retro-fitting disc brakes

jumbolugs

I've been wondering if it would be possible to retro-fit road disc brakes (e.g. Avid BB7s) to my touring bike. It does not have disc mounts on the frame, but I have noticed Avid make mounting brackets such as these:
http://www.wiggle.co.uk/ProductDetail.a ... %20Bracket
...is that what these brackets are for, or are they intended for mounting Avid brake calipers to ISO disc tabs?

I know almost nothing about disc brakes as you have probably guessed by now.

maddog 2

there for fitting post-mount calipers (Avid, Formula etc.) to ISO disc tabs, as you suggest.

you'd be better off getting some disc tabs welded to your frame, or better some new ISO dropouts, by a reputable frame builder, rather than try and bodge something,

simbil1

You could always buy some disc ready forks and then just have disc brakes on the front where it matters and your old brakes on the back.
You don't really need a disc brake on the back IMHO.

grahamharpin

I did this with my touring bike by changing the fork to a disc compatable one. Most of the braking is done by the front wheel anyway so you can leave the back as is. There are a number of forks out there for cyclocross bikes with discs or perhaps Edinburgh Coop can supply a fork from thier disc touring bike.

In my case the disc is much better than the cantilevers (brake grab and squeal all gone) but I also have a Dawes Galaxy with steel forks and cantilevers and the brake performance of the disc bike is very similar to the Dawes.

spivvy

http://www.wiggle.co.uk/ProductDetail.a ... 0Retrofits

robbarker

You need forks designed to take disc brakes. They generate significant forces and using forks not designed for them is potentially dangerous. At the very least consult a good framebuilder like Dave Yates.

Sea_Green_Incorruptible

On a related note... are there likely to be any problems wiring up a retro fitted disc to a Shimano STI shifter? I quite fancy having a go at this conversion on one of my road bikes - the loss of braking in the wet on cantis still scares me on my commute sometimes...

Monty Dog

Don't assume welding or brazing tabs to a non-disc frame is a good solution - the frame tubes weren't intended to take stresses at these point and could result in a nasty frame failure - I knew someone who had tabs welded to his Ritchey MTB frame - took it to Moab untested and had a spectacular crash on the first outing as the seatstay sheared. Likewise, a road fork wasn't designed for the stresses from a disc brake, and there are plenty of road disc forks now available too. For laden and off-road riding in all conditions a disc brake gives an unprecedented amount of power and control that cantilevers can't deliver - a worthwhile investment if you feel the need for better control.