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Discussion Starter · #1 ·
I have a small play in Maestro rear suspension (Giant Anthem 2) - I understand, it could be loose bolts, worn bearings or worn bushings.
I had a look at the bushings, and there is a thing I'm now quite sure about: the bushing is sitting tightly in the eyelet of rear shock, two alloy mounting pieces are inserted into the bushing tightly as well, the mounting pieces are inserted into the rocker arm and screwed tightly by a bolt. Now, as suspension moves, the rear shock has to compress and expand, but also rotate a little bit. This is the part I'm not sure - where the rotating movement happens - (1) bushing against eyelet? (2) mounting pieces against the bushing? or (3) the mountng pieces against the rocker arm. Similar question about other end of the shock.
 

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Answer = (2) mounting pieces against the bushing.

The bush itself should be pressed solidly in to the shock eyelet (1) and never rotate during use (or it'd ruin your shock real quick).

The mounting hardware should be clamped solid between the rocker arm/frame mounts (3) by the bolt holding it together and again should not rotate in use.

The two alloy mounting pieces (hats) should be a tight fit into the bushing too, but they are designed to rotate against the bushing lining material long before anything else should rotate. You probably shouldn't be able to rotate those mounting pieces by hand either or it could indicate a worn bushing lining, but you should find they'll rotate no problem under the leverage forces experienced when riding.
 

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Discussion Starter · #3 ·
Aha, this makes sense, thanks for the reply. And to add to my suspicion that bushing is probably worn, the mounting pieces simply fallen out when I removed the bolt. On the other end of the shock they stayed put quite tightly. Thanks again
 

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Biking Like Crazy!
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nampla said:
Aha, this makes sense, thanks for the reply. And to add to my suspicion that bushing is probably worn, the mounting pieces simply fallen out when I removed the bolt. On the other end of the shock they stayed put quite tightly. Thanks again
Could be BOTH the bushing and mounting hardware!

Should get both while ordering because these are high wear items and you'll need them eventually!! :thumbsup:
 

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There's another option too. Replace the tight fitting 2 piece hardware with better toleranced 3 piece.
You get easier and smoother rotation, longer bushing life and you'll never bend or break a bolt again. Maintenance free too. Rotation isn't quite as effortless as the RWC needle roller bearings but it's a huge improvement on the 2 piece design.

Does anyone know why fox etc make their hardware a press fit? None of the manufacturers data I've found on DU bushings backs this up.
 

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Dougal said:
Here's a more up-to-date photo. This one was done for a customer in Canada who wanted oring and quadring seals.

That is a nice looking kit, and in my opinion this reducer system is currently the best solution for the reducer interface (especially on suspension designs that have a lot of rotation at the shock mount points). Until the RWC kit is proven to be completly play-free for brand new installs I go with this stuff.

I have posted on another thread about the multiple benefits of this single steel pin type system over the standard 2 piece reducer, so maybe look for that so you have a good understanding of all the forces at work there (or maybe Dougal will feel like typing something up)

Also, I know Dougal makes these pieces for his business, but a couple manufactures make kits like this available for their shocks (for a small fee), Fox and Cane Creek specifically. Just call them and tell them what you need.
 

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IntenseMack10 said:
That is a nice looking kit, and in my opinion this reducer system is currently the best solution for the reducer interface (especially on suspension designs that have a lot of rotation at the shock mount points). Until the RWC kit is proven to be completly play-free for brand new installs I go with this stuff.

I have posted on another thread about the multiple benefits of this single steel pin type system over the standard 2 piece reducer, so maybe look for that so you have a good understanding of all the forces at work there (or maybe Dougal will feel like typing something up)

Also, I know Dougal makes these pieces for his business, but a couple manufactures make kits like this available for their shocks (for a small fee), Fox and Cane Creek specifically. Just call them and tell them what you need.
Thanks Mack

The interesting thing about the fox three piece reducers is the pins are oversize by about 0.03mm. That might not sound like much but it makes them a very tight fit (you can't fit them in without tools) and gives them a lot of resistance to rotation. I have no idea why they do this, I've been running my tolerances for about 6 years now and I haven't found a downside yet.

I haven't had the chance to measure up any Cane Creek or Rockshox 3 piece hardware, one of the downsides of being on the service side is you don't get to do autopsy's on parts that are working fine.

Nicolai had a directive that two piece shock hardware shouldn't be used on anything wider than 24mm due to bending loads and I agree with that totally. But even below 24mm there are benefits to bushing life and ease of rotation. I have been working on some pretty FEA plots to show the problems with wider 2 piece shock hardware, but there's a big difference between creating an FEA plot for my or another engineers information and creating two for general public consumption to highlight the differences.
 

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Dougal said:
I haven't had the chance to measure up any Cane Creek or Rockshox 3 piece hardware, one of the downsides of being on the service side is you don't get to do autopsy's on parts that are working fine.
I've ordered a good number of the Rock Shox and Cane Creek reducers for folks and they have been spot on with regards to fit, form and function. I've tested the Rock Shox reducers on my rig with no problems. Marzocchi makes a stainless steel pin reducer but the sleeves have no seals or orings.....but functional.

I think the RWC Needle Bearing kit is well designed but I [my opinion] just see no reason to move away from DU Bushings to a system that has play from the onset. I tested the Needle Bearing Kit on one eyelet.....it developed play after a few rides.....I tossed it and went back to the DU Bushing.

And for the folks that migrate to the Igus poly bearing.....you better be using a thru pin reducer and not the hat style. Igus recommends a thru pin type axle....stainless steel the best option. I did some testing with one and the hat style reducers. The igus bearing came out of the eyelet bore about 0.50 mm due to excessive side-play in the reducer......interesting wearing patterns.

It's been my experience that folks fail to understand they need to replace the reducers at some period of time not just the DU Bushing. But why do frame manufactures or Fox still source the "Hat" Style reducers with new frames......seems like they should transition to thru shaft type. A few month back in the TItus forum their was a great example of the failures of the Hat style reducers.....they flexed (long span) and caused the bolt to failure in bending. A load the bolt should have never seen.

.
 

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mtnbiker4life said:
I think the RWC Needle Bearing kit is well designed but I [my opinion] just see no reason to move away from DU Bushings to a system that has play from the onset. I tested the Needle Bearing Kit on one eyelet.....it developed play after a few rides.....I tossed it and went back to the DU Bushing.
I've been riding the RWC kit on one of my shocks (I swap them around a bit) since October. Play hasn't increased since fitting and was measured a week or so ago at 0.03-0.04mm. I swapped to the new tighter tolerance bearing and measure 0.01mm which is pretty good. The biggest variable they have is the tolerance of the shock eyelet itself, fox ones seem quite consistent (at least all mine are), but other brands are all over the place.

mtnbiker4life said:
And for the folks that migrate to the Igus poly bearing.....you better be using a thru pin reducer and not the hat style. Igus recommends a thru pin type axle....stainless steel the best option. I did some testing with one and the hat style reducers. The igus bearing came out of the eyelet bore about 0.50 mm due to excessive side-play in the reducer......interesting wearing patterns.
Yes Igus needs a solid steel pin, which is exactly what I make. There are only two reasons for the fox top hat reducers to exist, they're cheap and they're light. You can match (even beat) the weight with an alloy three piece setup, but you give up a lot of durability for only a few grams.
 
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