Thorn Cycles Forum

Technical => Wheels, Tyres and Brakes => Topic started by: Team Triplet on August 17, 2004, 12:38:33 pm

Title: Ceramic Rims and brake blocks
Post by: Team Triplet on August 17, 2004, 12:38:33 pm: 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?
Title: Re: Ceramic Rims and brake blocks
Post by: colintr on August 18, 2004, 12:59:47 am: 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.
Title: Re: Ceramic Rims and brake blocks
Post by: Dave Whittle Thorn Workshop on August 22, 2004, 06:39:12 pm: 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.
Title: Re: Ceramic Rims and brake blocks
Post by: colintr on September 08, 2004, 10:01:31 pm: The kool-stops seem to work well and seem squeal free. Haven`t tested them on any long descents yet though.
Title: Re: Ceramic Rims and brake blocks
Post by: bandgap on November 01, 2004, 04:51:51 pm: 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
Title: Re: Ceramic Rims and brake blocks
Post by: John on November 17, 2004, 07:12:41 pm: 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?
Title: Re: Ceramic Rims and brake blocks
Post by: orpen on March 22, 2005, 11:29:10 pm: 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?
Title: Re: Ceramic Rims and brake blocks
Post by: ahconway on April 19, 2006, 02:28:40 pm: Okay, so what does everyone recommend for brake pads with ceramic rims? Any particular ones?
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on April 19, 2006, 02:48:32 pm: 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.
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on April 24, 2006, 12:19:58 pm: 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.
Title: Re: Ceramic Rims and brake blocks
Post by: ahconway on April 24, 2006, 12:29:03 pm: 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!
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on April 24, 2006, 01:04:43 pm: How many miles did you get out of the last set ahconway?
Title: Re: Ceramic Rims and brake blocks
Post by: ahconway on April 24, 2006, 01:38:16 pm: 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!
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on April 25, 2006, 08:42:40 am: 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.
Title: Re: Ceramic Rims and brake blocks
Post by: orpen on April 25, 2006, 12:36:50 pm: 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.)
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on May 15, 2007, 09:40:36 am: (http://i139.photobucket.com/albums/q313/stutho/map2.gif)Reminded myself yesterday why I have got ceramic rims. I was descending the steep hill indicated (speed ~40mph) when at about the worst possible moment a man walked out from behind a hedge (without looking) dragging a large tarpaulin! There is no way my other bike would have stopped in time and there was no room to swerve - due to the tarpaulin. AS it was I braked EXTREAMLY hard front and rear (locking up and releasing the rear twice). Finally I came to a stop about 3 foot short! The guy only saw me after I stopped - I should of shouted a warning but I was to busy controlling the bike at the time.

For the record my bike is set up with Mavic 717 ceramics, Coolstop salmon front (with a booster) and Coolstop green rear. Both callipers are Avid Ultimates being puled by dia-compe 287V drop levers. Neither brake makes any noise and brake pad ware is the now the same as with non-ceramic rims.
Title: Re: Ceramic Rims and brake blocks
Post by: lewisnoble on May 15, 2007, 11:35:19 am: Phew!! Are you sure you don't have ABS as well??
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on May 15, 2007, 12:05:31 pm: No but I do have brown pants!
Title: Re: Ceramic Rims and brake blocks
Post by: ahconway on July 05, 2007, 01:31:02 am: So I was changing to my summer tyres today, and I was horrified to see the condition of my rear ceramic rim.

The sides are spotty, and it looks like the finish has "flaked off" as others in this threat have mentioned.

No problem on the front rim, though. I've been using Shimano pads for ceramic rims on both.

What's going on here? Is this something I need to be concerned about?
Title: Re: Ceramic Rims and brake blocks
Post by: mountaincarrot on July 17, 2007, 04:38:48 pm: I think they just wear out!

I commute (XC riding only)in sandy Surrey hills and got through a pair of standard Mavic XC rims in about 2000 miles. I then changed to some heavy duty DH Ceramic Mavic rims (Can't remember the number). The ceramic on the rear had it's first holes in after 2000 miles, and now has largely disappeared on the rear rim, and I'm down to wearing out the aluminium. The front is still 50% ceramic coated. This is after ~5000 miles with just a few very short dabs of the brakes each day.

The Shimano ceramic pads did the initial damage (pockmarks after 2000 miles). Since themn I've run ordinary Koolstops on them. I can't say the wear on the rims is any worse, but they don't stop as well as the new set-up with ceramic pads.

I recon I'll get 5000 miles from the ceramic rims versus 2000 from ordinary. (That's with XT parallel-action brakes).
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on July 17, 2007, 05:12:17 pm: Hi Ahconway,

Sorry to here you are having problems with you rims. The problem of the ceramic coating wearing off (especially on Mavics) has being reported by a number of people on the net. People using Shimano pads seam to be particularly vulnerable - I would switch the pads out straight away if I were you.

As a data point I have currently got about 7000 miles on my ceramic rims the front rim looks almost new and the rear looks older but has no sign of ceramic ware (I use Koolstop salmon pads).
Title: Re: Ceramic Rims and brake blocks
Post by: ahconway on July 18, 2007, 02:53:04 am: Geez!

Thanks Stutho. Exactly which pads do you use? There are lots of salmons by Kool Stop!
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on July 18, 2007, 09:00:44 am: I have used salmon Thinlines but currently I use Salmon V-Brake inserts. You probably know this already but the Salmon colour is an all weather compound. I have also used the Green, ceramic compound, which I did not find as good as the salmon.

thinline (not salmon)
V-Brake inserts (not salmon)

[img=left]http://www.koolstop.com/brakes/thinline.jpg[/img=left][img=right]http://www.koolstop.com/brakes/V-Dual2.jpg[/img=right]

Clearly I have V brakes!!
Title: Re: Ceramic Rims and brake blocks
Post by: Magnus Thor on July 19, 2007, 09:53:16 pm: Strange! I've been using ceramic rims for the last 4 years, Mavic 721 XC. I think I have clocked up around 15000km by now and a lot of that is winter riding, with all the sand, salt and grit that entails. I started using standard brake blocks, but switched over to ceramic specific after approx. 2000km.
So far the rims look pristine...

Magnus Thor
Iceland
Title: Re: Ceramic Rims and brake blocks
Post by: Magnus Thor on July 19, 2007, 09:56:59 pm: Strange! I've been using ceramic rims for the last 4 years, Mavic 721 XC. I think I have clocked up around 15000km by now and a lot of that is winter riding, with all the sand, salt and grit that entails. I started using standard brake blocks, but switched over to ceramic specific after approx. 2000km.
So far the rims look pristine...

Magnus Thor
Iceland
Title: Re: Ceramic Rims and brake blocks
Post by: avdave on October 11, 2007, 09:39:23 pm: I've just ordered avid ceramic pads for my Catalyst, I'll let you know how i get on with them. The original pads have lasted over a year but there are'nt many hills on my commute. I've also worn the rear down faster than the front but I think thats because I tend to use it as a drag to regulate speed while changing gear with my right hand and using the front brake when I acctually need to stop. I have thought about reversing the brake levers so that I'm not controlling what should be the primary brake and the gear change with one hand. Has anyone done this?
Title: Re: Ceramic Rims and brake blocks
Post by: pdamm on October 11, 2007, 10:22:42 pm: I have the shifter on the left had side so my right can use the front brake. Swaping the braks around would also achieve one hand for the important front brake and the other for the shifter. I didn't do it that way in case I rode somebody else's bike and got confused when I really needed the brakes.
Title: Re: Ceramic Rims and brake blocks
Post by: avdave on October 12, 2007, 01:40:23 pm: Thats a good point pdamm, worth considering as an option.
Title: Re: Ceramic Rims and brake blocks
Post by: stutho on October 12, 2007, 09:22:09 pm: On my RST (with drops) the shifter is on the left for the exact same reason. On the wife’s RT (flat bar) the shifter is on the right as you don’t need to move your hand from the bar/brake to shift there seems little point in mounting this one on the left.
Title: Re: Ceramic Rims and brake blocks
Post by: RJC on January 19, 2009, 02:16:03 pm: If using Rigida CSS rims another option is Koolstop CSS ceramic compound.
I guess this is different to their standard green ceramic compound. When Rigida
developed the CSS coating Koolstop developed a brake compound in collaboration
with Rigida. I don't know why Koolstop don't mention it on their website.

Available in cantilever, V-brake & road brake style blocks.
In the UK you will probably need to contact the importer (Amba-Marketing)
who should be able to point you to a shop that can order the pads.
I believe the price should be similar to Koolstop dual compound.

[Edit] SJS now have these KoolStop CSS blocks in V-brake and post mount style.
The latter could be useful for cantilevers since SwissStop blue is only available
in v-brake style.

Picture below - you might need to be logged in to see.
Title: Re: Ceramic Rims and brake blocks
Post by: JohnWay on February 18, 2009, 04:20:07 pm: The blocks currently being reccomended by and available from SJS/Thorn for use with Rigida CSS rims are made by Swissstop and is their blue compound Carbide specific pad.

I'ts certainly available in a slip in cartridge format for V brakes, don't know what others available. I've got them fitted to XTR V brakes with Rigida Grizzly rims on my new Sherpa which I collected yesterday.

Will let you know when I have had chance to try them in anger (when I'm back at work next week, my commute has a couple of sections with 20% gradients on it) they must work better than the old xt cantilever setup I've been using with various pads over the last 20 years on my Mercian!
Title: Re: Ceramic Rims and brake blocks
Post by: geocycle on February 18, 2009, 08:33:40 pm: I've used the carbide rims and koolstop blue compound blocks since September. I'd say they were as good as standard blocks in the dry and better in the wet. There is still plenty of wear left in the blocks after some 1500+ winter miles.
Title: Re: Ceramic Rims and brake blocks
Post by: davefife on May 27, 2009, 12:29:37 pm: http://www.thorncycles.co.uk/forums/index.php?topic=1698.0
just posted some relevant comment in another topic