Can anybody explain how shock bushings work?

Currently have a Pearl 3.1 looking to upgrade it.

If I buy the replacement Pearl sized bushings, which I think are 12.7mm does that then mean it will fit my frame, or do I need special bushings to fit my frame

If I was to buy a shock with bushing already fitted, can I presume that it will fit in my frame or not?

The shock determines the bushing size (i.e. the 12.7 bit) and the shock &frame dictates the bolt size/ DU bush spacer.

Bushing (DU bush) = ring shaped things that go in the shock eyelets (12.7mm diameter in your case).

Reducer (or mount kit) = aluminium (or sometimes steel) pieces that fit the shock to your frame. These are different diameters (depending on the shock bushing size) and widths (depending on the frame).

Which bit are you wanting to replace? The bushing is designed to be the sacrificial piece that wears (although alu reducers will need replacing after a while, but should last a few bushes).

http://www.tftunedshox.com/info/mount_kits_bushings.aspx

Yeah like above really, a lot of shocks run the 1/2″ inner eyelete bush, however the mounting bushes or outer eyelete bushes are specific to the frames.

Also the outer eyelet bushes can have different diamter bolt holes, 8mm which is common and 6mm which is less common. You also get 10mm and some specialized frames run an axle that goes right through the shock so 15mm.

Hope that made sense 😀

Also, did you get that problem with the bolt fixed and if not can I have a go at it please ❗ ❓

I am no expert but you basically have 2 parts that need to match up to fit a new shock to your frame, that is the shock (this should have the same shock length and stroke as the previous shock) and the mounting kit.

The pic in this add has the mounting kit still in the shock eyelets
http://cgi.ebay.co.uk/Fox-Float-RP23-Rear-Shock-6-5-x1-5-165mm-x-38-4mm-/190546766668?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item2c5d78eb4c
The bushes sit between the shock eyelet and the mounting kit.

If you have a shock with 12.7mm eyelets you will have the specific mounting kit for that size. I think the other size is 12mm so if you get a shock with 12mm bushes your mounting kit will not fit and vice a verse if you have 12mm mounting kit and get a 12.7mm eyelet shock it will wallop about like a willy in a shirt sleeve and be all but useless.

My advice would be speak to the guys at TF Tuned, Mojo or Loco as they will be able to advise on the best replacement to match your frame as well as insuring there will be no incompatibility issues.

Also, did you get that problem with the bolt fixed and if not can I have a go at it please

Not yet, it’s in the boot of the car just now. Hectic week at work is going to delay any work on it.

Right then

THat’s me more confused.

At either end I ahve two things which I believe are called .

Two of them fell straight off at the frame side when taken off, no idea if they are meant to.
Other two are still stuck in because of bolts.

Are those bits that I need to replace or not?

Note: I actually rode right around the red route at GT with the snapped bolt. I thought there was a bit of play in the rear shock, but decided one last ride would be ok.

Top hats + through bolts = mounting kits

I would recommend trying to source some replacement mounting kits before going to the expence of replacing the shock especially if you have a jammed bolt in one of them. There is a couple of sets on ebay that my work depending on the age of your frame.

below is a link to TF Tuned that my help explain my jumbled ramblings

http://www.tftunedshox.com/info/mount_kits_bushings.aspx

[edit] here is a link to a heap of bushings from TF Tuned, hopefully one will be the correct dimentions, if you do not know the size you need they may be able to help you out.

http://www.tftunedshox.com/Miscellaneous/Mount-Kits-and-Bushings/Mount-Kits-127mm

You will need to repalce the inner eyelet bushes, you may also have to replace the outer eyelet bushes.

The reason the bolt snapped is probably play in the bushes, leading to fatigue of the bolt.

I have a box of spare bushes and those look like 20 maybe 22mm width by 8mm bore.

Chuck it in the post and let me have a shot of fixing it.

Job done and I’ll tell you how I got it out.

Come on, let me solve the puzzle 💡

Send me your address and I’ll try and get it in the post, but it might well be a few days before I can get to a post office
It’s quite large though, shock and link are attached.

Your video showed what happened to the top part of my shock. The bits just fell out.

I’m quite impressed that the broken bolt held all the way around GT. It could have been nasty if it hadn’t made it.

have i missed something completely?

surely uou remove the bolt, (or two parts of it), slide the shock and mountings out, smack out the bush from the shock using the PROPER TOOL, replace the alloy tops hats with a steel betd through setup which will prevent the bolt failing again.
replace the bush with a hula hoop (again, using the proper tool)

thats it isnt it?

http://www.mountainbikecomponents.co.uk/items.asp?CategoryID=92&Name=Strong+Bushes

select the bush for the shock, and the bush (which has been refered to as mounting hardware so far in this thread) for the frame. measuring the gap between the two parts of the link.

strikes me as not an ideal link, as the bush isnt compressed between the two surfaces, so wont sit firmly, and can slip around?

^ Bolt is snapped in two, one half threaded into the linkage.

The broken bolt can’t go anywhere, but yes you are lucky 😯