Hi all,

I took advantage of the CRC offers to convert my front end from V’s to disc. I bought a new front wheel and Avid BB7 185mm disc brake. I’ve been out for a test ride and to bed it in and it’s all set as per the Avid website, video and instructions.

The disc noise has gone except for under the hardest braking but I have got a few questions. I have never ridden a bike with discs so don’t know if this is normal:

1)There is a noise when braking that sounds like the groves passing the pads. A sort of brrrrrrr. Only quiet and more of a wind noise rather than a mechanical noise.

2) I still have the V brake on the rear. This is very quick to bite, and bights hard with minimal lever travel (dry). The disc has a lot more lever travel and doesn’t offer the same bite of a V brake. Obviously this is in the dry. I hope it’ll be a massive improvement in the wet mud. I can’t see anyway of adjusting the cable pull without the pads rubbing the disc. I have Speed Dial 7 levers and even with those adjusted correctly (for minimal modulation) the lever pulls right back to the bar without locking the front wheel up.

3) The only time I can lock the front wheel is on a steep downhill with wet cobbles. With V’s I had to be a lot more careful not to lock-up when braking hard on the front.

I’ll be hitting the trails on Sunday, but wondered if there was anything I needed to look at before then to increase the bite, or is this just normal? If I could get less lever travel I’d be happier to be honest.

Cheers, Martin

Not sure about the lever setup, but with ANY disc brake, you need to get the pads quite hot to bed them in properly.
I usually carry out repeated heavy stops from 20mph on a steep hill, a good 5-10 times will get them nice and toasty.

The disc has a lot more lever travel

you need to ‘preload’ by pulling the arm forward before tightening the cable. bb7s are quite sensitive to this, once sorted they’ll be great.

Bigyinn:

I wouldn’t have got them that hot that many times I don’t think, maybe on one hill.

I’ll give that a go on Sunday, thanks. Guess I’ll need to dial the pads in again after that. Does that generally increase the bite of the brakes then?

Tomthumb: I’ll go take a look now. I didn’t preload them, taht wasn’t in the instructions. Thanks for the tip.

Guess I’ll need to dial the pads in again after that.

out – it will move them in, so you need to take the pad out.

bedding the pads in will give the biggest improvment, but having the lever in the correct position when hitting the disc will increase leverage and reduce lever travel.

Cool, I’ve just been out and preloaded the arm/cable and reset the pads with the dial and it’s sorted out the lever travel problem and I have some stopping power now. I’ll bed them in properly on Sundays outing. The preloading has them feeling how I’d hoped though. Just riding down the street they have some bight now and work one fingered.

I (wrongly) thought when fitting them that preloading the arem would just move the pads closer to the disc, but that wasn’t the case.

Thanks for the help guys. Much happier now 😀

PS – I did have to dial the pads out after preloading. I meant dialling them in after the bedding in process though.

Re the noise, you did clean the oil off the new disc after you fitted it?

Re the noise, you did clean the grease off the new disc after you fitted it?

A little brrr buzzing noise if it’s gentle is normal in my experience. Not sure exactly why but I’ve assumed it’s due to the vents on the disc if you have them.

Also I find I get this noise (which is quite satisfying) when using Organic or Kevlar pads.

Sintered pads… squeeeeeeeeal! At least after a few rides and definitely at the slightest hint of water or mud.

Don’t worry too much about noises. You’ll get all kinds and it will bug you, but you learn to live with it. Washing the bike after a muddy ride and it will grind away too. A good rinse down on the brakes after cleaning with water that’s got as little crud in it as possible and spin the wheel, gentle apply brakes, and repeat. Usually clears it. But then next ride it will soon go away too.

Never bothered bedding pads never had issues.
As for locking up its something you want to avoid anyway.

I managed to get out today instead of tomorrow, just wanted to say thanks for the advice above. The brake is awesome now! Loads of stopping power even through the muddy stuff.

They are noisy when cold/at the carpark, but that quickly went and only came back after a long, long slog uphill. Again, quietened down after pulling the lever once or twice.

I found I was riding LOADS faster because I wasn’t trying to keep the speed down. I knew I could slow/stop quickly if I had to so it gave me a lot more confidence to go faster. The rear vee hardly got used, and I’m very pleased with this set-up, until I need a new rear wheel then I’ll probably go disc on the back as well.

Never imagined me saying this but…I am a disc brake convert. Never imagined I’d be saying that, but the little bit extra weight is worth it for being able to slow down! Best upgrade I’ve made. I need a fatter rear tyre now though, as the 1.9 on the rear isn’t coping well with going so much faster over the rocky stuff

Cheers, Martin

PS – don’t think there was any oil/grease on the disc. It was dry when I took it out of the packet and fitted it. It will be well burned of now though if there was!