Buddha Knuckle

Anybody out there tour with disc brakes? What are the benefits? What are the problems? I wonder about the durability and simplicity of disc brakes in such an application. I use cantilevers, and I love them , but I'm curious about alternative lifestyles.

Peace,
BK

Michel Gagnon

As far as I am concerned, the major problems are:

1. Need for a beefier fork to whitstand the braking torque. This is not a major factor weightwise.

2. There is (might be) a conflict between the brakes and the rack and/or panniers.
This is a major point and you should make sure you are able to attach your racks to the bike. Also make sure that the panniers won't hit the brake structure, get rubbed, etc.

Finally, there are a few advantages, mainly that your wheels may be wildly out of true and that your braking won't be affected by water or mud. However, current rim brakes with Kool Stop pads offer very good performance when wet. Some people consider their disc brakes easy to maintain, but I wonder what is the price of parts or their availabiity in remote corners.

Regards,

AndrewP

You wont have to worry about overheating your rims on big descents when heavily loaded

FLYBYU

Don't get hydraulic disc brakes if you do, I would go with Avid mechanicals, much easier to maintain.

MichaelW

You dont have to worry about wearing your rims too thin.

Buddha Knuckle

Right on,

Thanks for putting up with me as I continue to flog this long dead horse.

mgagnonlv, I am curious if you have encountered the rack fit problem yourself, or if can elaborate somehow. It seems to me that that is a potentially big issue for a touring bike. Disc brake availability problems can be overcome if you have both canti and disc mounts (a la Karate Monkey), provided you settled on a wise brake spec BEFORE setting off on a tour.

And a question to FLYBYU, what does maintenance of Avid Mechanical Discs demand? Can you replace Avid Mech Disc cables with ordinary brake cable or do they require proprietary cables? Are special brake levers needed? I agree that hydraulics are time bombs on touring bikes.

BK

Michel Gagnon

No I haven't. I have looked at the rear end of a friend's bike (unsuspended MTB), and the location of the brake itself just about cleared some rack struts but not all. When it came to panniers, the left pannier needed a wood block to prevent it from interfering with its mechanism. He settled the issue by using his older bike on tour.

I have also read many reports and clues by a few gurus regarding that issue -- namely on the Touring list. See https://search.bikelist.org


Regards,

trmcgeehan

I recently test rode a Giant touring bike, and I was disappointed how bad the mechanical disc brakes were. The LBS guy said it takes a while for the discs to get seated in. He said the discs should be replaced annually.

Michel Gagnon

The first part is true: discs take a while to get seated in. I'm not sure exactly why, maybe it has to do with the oily skin of people who assemble the parts.

As for replacement, it is the same as for rim brakes: it depends a lot on your riding terrain and style.

FLYBYU

I have Hayes mechanicals on all my bikes, but I understand that the Avid's are alot better, they are the same as any other brakes, you don't need special brake cables at all. As for maintence I hardly ever touch mine, occasionally I adjust the barrel adjusters out to adjust for cable stretch/brake pad wear, but you have to do that with any brakes. On my Hayes I've had the same brake pads on the one bike for 2 years now and they still have alot of life left in them. If you want to really improve the performance of you brakes, take the pads out, burn them off with a propane torch, then sand them lightly and reinstall, then wipe the rotor off with rubbing alcohol, they will work like new again. Also when you test ride a bike with disc brakes it will feel like they are crappy, it takes a while for the initial glaze to wear off the pads, then after that you can easily send yourself over the handlebars. I have a rack and panniers on my mountain bike with disc brakes, I took a long 8mm bolt for the disc brake side and added spacers to it so that the rack clears the brake mechanism. As for hydraulic brakes, they are a pain, I find that they get air in the lines and then they drag on the rotor, they need bleeding which is a pain, and I've had seals go in the caliper's, then you get DOT 3 brake fluid coating the whole brake and your fork, which is really hard on your paint and pretty much destroys your brake caliper, then in my case it took 1 month to get my new brake caliper back from Hayes on warrenty, never again.

prestonjb

Remember, while the disk will save your rim or prevent a blowout, the disk does not offer a large increase in braking performance (downhill). Disks tend to fail at 1100W (rotor warping, hydraulics melting off). Most disks can handle around 900W continuous whereas a good set of rim brakes can handle 700-800W continuous.

Buddha Knuckle

Say what?

I don't know if I've ever generated 1100W on a bike, but now I have a target to shoot for.

(just kidding, prestonjb)
BK

prestonjb

Didnt think of it that way...
want to see what happens when a tandem hits 2000W on a carbon wheel and drum brake!!! look at this mess!

https://geocities.com/cyclebikers/July_23_Wed/

ya got to scroll down a bit to see the pic..

Buddha Knuckle

Okay Prestonjb,

I see what you mean.

Respect.

I'm curious, did you make any changes to your tandem after that episode?

BK

capsicum

Dug up from the dreggs of the archives.

I don't get why cars have been using hydralic disk brakes and hydraulic everything on earthmovers for about 40 years, and motorcycles for 30 years without problem with low and easy maintainence in fact no one would choose mechanical moto breaks for any reason other than cost of manufacture. Yet bicycles have that many problems. The basics of hydralics don't change and the size of motorcycle components is not much different from that of bicycles with the exception of the disk thickness and diameter.

Other than that, good thread it answered much.

jhershbine

I just got back from a 7 day tour from Birmingham, AL to Chicago, IL on my Giant OCR Touring and can say the Avid mechanicals did a superb job. Kentucky had some unbelievable grades I came down, and everytime I reached for them there was plenty of "Whoa" power. I also had 3 days of rain, and in the wet they are head and shoulders over rim brakes. I am a believer in discs, but did have to modify my racks some to get everything to fit properly.

skookum

Personally,
I can't see any reason to switch to disc brakes frpm cantilevers, but my bike is set up the way I like it.
As a cyclo-tourist I'm conservative, I am going to use what works until something new has been tried and tested and is demonstrably better. I see a lot of bike shops pushing disc brakes and telling people they have to have them because they are the newest and the greatest. I realize its tough running a bike shop but this kind of thing just discourages people from cycling.

However, just so you know I'm not an old curmudgeon, I am willing to be convinced.

I expect as the technology is refined they will probably become the brake of choice. But not yet.

Juha

I would imagine there is no reason to use discs in both wheels of a touring bike. If you want better rain performance etc, would it not be sufficient just to change your front brake? After all, that is the brake you use for stopping, right? At least you would not have to worry about rear pannier & rack setup.

--J

halfbiked

I concur. Also, are there issues with grafting a disc brake to an old frame? On the front, you just buy new forks. Does the rear frame need to be changed?

daveridesbikes

you can buy racks made for discs (they are regular racks that come with longer bolts and spacers) , and disc brakes on bikes are over 10 years old and proven. i have discs all my bikes that i have bought in the last 5 years (that is 5 bikes by the way) i am a bike messenger and i tour regularly, i have never had any problems with discs that is not comparable to rim brakes, i just have them less often, and the ease of pad change and adjustment (both are tool free) makes it my brake of choice as someone who rides about 200 miles a week just at work, and i have to do it in the rain, snow, ice, etc. always fully loaded.

matchy99

Mechanical disc brakes like the Avid bb7 are very reliable, powerful and easy to maintain. They use standard V-brake levers so reliability is as good as rim brakes. For an extended tour in third world countries all you would need to bring are extra brake pads and extra brake cables and perhaps an extra rotor if you are very unlucky. In most cases you will only have to replace the brake pads after thousands of miles and occasionally adjust the brake slack using the barrel adjusters and/or caliper knobs. As mentioned, your wheels will last much longer without the rim brake wear. Disc technology has been refined and perfected over the last decade making mechanical disc brakes great for any touring bike.

Hydraulic disc brakes like the Magura Marta are also very reliable and pretty much maintenance free since the system is sealed from the elements. The only problem with hydraulic disc brakes are if you accidentally shear the brake cable holding the brake fluid or damage the master cylinder on the brake lever. Repair would require many parts you're unlikely going to want to carry on any extended tour so sticking with mechanicals is safer even if hydraulics offer better feel, power, and weight benefits.

wasabi

I guess here in Europe we take the whole disc brake stuff in a less "religious" approach. Fact is that hydraulic disc brakes do a better job than rim brakes, especially in wet conditions. With a loaded touring bike I want the best stopping power available, and as long as I stay in a "highly civilized" part of the world, spare parts are not an issue. However my bike can be equiped with rim brakes just if one day I won't be able to find disc brake parts in the middle of nowhere - high-tech being low-tech compatible

Nigeyy

Where to start?

Well, I tour with a bike with disc brakes (Avid road BB7s), with a frame and fork that has specific disc brake mounts (Dawes Sardar, old steel style).

Advantages: better braking modulation, better performance in the wet, no rim warping issues
Disadvantages: usually need disc specific racks, more expensive (need disc hubs as well as the brakes!), relatively more complex, less likely to find parts in far flung places

What it all comes down to is a personal choice: I love mine. However, unless you have enough money and just really want them, I'd recommend sticking with traditional brakes -the difference between performance of good quality discs versus good quality traditional brakes is just not worth the price cost IMHO. Touring has been done with traditional brakes for many years quite adequately. Whether or not you are prepared to pay for that improvement (that you could argue might not be needed anyway!) and its associated disadvantages is another matter. However, since I've paid already, I'll never be taking them off and I do find them to be an improvement.

FWIW, I do find some "anti-disc" arguments to be questionable, namely the old chestnut that they are more complex and less reliable. I've never had a disc fail for touring nor mtbing (arguably a different but certainly tough environment) and I still use "complex" derailleur gears. The argument that you may not be able to fix a broken disc brake also doesn't wash with me -to me the same argument can be made of traditional brakes (if the arm brakes, what are you going to do? That's certainly not fixable!). There might be some merit to the fact you may not want to use disc brakes for touring outer Mongolia, but even then, carrying a spare calipre with pads and disc may well be more than adequate and even overkill. I say "might" because I'm not touring far out places, so again discs are more than suitable for me.

seeker333

Touring forum must be pretty slow when you have to look for five-year-old threads to embellish.

bgcycles 

I just finished another disk brake touring bike for Interbike.
I will have pictures up on my New Blog in about a week at - brucegordoncycles.blogspot.com

It has Drop Bars and Cable Avids.

There are advantages and disadvantages - a bicycle is a whole series of compromises - one has to decide what is right for themselves.
That is why I build bikes with cantilevers or Disks - with threaded or threadless headsets.
Regards,
Bruce Gordon
www.bgcycles.com