open pro ceramic rims - wet weather

moonie

I have been having trouble with my rear brakes on open pro ceramic rims, I've tried 3 types of pad all with the same result. In the dry the brakes are outstanding, but in the wet they initially have no effect at all, then vaguely work slowing me down, eventually (200 to 400metres or so) they really work, almost always locking up the rear wheel. So long as I keep the pads just rubbing they continue to work as if dry, but as soon as they get wet, the whole process starts again. I sort of lived with this in the 3 months I've had them, now I want to sort the problem out, anyone any similar experience? Or ideas as what i can do (without changing pads, the last ones were swiss stop ceramics at £20 and are no better than any others)
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rafletcher

Thats the experience of most people with ceramic rims I'm afraid. I think some use special cork blocks to help in the wet.

moonie

Thanks RAFletcher for the reply Cork blocks? where from? I never have this problem on the front wheel any ideas why?

OnTow

Mavic make some blocks. No idea where you can get them though - try the people who sell the rims, such as Sigma Sport.
Condor and a few other places sell Swissstops - The GHPs are very good on normal rims. Not sure if the yellow carbon-specific blocks would work better - maybe an email to them would confirm. (swissstop.com).

Koolstop do a ceramic specific block - Normal Koolstops get good reviews on the forums:
http://www.koolstop.com/brakes/Ceramic.html

Monty Dog

I would avoid using cork blocks on ceramic rims otherwise you'd have no blocks in no time - cork blocks are used on carbon rims where heat build up is an issue. I believe the Mavic bocks are just repackaged Swiss Stops. Perhaps you need to look at your braking style - apply the brake to wipe the rim of water an then apply the brake normally - works far better than riding the brakes IME.

Eurostar

Oh dear, that's a bit glum. I was thinking of getting OP ceramics. Have you asked at anothercyclingforum? There are some audaxers there with these rims.

Just done a search for this at weightweenies and there doesn't seem to be a wonder product. Swissstop greens are quite highly rated! Have you tried Clarks? http://tinyurl.com/2ps4o7 They look too cheap to be good.

As for carbon rims, Swissstop yellows are said by several weightweenies to be a little better than the greens. Some people say the very best ones are the Lightweight branded ones (which are grey.). They are made by Swissstop. But they cost £33 for 4!

I tried cork pads on carbon rims (Corima red ones) but the wear rate in the dry was astonishing and they were useless in the wet. If I hadn't thrown them away you could try them for free.

lfoggy

I've got Mavic ceramic rims on my Audax bike and I use Avid ceramic specific brake pads. Ive found the braking to be generally better in both wet and dry to my previous setup of aluminium rims and standard Avid pads. I've certainly not had the problem you mention in the wet.

Eurostar

So you must have cantilever or V brakes? Just had a look at the Avid site and they don't seem to do sidepulls.

But SRAM is the same company - they do sidepulls. Can't seem to find any info about spare brake pads for them though

lfoggy

Yes, Ive got Mavic XC717 ceramic rims and Avid Shorty cantilever brakes. There is no reason why you couldn't buy a set of Avid shoes and ceramic specific inserts and use them on a sidepull brake set up though.

OnTow

Eurostar wrote:

Oh dear, that's a bit glum. I was thinking of getting OP ceramics.....

Why not just go for one version lower than the ceramics - the ones with just the CD technology? They're half the price, and seem fine to me.

moonie

Thanks for the input, i have tried varying my braking style, pulling the brake as hard as i can has little effect in the wet, and i am using swisstop green blocks, they are no better than any other, including bog standard cheap non-ceramic blocks. there must be a reason for this as the front brake is astonishingly good (so don't be glum eurostar, when they work, they WORK).

I am hoping that the rim is contaminated with oil or something and will be degreasing them this weekend, I'll let you know. I really do not think it is down to the blocks anymore as i have just tried the front ones on the back, soaked the whole thing and have the same effect. Maybe i have a duff rim? (or i enjoy clutching at straws)

maddog 2

I use Avid ceramic blocks on mine, and wet braking is excellent

(I use Vs though)