Can a bike designed for cantis or centerpulls be converted to disc brakes (i.e., with the proper tabs welded on)?

Of course it could, but you can probably get a frame that is already designed and built for disc brakes for $100 or less from Nashbar.

All it takes is money. But, by the time that you get the caliper mounts fabricated, welded and repaint your bike frame, buy a new disc wheelset and buy the brakes themselves, you're going to be real close to the price of a whole new disc brake equipped bike.

Thank you. I started thinking about that about ten minutes ago. Don't know much about disk brakes myself, but they can't cost more than a new wheel set every two years. Yep, I figured that one eleven minutes ago. My plan is to convert just the front brake if it's possible, by just getting a new fork with disk brake mountings and the brake. Maybe that will be cheaper than having a custom welding. So, I'm off to the archives.

On the rear wheel, it means brazing new tabs. Probably not overly expensive, especially if you have connections. It's the repainting that costs a lot, so think about it only if your bike is due for repainting. In the front, you need a new beefier fork. Will you be able to match the colour? That being said, there are drawbacks to such a conversion:

– The typical rear brake (installed on top of the chainstay) limits severely your selection of rear racks. So a proper rack costs more.

– In the front, a disc-brake-compatible fork will be beefier, therefore will have less shock-absorbing capacities.

Blue Order quick, edit your post to include the words "patent pending". After browsing through countless online catalogs I've determined that you're the first to think of this. Also, I've determined if I look at one more BMX fork I'm going to puke.

Any LBS will be able to give you a price on the adaptors for these conversions. Can't remember off the top of my head what brands, but they do exist, and are available front or rear, and are specific to 29" and 26" frames. Unsure if anything would be available for cross bikes though.

???

Shock absorbing capacities are a function of fork valving, spring rates (and/or air pressure) and oil viscosity not fork "beefiness".

It is possible to set up many forks to deliver a desirable ride quality regardless of tube diameter or braking type.

^^^ Umm, the others are not talking about suspension forks. Just plain old rigid forks. I'm not sure anyone would notice a harsher ride from a disc compatible fork, but it's not unimaginable.

I'm aware that the original poster was talking about a rigid fork, but all rigid forks aren't created equal.

For instance, the first bike is an old Peugeot and the second one is a Norco Monterey with disc brakes. The fork of the first one is slimmer and has a gracious curve near the bottom, so it will follow much better the irregularities of the road than the fork of the second bike.

There are two effects of that:

1. On a bumpy road covered with snow (mud or sand), front wheel adherence will be better, resulting in better control of the bike (I tested that one personally)

2. Riding the bumpy road or a gravel road with a flexible fork will be more comfortable on the hands.