O rings. How flipping hard can it be?

**Disco Dan** · 8th December 2012, 21:09

Long story short:

Brake calipers need new o-rings. Emailed just about every bike shop in New Zealand - They all quoted me about $14 PER ring. Basically about $200 for 16 little rubber o-rings.

Ebay - nothing. At least not any cheaper. Even rebuild kits.
Trademe - nothing.
Amazon - nothing.

Cheapest place I can find is partsmonster.co.nz but never flipping heard of them and their website is a bit budget. On the plus side - seem to basically be a complete online microfiche of just about every bike, complete with part numbers. AND... AND... they reckon they can get me the parts inside a week - as opposed to 3-4 weeks that the bike shops quoted me.

Now I figure these little suckers form the very essence of a braking system and if they are wrong would mean that Disco really is dead. I'm guessing they would have to be exact size, material and behave the very same way as OEM if I get a pack down the hardware store - so not really keen on doing that.

Oh and that price is PLUS GST and there is a shipping on top.

Is there a better way??? Have I actually made it possible to "get lost" on the internet and missed the obvious? Yes I tried google, that is how I found all the shops and Partsmonster.co.nz anyone actually used them?

**FJRider** · 8th December 2012, 21:19

Go into any engineering supplies shop and ask. Have outside diameter and thickness (or original one) with you.

**AllanB** · 8th December 2012, 21:23

ZX1100? If so get on one of the Zed forums and search. bet there is a linky.

**pete376403** · 8th December 2012, 21:25

If the seals you are referring to are the brake piston seals - (unless things have changed since I learned about such things) they are not circular cross-section (ie not your common or garden O ring. Brake seals are square in cross-section, as the piston moves out (applying brakes) the ring twists. Untwisting is what retracts the piston when you release the brake. As the pads wear, once the seal has reached maximum twist, the piston slides through, but the untwisting will still retract the piston. This is how disc brakes self-adjust.

These are special items so you're not going to find them at Mitre10. Considering what they do, and how important they are, they are cheap at the price.

**Disco Dan** · 8th December 2012, 21:27

ooooooooooh ring.

**bogan** · 8th December 2012, 21:27

Originally Posted by FJRider

Go into any engineering supplies shop and ask. Have outside diameter and thickness (or original one) with you.

Do not do this!

Brake fluid degrades a lot of materials very quickly (why you be careful not to get any on your paint, or hands), so you must be sure the o-ring rubber is brake fluid safe. In addition all the brake fluid o-rings I've seen are actually square section.

Still 200 for a set sounds a bit expensive, have you tried places like wemoto?

**Disco Dan** · 8th December 2012, 21:30

Originally Posted by bogan

Do not do this!

Okay.

Originally Posted by bogan

Brake fluid degrades a lot of materials very quickly (why you be careful not to get any on your paint, or hands), so you must be sure the o-ring rubber is brake fluid safe. In addition all the brake fluid o-rings I've seen are actually square section.

Still 200 for a set sounds a bit expensive, have you tried places like wemoto?

Wemoto - basically the same price but with more expensive shipping.

**Madness** · 8th December 2012, 21:31

http://www.bitzforbikes.co.uk/Four_F...1691-224-.html

Pete's right. Looks like a mix of square section seals & o-rings. PM Imdying on here, he knows brakes.

How do the pistons look?

**Disco Dan** · 8th December 2012, 21:31

Originally Posted by pete376403

If the seals you are referring to are the brake piston seals - (unless things have changed since I learned about such things) they are not circular cross-section (ie not your common or garden O ring. Brake seals are square in cross-section, as the piston moves out (applying brakes) the ring twists. Untwisting is what retracts the piston when you release the brake. As the pads wear, once the seal has reached maximum twist, the piston slides through, but the untwisting will still retract the piston. This is how disc brakes self-adjust.

These are special items so you're not going to find them at Mitre10. Considering what they do, and how important they are, they are cheap at the price.

Square O's you say? Interesting! So defo OEM then.

**Disco Dan** · 8th December 2012, 21:37

Originally Posted by Madness

http://www.bitzforbikes.co.uk/Four_F...1691-224-.html

FJ's right, looks like a mix of square section seals & o-rings. PM Imdying on here, he knows brakes.

Crikey - that site is interesting, "front left" and "front right" kits? They are different?

**Madness** · 8th December 2012, 21:39

Originally Posted by Disco Dan

Crikey - that site is interesting, "front left" and "front right" kits? They are different?

Unlikely I'd imagine.

PM Imdying.

**Disco Dan** · 8th December 2012, 21:47

oh and that site.... dangerous. So much stuff to explore and no flipping idea how much it costs in Hobbit Dollars (without working it out!).

**Disco Dan** · 8th December 2012, 21:57

Thanks for the replies though. Feel a lot better about spending that much on what I thought were just basically fancy tap washers I could get at Mitre10.

Well if I'm not posting here in a week or two... well then I put them in wrong.

**sidecar bob** · 9th December 2012, 06:59

Call Extreme Auto Parts in 2nd Ave Tauranga & talk to Dean or Robert Ph 07 5788175.
They are a leading importer of brake components.
I frequently purchase caliper kits off them for the fleet race bikes i maintain & never pay more than about $3.00 per seal.