Rear brake pad sheared off?

slogfester · Post by **slogfester** » 19 Jan 2014 17:47

During todays B run, some may have noticed that I started to fiddle with my back brake just after leaving Evesham. I had suddenly lost 80% of braking power on the rear. At first I thought someone was playing silly billies at the café and had flipped the quick release on the (Ultegra) rear brake because there was suddenly a lot of travel in the lever. That was not the case so I concluded that the cable must have really stretched due to the wet conditions. I turned the barrel a few times (while riding), but it wasn't much good for the rest of the ride. The brakes have only done 1800 km from new and I keep rims and pads as clean as possible for this time of year. Closer inspection at home revealed that the rear right pad (Shimano)appears to have sheared off!

20140119_154853 by Slogfester, on Flickr

Compare with the front pads (same age), barely any wear at all:

20140119_155003 by Slogfester, on Flickr

There are a couple of other pics here (at the bottom), for those interested:

http://flic.kr/s/aHsjqKzWpY

Normal wear? I aint no hand-on-the-brake cruiser!
The left rear pad is worn down more than the fronts, but nothing like the right rear which just looks like it sheared off. Possibly because it appears to have been incorrectly aligned (by Echelon) when the bike was built?

Coincidently the bike is due for its free first service with Echelon on Tuesday, so I shall see.
Anyone recommend replacement pads for the winter roads?

gmac · Post by **gmac** » 19 Jan 2014 18:30

Kool stop salmon http://www.wiggle.co.uk/kool-stop-dura2 ... e-inserts/

Gary

Post by **CakeStop** » 19 Jan 2014 19:29

gmac wrote:Kool stop salmon http://www.wiggle.co.uk/kool-stop-dura2 ... e-inserts/

Gary

Gary knows best.

Shimano are rim eaters.

Philip Whiteman · Post by **Philip Whiteman** » 19 Jan 2014 19:39

CakeStop wrote:
gmac wrote:Kool stop salmon http://www.wiggle.co.uk/kool-stop-dura2 ... e-inserts/

Gary
Gary knows best.

Shimano are rim eaters.

+1

AlanW · Post by **AlanW** » 19 Jan 2014 19:43

Philip Whiteman wrote:
CakeStop wrote:
gmac wrote:Kool stop salmon http://www.wiggle.co.uk/kool-stop-dura2 ... e-inserts/

Gary
Gary knows best.

Shimano are rim eaters.
+1

+1 Salmon ones in the front and black ones in the rear.

Philip Whiteman · Post by **Philip Whiteman** » 19 Jan 2014 19:47

It may be the picture but the un-damaged LH hanger appears to fitted the wrong way round. The gap for the insert should be rear facing. There is no lip on the underside of the LH hanger, is this facing upwards? The RH hanger lip is clearly downwards.

Philip Whiteman wrote:
CakeStop wrote:
gmac wrote:Kool stop salmon http://www.wiggle.co.uk/kool-stop-dura2 ... e-inserts/

Gary
Gary knows best.

Shimano are rim eaters.
+1

AlanW · Post by **AlanW** » 19 Jan 2014 20:39

It also looks like they are one piece brake blocks? If that is the case then you will also need to buy the brake block carriers in order to fit the KoolStop brake blocks.

Just a thought, but is the caliper pulling equally on both sides of the rim?

LINK Here you go everything that you need plus dual compound blocks.

Philip Whiteman · Post by **Philip Whiteman** » 20 Jan 2014 09:25

AlanW wrote:It also looks like they are one piece brake blocks? If that is the case then you will also need to buy the brake block carriers in order to fit the KoolStop brake blocks.

Just a thought, but is the caliper pulling equally on both sides of the rim?

LINK Here you go everything that you need plus dual compound blocks.

Aren't the mono-blocks two pieces of rubber bonded together? In which case, the bond must have failed. Something I have never heard of before in terms of brake blocks.

slogfester · Post by **slogfester** » 20 Jan 2014 09:57

Thanks for observations, comments and recommendations chaps.

Closer 2nd look in daylight reveals that the Ultegra 6800 brakes are indeed one-piece. They have been fitted the correct way (except perhaps the previously noted slight non-alignment on the RH). They are working perfectly, i.e. nice equal progressive pull. (The new 6800 are dual pivot like the DA, and I've found them to be very powerful with a great feel)

The 1-piece pads are cheap at 6.50 a pair:

http://www.wiggle.co.uk/shimano-ultegra ... ke-blocks/

and blurb says they have some design that saves the rim if they are allowed to wear down too much? Perhaps 2 types of rubber bonded together as Phil suggests?

I conclude that the RH side block has sheared off given that it happened so suddenly.

AlanW · Post by **AlanW** » 20 Jan 2014 15:18

slogfester wrote: The 1-piece pads are cheap at 6.50 a pair:

http://www.wiggle.co.uk/shimano-ultegra ... ke-blocks/

and blurb says they have some design that saves the rim if they are allowed to wear down too much? Perhaps 2 types of rubber bonded together as Phil suggests?

I conclude that the RH side block has sheared off given that it happened so suddenly.

No matter how cheap they are and no matter what bullshit Shimano spin on them, DONT replace with the same! Whats more, the "rim saver" as they like to call it, is that little black rubber grommet on the inside of the holder.

slogfester · Post by **slogfester** » 20 Jan 2014 16:48

Don't worry Alan, I wont. Especially after what has happened.

Its funny how Shimano produces such fantastic precision engineering and then lets itself down with some odd bits and bobs. Their chain oil (bought in desperation while on tour) is the worst stuff I have ever used.

Thanks

Dave Cox · Post by **Dave Cox** » 20 Jan 2014 17:19

Gary Fisher reckoned when he spoke at Bike Lounge last month that Shimano are great on metallurgy and invest a lot in research! Perhaps they just buy cheap rubber in knowing that we all like Koolstop??

PatBoySlim · Post by **PatBoySlim** » 25 Jan 2014 16:52

+1 for Koolstop,
I took the shimano off on advice of Mr Weaver after the night ride we did, even in the dark he knew I was using shimano from the sound.
On inspection after removal, sure enough , metal filings in the pad.

AlanW · Post by **AlanW** » 25 Jan 2014 17:35

PatBoySlim wrote: after the night ride we did,

And what a great ride it was to, I really enjoyed, we MUST do it again this year?

Pedlo Mudguardo · Post by **Pedlo Mudguardo** » 25 Jan 2014 20:24

I'm up for a night ride.

AlanW · Post by **AlanW** » 25 Jan 2014 20:29

Pedlo Mudguardo wrote:I'm up for a night ride.

It would be interesting to see how much interest we would get if we did another one. I'll start a new thread on the MB to gauge interest.

slogfester · Post by **slogfester** » 26 Jan 2014 18:20

Just to follow-up and complete this thread. When the brakes were dismantled and inspected in bike shop, the conclusion was that the pad had not sheared off. Rather the tiny mis-allignment had led to a ridge building up on the block that must have suddenly given way.
I did not have time to source koolstop, and Echelon don't stock them. So I have ended up with Swissstop black.