Ceramic Rims and brake blocks

[Team Triplet]

I have ceramic rims on my new baby, running LX V brakes with normal brake blocks.  I notice that you can get brake blocks for Alumunium or Ceramic rims.  I assume that the blocks supplied are for alumunium rims.

Q. is the use of brake block for Al rims determental to Ceramic rims?

[colintr]

My understanding is that ceramic rims will wear out normal blocks in no time flat but the rims will not be damaged by their use. I`ve recently taken delivery of a Raven adventure tour and found the brakes (XTR V brakes/normal blocks) fine in normal use but tend to fade on long steep descents. Have just replaced blocks with Kool stop green chromium blocks for ceramic rims only have not tested them yet. Will let you know how they perform.

[Dave Whittle Thorn Workshop]

With standard rubber blocks the ceramic rim will absorb the heat generated and caus the ceramic to flate off.  Sintered compound blocks designed for ceramic brake absorb the heat themselves taking it away from the rim.  This only happens on long decents and some people use standard rubber compound brakes regardless as they stop better.

[colintr]

The kool-stops seem to work well and seem squeal free. Haven`t tested them on any long descents yet though.

[bandgap]

I have had lots of ceramic rims with lots of brake blocks.
Mostly Mavic rims.
Except for one Sun 'ceramic' rim that seemed more like anodised than ceramic and an FIR ceramic rim of dubious quality.  

Observations are:

Initially blocks wear fast, but always settles down to same or better than anodised or plain aluminium rims.

Once 'run-in', dry performance excellent. Braking with ceramic worse than plain aluminium in the wet, but not much.
 - Except with standard Magura hydralic rim brakes blocks and ceramic where wet weather performance is appalling. A change to 'grey' blocks helps a lot, but is not ideal.

The rear ceramic-equipped brake of my commuter with V-brakes is rubbish in the wet - probably down to oil contamination from the filthy chain.

In short, and after several long tours and some massive camping-loaded descents, I would always go for ceramic as they last so much longer and drawbacks, if any, are slight.
They cost much more, but this is somewhat swallowed by the cost of wheel building.

Steve

[John]

The ceramic flakes off even with ceramic specific blocks if you get the ceramic hot enough. The pad wear rate is then high on the flaky surface. One of the advantages of running ceramics is that the rim is insulated from braking heat and the tyre less likely to come off Or the wheel buckle. The rim still gets too hot for my liking.

Rigida's Carbide Super Sonic is a lot more resistant if you can find a suitable rim size but rapid pad wear is a problem until they wear a bit. Ceramic pads are a must on the Rigidas unless you're deaf.

Ever thought of running discs?

[orpen]

This info. on ceramic rims is a bit off putting.
Having worn through three pairs of mormal rimes off road (Winter riding in the muddy Cotswolds doesn't help) I decided to go ceramic. (unfortunately my Pace forks and Airborne Ti frame have financially locked me in to V brakes  - Avid arch rivals. To go disc I'd have to start from scratch and the cost of matching the feel of my current frame & fork combo is out of reach currently.)

I'd suspected the ceramics weren't stoppoing me any quicker than normal rims, despite the leaflet with the Mavic 517 rims very clealy saying stropping power is better. However I'm not sure whether I've got the ceramic specific blocks, so I'll check this - but from what's been said, these might be worse (just better on keeping the rim cool) and in the wet you're telling me it's worse still.

Am I going to be risking my neck trying to keep up on the tricky trails with chums who are (very nearly) disc braked to man (& woman)?

I had thought a set of Magura HS33's might be the answer, but from the discussion so far I'm not so sure.  Can anyone point me in the right direction please?

[ahconway]

Okay, so what does everyone recommend for brake pads with ceramic rims? Any particular ones?

[stutho]

I have being using Kool stop salmon (A non-ceramic block) It stop great but does squeal with my Avid SL brakes. (Toe in, cleaning, talc, toe out, brake booster - nothing has stopped the squeal. I am about to try Kool stop green (a ceramic block) I will let you know.

[stutho]

I have been running Koolstop salmon for about 3 months stopped great in the wet or dry but made a racket doing it.  In 3 months the pads had almost worn down to the holders.  The rate of ware decreased substantially during this time.

On the weekend I fitted Koolstop green.  They are much quieter than the salmon, however they don't seam to stop me so quickly and more force is required at the lever.  They haven’t had chance to bed in yet so I will report back if they get any better.

[ahconway]

Interesting. I ordered some new pads today. But still mildly confused and not wanting to deal with squealing, I got bog standard Deore ones - which SJSC recommends anyhow. I didn't have any performance issues with my original pads, so I suspect this will work fine. I'd been operating under a mistaken assumption that purely because ceramic-specific pads exist, I'd be doing myself (and my rims) a disservice by not using them. I guess that's marketing for you...

Caveat emptor!

[stutho]

How many miles did you get out of the last set ahconway?

[ahconway]

quote:Originally posted by stutho

How many miles did you get out of the last set ahconway?

About 1100 - though the rear set wore out before the front. I would have expected it to be the other way round... probably doesn't say much for my braking skills!

[stutho]

I got about 800 miles out of the Koolstops Salmon.  I live in a very hilly part of the country and my brakes get a lot of use.  The first 250 miles did 2/3 of the ware (new ceramic rims).  My rear blocks still look like new.  

The Koolstop Green pads have started to bed in and are stopping a bit quicker.  They are still not as good as the Salmons.

[orpen]

I did eventually buy some Magura 33's, the new type with the booster bar which at first looks too thin until you realise that it works by being in tension, unlike the usual horseshoe shaped boosters which work by resisting bending.

 I need a booster as my frame is titanium and the seat stays flex even with boosters. Neverthelss I'm  sure this isn't the full explanation for the disappointing performance I'm getting fom Magrua's green pads and ceramic rims expecially in the wet. They don't seem any better' and maybe worse' than Avid Arch Rivals well set up on normal alloy rims. (I think green are the magura cermaid pads - I'm sure someone will tell me if there are better ones.)