p.s. if you really think the bearing makes a 25lb+ difference in spring rate...well I give up)


I guess you can't read? Dougal insists that the bearings are the same as dropping down a size on spring rate so grip that basic pal... oh LORDY!   

Have FUN!

G


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## Gman086 (Jul 4, 2004)

SHIVER ME TIMBERS said:


> for 2 sets...one on each side???


You DON'T NEED TWO SETS!!!

And DHidiot hit the nail on the head here (the only one who has some semblance of sanity in this thread): 
>>The bearings and washers are cheap, but what you need to securely mount the spring is an adapter that has a longer "skirt" to it to rest inside the bearing, washers, and the spring to keep everything centered up. That's the key part of the Obtanium kit. The stock spring collar on all shocks is NOT long enough for this and will let the spring wander side to side - an unsafe condition in my opinion.<<

Like I said Bob... good luck with your do-it-yourself version! What really cracks me up is that you guys spend thousands on your bikes but are too stinkin cheap to spend $5-15 more for properly sealed bushing/bearing kits. And, uhm, yes... it DOES cost money for the tooling to make the custom skirts thus the cost difference.

Have FUN!

G MAN


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## Deerhill (Dec 21, 2009)

*6mm w/ sleeve?*

dblpost


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## Deerhill (Dec 21, 2009)

*6mm w/ sleeve?*



Gman086 said:


> I have the RWC Enduro eyelet needle bearings and there is ZERO play! In fact, I had to hone out the eyelets slightly as there was actually some binding so... I think it could be shock dependant. RWC makes a GREAT product that also is SEALED with custom rubber o-rings inside custom end caps (can you say LESS maintenance?). Again... good luck getting that from McMaster Carr!
> 
> And Dougal.. the rate change (with spring bearings), if any, is minimal but the spring's reaction time speeds up - you couldn't be MORE WRONG! Try it before you diss it... all this conjecture makes me laugh!
> 
> ...


What size bolt and which rwc kit do you have?


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## CrustyOne (Oct 29, 2007)

Gman086 said:


> WTF?! I guess you can't read? Dougal insists that the bearings are the same as dropping down a size on spring rate so grip that basic pal... oh LORDY!
> 
> Have FUN!
> 
> G


..and how does an arrogant sidestep change your stupid (and quite wrong) remark?


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## Gman086 (Jul 4, 2004)

CrustyOne said:


> ..and how does an arrogant sidestep change your stupid (and quite wrong) remark?


Let me spell it out for you...

Of COURSE you'd bottom out a 375 lb spring before a 400 lb spring but Dougal insists that the washer bearings have the same affect as going down one size on spring rate SO... following his logic (which you can't seem to grasp) I should ALSO bottom out the 400 lb spring IF it has the spring bearings. That does NOT happen - Dougal's hypothesis is WRONG and he tried to backtrack out of it saying the springs I used may be off the stated rating.

Have FUN!

G MAN

PS - And arrogant??? Hardly, I just don't put up with garbage from someone who didn't bother to READ the thread!


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## Gman086 (Jul 4, 2004)

DeerhillOG said:


> What size bolt and which rwc kit do you have?


I have the Iron Horse specific kit that includes custom bolts:
http://www.enduroforkseals.com/id323.html

Have FUN!

G


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## Deerhill (Dec 21, 2009)

*custom bolts*



Gman086 said:


> I have the Iron Horse specific kit that includes custom bolts:
> http://www.enduroforkseals.com/id323.html
> 
> Have FUN!
> ...


make sense. I was hoping you had a 8mm... I wish there was a custom bolt for the RWC 22mm Item #: NBKRWC22. The kit is quite loose using an 8mm bolt. Tops out on jumps pretty hard. I haven't taken it back out to measure, but maybe these are all made for a 10mm bolt?


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## bear (Feb 3, 2004)

Thanks for the info Dougal. appreciated. I may have to get some stuff from you just 'cause (I need some more bushings for my winter overhaul anyway...)


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## DHidiot (Aug 5, 2004)

FYI the tolerance on the nominal springrates (at least for steel MTB springs) is something like +/-15%. That means that as soon as you go over about 225# the tolerance is GREATER than the interval between available springrates (for 25# increments in low leverage applications), and around 350-400# the tolerance is greater than the 50# increments between weights. 

It's worth keeping a properly measured Ti spring that can be moved between bikes for your weight. At the end of the day, with the spring bearing perches or without, you still have to set up the bike with 30-33% sag with minimal preload. Just gotta find a spring that does that if you want the bike to ride correctly.

The difference caused by the thrust bearings isn't really enough to throw off the sag measurement more than maybe a turn of preload. As said before, the change is more evident on sudden deep-travel impacts. If anything it makes your rebound stroke more linear too.


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## Dougal (Jan 23, 2004)

Gman086 said:


> WTF?! I guess you can't read? Dougal insists that the bearings are the same as dropping down a size on spring rate so grip that basic pal... oh LORDY!
> 
> Have FUN!
> 
> G


No, there is a big difference between "a reduction in spring rate" and "going down a size".


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## Dougal (Jan 23, 2004)

bear said:


> Thanks for the info Dougal. appreciated. I may have to get some stuff from you just 'cause (I need some more bushings for my winter overhaul anyway...)


I look forward to it.


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## Gman086 (Jul 4, 2004)

Dougal said:


> No, there is a big difference between "a reduction in spring rate" and "going down a size".


Well we're all still waiting for your proof that this reduction exists! Honestly now... have you ever even bothered to try them?


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## Dougal (Jan 23, 2004)

Gman086 said:


> Well we're all still waiting for your proof that this reduction exists! Honestly now... have you ever even bothered to try them?


Grab a pen spring, compress it by hand while allowing one end to rotate then by holding both ends fixed. It's pretty obvious.


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## DHidiot (Aug 5, 2004)

We've observed between 10-15 degrees of rotation through the stroke on a 350# 3" stroke spring (Romic, 6-6.5 active coils I believe?). Had someone real heavy just sit on the bike and bottom it. Pretty interesting. Removed the thrust bearing and saw zero rotation at either end. 

If we were motivated enough we could probably find a way to measure spring bowing and deflection under each scenario. But we're not.


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## captain spaulding (May 7, 2006)

DeerhillOG said:


> make sense. I was hoping you had a 8mm... I wish there was a custom bolt for the RWC 22mm Item #: NBKRWC22. The kit is quite loose using an 8mm bolt. Tops out on jumps pretty hard. I haven't taken it back out to measure, but maybe these are all made for a 10mm bolt?


The Ironhorse kit includes an adapter to run their standard 30mm needle bearing kit. Pretty sure the bolt/nut is 8mm.


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## Deerhill (Dec 21, 2009)

*so not custom bolts?*



captain spaulding said:


> The Ironhorse kit includes an adapter to run their standard 30mm needle bearing kit. Pretty sure the bolt/nut is 8mm.


I was looking at the link gman referred to which says 10mm hardware http://www.enduroforkseals.com/id323.html

So the adapter is a sleeve that goes over an 8mm bolt which makes it 10mm?


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## Gman086 (Jul 4, 2004)

DeerhillOG said:


> I was looking at the link gman referred to which says 10mm hardware http://www.enduroforkseals.com/id323.html
> 
> So the adapter is a sleeve that goes over an 8mm bolt which makes it 10mm?


Yes


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## captain spaulding (May 7, 2006)

Nice know there isn't play in the ironhorse kit(I was looking to get the kit for my mk3).. I got the 40mm kit+spacers for my shocker and there's a bunch of play(play is def. coming from the shock eyelet area).. really annoying..


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## Deerhill (Dec 21, 2009)

Gman086 said:


> Yes


Do the NBKRWC22 and the NBKRWC30-IH bearings have the same inside diameter?

Was the Iron horse sleeve developed later, is it a larger outside diameter than the others?


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## Deerhill (Dec 21, 2009)

captain spaulding said:


> Nice know there isn't play in the ironhorse kit(I was looking to get the kit for my mk3).. I got the 40mm kit+spacers for my shocker and there's a bunch of play(play is def. coming from the shock eyelet area).. really annoying..


 Maybe the sleeve on the Ironhorse kit can be used or cut down for other kits to get rid of the play...


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## Gman086 (Jul 4, 2004)

The sleeve was only developed because the IH bikes have a very specific bolt with a recessed head that is no longer made. The sleeve has the recessed head and that is the only reason for it.


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## Dougal (Jan 23, 2004)

Gman086 said:


> The sleeve was only developed because the IH bikes have a very specific bolt with a recessed head that is no longer made. The sleeve has the recessed head and that is the only reason for it.


Does anyone have a picture of this setup?


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## Deerhill (Dec 21, 2009)

Dougal said:


> Does anyone have a picture of this setup?


I'm buying the sleeve if the bearings are the same for both kits.


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## captain spaulding (May 7, 2006)

DeerhillOG said:


> I'm buying the sleeve if the bearings are the same for both kits.


The sleeve only works for IH bikes, there's no point to buy this kit UNLESS you have a IH bike.. This is a normal 8x30mm RWC kit that includes the sleeve/bot/nut to convert the mounting hardware from 10mm to 8mm to so you can use the RWC kit.


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## Deerhill (Dec 21, 2009)

Dougal said:


> I'm currently running a RWC needle bearing kit and there's no noticable play in mine. Where did you source yours? It's possible a bad batch of bearings got out. There is also the tolerance of the shock eyes which becomes the tolerance in the bearing when they're installed.
> The real solution I guess is custom shock pins which are fitted to each needle bearing when installed in the shock eyelet. Fairly tedious though.
> 
> How much improvement you notice with needle bearings in shock eyes depends almost entirely on how good your hardware was before. The standard fox aluminium reducers can be soo tight they can't be turned without tools. A well toleranced 3 piece setup can be spun with your fingers but still has no noticable play when installed.


What frame, shock and RWC kit are you using? Would be really nice to get rid of the play


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## Dougal (Jan 23, 2004)

DeerhillOG said:


> What frame, shock and RWC kit are you using? Would be really nice to get rid of the play


This is a vanilla RC (the old school version), Turner RFX/5 Spot (Horst link) and 22mm RWC kit.

I had a close look the other day and if I rest my fingers on it while pushing/pulling I can feel the slightest amount of play with my fingertips. But not while riding.
By my measurements I have about 0.04mm of clearance in these eyelet bearings, which is just below the point where you can feel it while riding. At 0.1mm clearance it's very obvious, between 0.1 and 0.05mm some people will notice and others won't.


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## saturnine (Mar 28, 2007)

i'm using an rwc needle bearing kit on my enduro and there is no play. they are infinitely smoother and rotate more freely than the stock specialized reducers.


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