Disc's on a Road Bike

Author
Discussion

mk1fan

Original Poster:

10,648 posts

232 months

Monday 20th August 2007
quotequote all
I have a Scott Roadster S3 that is kitted out with mud guards and rack. It is used solely for commuting to work and back (30-odd miles). It is running 700cx32 tyres and has had drops fitted inlieu of the factory flat bars.

My question is this. Has / Does anyone use the Avid BB7 Road disc set up on a road / commuting / touring bike? And how do people rate the set up?

The current Scott branded rim brakes don't inspire confidence [in me] through the London traffic.

My conversion spec is as follows:
M756 XT 36-hole hub laced to the existing A319 rim.
Avid BB7 Road front brake.
Kona single butted 700c Project II fork.
Avid Flak Jacket cables.

I shall keep the Scott rear rim brake.

Discuss.......


snotrag

14,925 posts

218 months

Monday 20th August 2007
quotequote all
I've seen it on a few roadies, specilized do one, and also CX style bikes.

The BB7 is a really good brake, and would work well with that fork.

The only problem you'll have, is that the limiting factor then becomes the tire, not the brake. You'll have to be very careful in the wet as it'll lock up prettty easy. But, I say go for it!

I think a flat barred, 700c, disc braked equipped 'roadster' style bike is next on my list, perfect for commuting to uni.

clonmult

10,529 posts

216 months

Tuesday 21st August 2007
quotequote all
snotrag said:
The only problem you'll have, is that the limiting factor then becomes the tire, not the brake. You'll have to be very careful in the wet as it'll lock up prettty easy. But, I say go for it!

I think a flat barred, 700c, disc braked equipped 'roadster' style bike is next on my list, perfect for commuting to uni.
I'm running a Trek FX7.3 Disc, and its definitely a case of (on the slippery london roads) the brakes possibly being beyond the capabilities of the slick tyres.

But as its still "the summertime", I'm not going to swap tyres yet. And I haven't got a clue what tyres to go for when the seriously sucky weather hits - its running the Bontrager Race Lite tyres, which are fantastic on smooth/dry roads. But I rarely encounter such things nowadays (the roads are in an absolute mess)

mk1fan

Original Poster:

10,648 posts

232 months

Tuesday 21st August 2007
quotequote all
Cheers,

I did know about the tyre issue. The bike originally had 23's fitted but these (and the lightweight wheelset) didn't cope too well with 15 stone of rider and a stone of clothes / work stuff. I am currently running Victorria 32's which, at £11.99, are a bargain. 32's are the largest the frame will run.

If the BB7 is as modular (if that's the right application of the word) as the Juicy 7's on my S-W's and Stiffee than I won't have any issues with locking up the front wheel. I'd rather that than the will I, can I stop feel at the moment!

It's going to cost about £150 to do the conversion. I may see if any of the LBS's in my area have a disc ready 700c wheel built up (deore and mavic 319 ideally) to save faffing around with swapping the rim over.

I'm off to Morzine next week. If I don't break anything too important / major (like my frame) then I'll bung an order into Wiggle for the gear.

snotrag

14,925 posts

218 months

Tuesday 21st August 2007
quotequote all
I've jsut realised, you said you were running drops.

You better check the cable pull on your brake levers.

Cable discs are extremely dependent on the lever pull, get it wrong and it just wont work.

You better check that first, otherwise you'll have to go back to your flat bars and use V-brake levers.

mk1fan

Original Poster:

10,648 posts

232 months

Tuesday 21st August 2007
quotequote all
The BB7 is available in a Road version designed to be used with short pull of Road levers. The bike doesn't have V brakes but road brakes.

clonmult

10,529 posts

216 months

Tuesday 21st August 2007
quotequote all
And another thing to bear in mind with cable discs (apparently not with hydraulic?) is if you're going to put on mudguards, regular versions with stays that attach around the hub will be an absolute nightmare to fit.

The line between the mounting point by the hub and the point on the guard goes straight through the brake calipers. Huge amount of bending and swearing were involved in fitting the blighters.

But on the bright side, I no longer get a wet back side when cycling through the water in this wonderful british summer.

Paul Drawmer

4,960 posts

274 months

Wednesday 22nd August 2007
quotequote all
mk1fan said:
The BB7 is available in a Road version designed to be used with short pull of Road levers. The bike doesn't have V brakes but road brakes.
V brakes are perfectly adequate for the use you describe - and are waaay better than cantilever or old fashioned 'centre pull' types.

Disc brakes are heavier, more complex and more expensive. Good at working in muddy conditions when the rim is constantly smeared. Do you get a lot of that on your commute?

klootzak

660 posts

223 months

Wednesday 22nd August 2007
quotequote all

Before you go lashing out on Avid discs, try some decent pads in your existing brakes.

My Dura-Ace equipped road bike stops every bit as quickly as my disc-braked mountain bike ... on the road, at least. And that's running 23c tyres (versus 2.10" on the mtb).

It's the Dura-Ace pads that make most of the difference, not the brakes themselves, and at c. £10 a set they have to be worth a try.

k

mk1fan

Original Poster:

10,648 posts

232 months

Wednesday 22nd August 2007
quotequote all
The bike has road brakes, not V's or Cantis, that are running decent Avid pads. When I have riden the bike without all the commuting kit they are very good but once all my work kit is strapped on then they don't work very well.

laurence8165

2 posts

234 months

Tuesday 28th August 2007
quotequote all
FWIW I run Avid BB5s on my XC bike, operated by SunTour Ergotec combined brake/gear levers that were made before even V brakes were invented(!), so they don't really pull enough cable but I just made sure that I placed the cablers a bit further along the operating cam on the caliper. THey work very well with superb modulation. Go for it!