View Full Version : Disc Brake opinions


onrhodes
01-04-2005, 07:42 AM
I'm using my bike mostly for commuting and some off road riding here and there. I am just totally into the concept of throwing disc brakes on my Redline. Mostly because I think it will be a ton of fun.
However, being a redline I only have 1 choice of wheels right now. The Sagitta disc wheels because they are the only 130mm spaced rear disc compatible hub. The cannondale are also, but after checking with my local C-dale dealer, I found out that they won't sell their wheels after market. So that leaves me with the Velomax.
What are your experiences with disc wheels and cross bikes? I'm not worried about UCI rules since I don't race the thing, I just want to know what people have found with their setups?

Dan Cas
01-04-2005, 05:28 PM
in about a week.I had my cross bike setup as a disc brake bike for a short period of time with a steel fork and switched to cantis with a carbon fork.I am now swirching back to a carbon disc fork.I can't ride for a few days due to a minor surgery.

I can tell you that discs are better brakes.No chatter,no squeeling,no problems and honkin brakes in all conditions.

My ti frame is spaced at 132 and I can spread it to 135,no problem.Just a little hard to get the rear wheel in.You may investigate changing the axle on a basic hub like an XT and making your own wheels.I don't know if the hub shell width is too wide or not.I would not spread an aluminum frame 5mm's tho.

The lovely wife has ridden the Poprad I got from you Once and only once.....

I'll post in about a week.

Dan Cas

cxwrench
01-04-2005, 06:27 PM
the one thing that really limits how well any brake will work (given proper adjustment, good pads/rotors, etc.) is traction. sure, you can put monster disc brakes on a cross bike, but you still have that small, relatively hard tire as your contact patch. sure, it might be fun to do, but it's not really gonna get you anywhere in regards to braking ability.
on the other hand, your rims will last longer because they are no longer friction material. and minor wheel abuse won't hurt your braking performance.
it's kind of like the kids w/ the honda civics w/ bir brake kits and 18" rims mounted w/ normal street compound tires. all they get is flat spots...

damon
01-04-2005, 09:23 PM
You may investigate changing the axle on a basic hub like an XT and making your own wheels.I don't know if the hub shell width is too wide or not.I would not spread an aluminum frame 5mm's tho.

Problem with this theory, as far as i can think, is that the critical geometry for a disk hub is the distance between the outer/locknut face and the disk rotor mounting surface. Since the drive side is relatively fixed in space, that means the non-drive/disk side is kind of stuck, too. The only workaround i can see is to:

a) not worry about a rear disk
b) switch to a 7sp freehub body, effectively taking that 5mm of space off the drive side and getting the disk to line up that way. If you ran a 9sp cassette, you can apparently fit 8 of those on a 7sp body, if you are inclined to worry about how many rear cogs you have. On a commuter, i can't imagine it would matter much (never has to me).

Point b is mostly theory on my end, though, so take that advice for what it is worth (that is to say, free...).

Good luck,
-Damon
(putting a disk on the front of his bianchi, soon!)

theraindog
01-04-2005, 10:42 PM
If you ride in nasty weather, discs are the only way to go for cross riding or commuting. The additional stopping power is nice, as is ease of adjustment, but the real kicker for me is the consistent performance across all conditions. Whether it be the start of a ride in gorgeous dry weather or the end of a rainy, sloppy, muddy ride... brake performance is incredibly consistent. That comes in especially handy in traffic.

My only wish was that my Avid BB7s had the modulation of the Hayes hydros on my mountain bike. Such are the limitations of cable discs, but I'll take them over cantis or v-brakes any day.

Coolhand
01-05-2005, 06:03 AM
I have those Velomax wheels on my 05 Redline, and they are darned nice.

czardonic
01-05-2005, 11:44 AM
I wonder if you could shim the caliper outboard so that it lines up with the new disc position. . .

Gripped
01-05-2005, 12:12 PM
If you ride in nasty weather, discs are the only way to go for cross riding or commuting. The additional stopping power is nice, as is ease of adjustment, but the real kicker for me is the consistent performance across all conditions. Whether it be the start of a ride in gorgeous dry weather or the end of a rainy, sloppy, muddy ride... brake performance is incredibly consistent. That comes in especially handy in traffic.


I ride and race in the Pac NW. I commute and ride year round. I get lots of mud in races. I get lots of rain in the winter. I have a set of Avid Tri Aligns on my commuter/pit bike and I have a set of Avid Tri Aligns on my racing bike. I wouldn't trade them for discs because the stopping power is great in all conditions (with Kool Stop Salmons). Set up isn't bad and maintenance is a breeze. And I even have an '04 Redline with disc tabs.

Tommy3172
04-04-2005, 06:45 PM
I'm using my bike mostly for commuting and some off road riding here and there. I am just totally into the concept of throwing disc brakes on my Redline. Mostly because I think it will be a ton of fun.
However, being a redline I only have 1 choice of wheels right now. The Sagitta disc wheels because they are the only 130mm spaced rear disc compatible hub. The cannondale are also, but after checking with my local C-dale dealer, I found out that they won't sell their wheels after market. So that leaves me with the Velomax.
What are your experiences with disc wheels and cross bikes? I'm not worried about UCI rules since I don't race the thing, I just want to know what people have found with their setups?

I have a 2004 C'dale cyclocross disc and was in a somewhat similar position in that I was interested in getting another wheelset and I needed to know the rear dropout spacing. Upon e-mailing cannondale, they told me it was 135mm. Basically, cannondale isn't your answer either way. With regard to the setup . . . I love having discs, they look unbelievably cool and they perform like a dream. I have avid mechs ( I use road tires most of the time which imho makes the discs look even cooler)

jroden
04-05-2005, 06:14 PM
I used Avid discs on my giant last season and they work really well, especially in wet, muddy weather. I don't think they are the future of racing, in large part due to the extra pound they add to the bike, but they are a far superior brake to any sort of rim brake I have ever used. I'd use them on a road bike if I had the option.

OnTheRivet
04-05-2005, 10:23 PM
If you don't mind spending some cabbage you can purchase a set of Hugi 240s MTB disc hubs and convert the rear to 130mm by ordering a road end cap. I did this with a set of regular 240 hubs I got. The only difference between the road and MTB hubs is the cassette side end cap that pops off is 5mm longer on the MTB hubs. You can get the part number off the DT website tech manual PDF, it shows an exploded isometric of all the hubs with applicable P/N's. One caveat, I did this with non-disc hubs but they appear to be the same.

mgp
04-07-2005, 02:51 PM
The Hugis won't work, nor will any other hub out there. I emailed every freakin' hub manufacturer (DT-Swiss, Phil, White, Pauls, etc...) a while ago asking this question, since it seemed like you could just swap in a different axle. Nope. I even emailed Lennard Zinn and we went back and forth a few times on this and came to the same conclusion, it won't work (see below for his suggestion, though...) The above posts nailed, there just isn't room back there for the disc mount and cassette. The Velomax hub works because the hub shell is narrower, as it is specifically designed for 130mm spacing. If you want to use a 130mm spaced hub, the Velomax is your only option.

Back to what Zinn recommended for my *aluminum* frame Redline. Stuff the 135mm spaced hub in there. Yes, in an aluminum frame. Oh Lord, the humanity! No! Your bike will explode into many small pieces and kill small children while the earth quakes in fury!

I asked him about how this flies in the face of cycling frame dogma and he pretty much laughed about it. You are spreading the frame 2.5 mm on each side. It is a non-issue. Just for kicks, look at how much your frame sways when you are really beating on it out of the saddle, etc... At least that much. ;)

I've been running it this way for about 7 or 8 months without issue (about 12 hours a week of commuting and singletrack use). Yes, getting the rear wheel in is slightly more difficult, but it isn't that bad.

Oh, and do I like the Avid discs? Yes. I would *not* race them--the setup ends up being too heavy. For a commuter, however, I would never go back. Your braking is the same as well set up cantis in the dry, and in the wet it is almost the same. It is also very nice when you grab a handful of brake in the rain and not only do you have good braking, but you don't get the dreaded rim grind (I used to go through a rear rim every 6 months--lots of sand on the roads and trails in D.C.).