You are hereForums / By Discipline / Mountain (off road) / MTB Gear / sandpaper + disc brakes = ??
sandpaper + disc brakes = ??
NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.
Hi all,
i recently purchased Avid Juicy 7 Carbons with new 8" rotors and i broke them in slowly never really slamming on the brakes.
I was told that they may have 'baked' the pads, as i should have been braking hard to break in the discs and pads.
It was suggested that i take out the pads and sand them down a bit with a find grain sandpaper and do the same to the discs.
Is this a good/bad thing to do?
anybody else have experience in this area?
Totally different question as well: which pads are best: organic, metallic or ceramic?
thanks
- Login to post comments
- Bookmark & share
Tags
I love questions like this. First up, brake pad types.
Organic; Also referred to as Resin. These are usually a cheaper type but only as they are cheaper to produce. They are not inferior in performance. They tend to heat up less and therefore the entire system is less prone to problems associated with high temperatures such as fade. Use these pads if you are on the brakes a lot, such as long downhill sections. Also good for commuting in heavy traffic when brake contol and low speed manouevering is common. The negative is they won't be very long lasting but the lower cost should compensate for this. A good all round pad.
Metallic; This is the same as sintered and refers to a large content of metal in the pad compound, usually and mostly copper. These pads heat up very quickly and stay hot and work best with floating rotors or even better, vented rotors. These are for experienced and good riders only as the idea is to brake late and apply an almighty fistful of braking force to slow oneself and then tip into a turn or ride that drop or what have you. Remember that a rider has least control whilst under brakes. So one must do all their braking, then get those wheels turning again and free up the suspension for the next section. Use these pads if you can ride like this, or aim to do so. They have a long life relevant to their output. And can be dear.
Ceramic; This only refers to V, canti and dual pivot type brakes and must be used with a ceramic rim to work correctly. The rims are a little fragile and are dearer than conventional rims and if the terrain is rocky then one probably should avoid.
This is how I bed in pads. It's the same for a complete new kit, or simply new pads popped into your existing system.
1. Ride normally. Avoid dragging brakes for long periods. Do about ten kays.
2. Put your reach adjust into preferred spot. Check caliper is centered over rotor and adjust if required.
3. Ride again for about ten more kays. Repeat step two.
4. Keep on doing this until they feel good. After about forty kays start doing some hard stops.
5. Keep an eye on caliper position and reach position and adjust pad contact if your brake has that feature.
6. After forty kays you'll be able to brake with supreme confidence with sintered pads and sooner with organic pads.
That's it. Not to hard at really....
thanks for that.
i'd still like to know about 'baked' pads and if sanding pads and discs will help with brake power/performance. is it possible to have 'baked' the pads by feathering too much during break in period?
are there any visual signs of 'baked' pads?
If you drag your brakes a lot you can glaze them up (ie bake the outside hard)but it takes a bit of doing with disc pads. Giving the a light file or sand should remove the outer crust and rough them up again.
Sanding the disc itself shouldn't be needed unless you've done a very good job at baking them.
When rebedding them try and do short hard bursts of braking, hard on/off in the car park (just don't go OTBs). Do this about a dozen times at least to bed them.
As for visual signs of a glazed pad. Yeah it will look smooth and little shiny compare to one not glazed
I apologise for not addressing this. I fully endorse what flynny recommends. Just be certain they are indeed glazed as if you feel they are not performing then they may simply not be bedded in yet.
Don't touch the disc. They are not like motorcycle or car rotors and won't benefit from a grind. When they're knackered, it's off to the shops for you.
And also, if you were to go OTB whilst carrying out flynnys' car park remedy, then your pads wouldn't be concerned one little bit!
yeh i can vouch for ceramics, i got some ceramic pads for my hayes 8" and they shat all over the sintered ones that came stock and the generic sintereds too, using organic now as well on codes and they are very good too, i hear also they dont last that long..
personally ive sand-papered pads before that have been "cooked" or super shiny and slippery, and it made them heaps better, can remove funny noises too if you experience that