Anyone know anything about disc brakes?

16,64stones here (had to google it to be able to understand how many stones you need to express 106kg of weight). And going down 10-15% descents, (and up) with a ~90kg rider + 16kg of bike and equipment. Front 160 for sure, but back... 140 is more than enough (with mech disc brakes), even under snow and wet conditions north-alike... but technique is also important. In the pictures, there is no water (2liters ~ 2kgs) or food in the bike... shoes and helmet count too

2 Attachments

ahh i see i see. fair play. slx's are great. i assume they are more powerful than the rs685

also if anyone wants a brand new rs685 caliper I have one spare (warranty replacement) - £35 shipped

does anyone have a pair of TRP Spyre calipers for sale before I buy some new?

thanks for that. interesting. unsure what to do. don't fancy buying loads of different discs, as they don't hold much value second hand. i would like to blame the gappyness of the rotors for the slightly underwhelming stopping power

i would like to blame the gappyness of the rotors for the slightly underwhelming stopping power

Are they they Shimano rotors? If not, FFS, get the Shimano rotors!

yep

I was worried, a lot, while building the bike, even more when the Kinesis 4S Disc frameset that was announced to be 160 compatible at the rear... came out to be a lie / design fail... But even with mech calipers its ok, haven't crashed yet :D. I use TRP normal discs, but got a 140 + 160mm rotors with dissipation for free and tried them with nice results http://www.reverse-components.com/en/products/discrotor-aircon-%C3%B8140mm

If you couldn't lock the back wheel, I reckon a rebleed is in the card, as it should feel very sharp and immediate.

I'm 93kg with R685s, 140mm rotor at the back (avid hsx) and that'll lock easily.

so the first caliper exploded, I then replaced this with a new one while the warranty claim went under way. the mechanic at muddock installed the new caliper and bled it - huge improvement, exactly how a disc should feel. it still isn't hugely hugely powerful though, the mechanic agrees and says the discs are stupid and I should buy shimano ones. maybe a rebleed is still necessary though, will do it myself. i take it the shimano brake fluid for road an mtb is the same

@Howard they aren't but the shimano rotors in 140 only come in centrelock so I am stuck

those discs look fucking cool

Well I can't say if the cooling parts really work, haven't even seen any reports on the shimano ice-tech rotors... Superstar components also sells the same model under a different brand http://www.superstarcomponents.com/en/alpine-evo-rotor-arctic-cooling-fins.htm but they don't do less than 160, the only option I know to get a 140mm rotor with cooling parts and 6-bolts is the Discrotor Aircon. Only thing to know is that the cooling parts are not totally fixed, they move a bit, so you can hear sometimes some metal-hitting-metal but at high speeds you don't even notice.

I'm pretty sure the Ultegra-level Hydro brifters can come with either the new flatmount caliper or a postmount M785 caliper, so I would assume the road and mtb ones are all compatible.

metal-hitting-metal? please elaborate haha

if this is true I would rather run SLX calipers

If the pistons are the same diameter, there should be no problem.

even more interesting...

I still can't decide what to do really. try some different 140mm discs and rebleed the rear before jumping to 160?

The noise at slow speed is a know thing with floating rotors - the mounting bit is alu, the braking is steel, with a bit of space in between to expand under heavy braking to prevent warping hence there's some lateral movement between them.

Sorry, sometimes my english is not quite good, a video is worth a thousand words:

https://www.youtube.com/watch?v=EV9-AujwJmA

oh i see! yeah no problem

Just want to say that my previously a bit floppy brakes are now 'high and hard' - thanks guys.

Amazing what a bit of supposedly taboo pumping can achieve!

after riding mine today I am convinced its the rotors. the brakes work really well, such sharp action

Any recommendations for decent organic/resin pads for TRP Spyres?

I spy these which are expensive: http://www.chainreactioncycles.com/swissstop-shimano-deore-m515-m525-tektro-disc-pads/rp-prod86215 and these which are cheap: https://www.evanscycles.com/fwe-shimano-deore-m515-tektro-auriga-trp-spyre-hylex-resin-disc-brake-pads-EV266100

Any decent half way houses between those?

SwissStop have worked great for me with the Spyres, money well spent

These are my favourite: http://www.chainreactioncycles.com/shimano-slx-alfine-g01s-disc-brake-pads/rp-prod92721

Decently priced original spare parts, what's not to like?