Originally Posted by
gugie
So, the moral of the story is check both height and width prior to converting!
Before doing a 650b conversion, I would highly recommend that you try putting on some wheels with your intended tire first to see what issues you may come up with. 27" to 700c is a smaller jump, but the recommendation would be the same.
This is the best advice in this thread. I did this and found the brake shoes almost made it. Grinding, filing, sanding the brake caliper arms enough to drop the shoes that last 0.25mm was a lot of work.
Check BOTH wheels. The dropout to brake bridge/fork crown distance can very widely. Some 1970's bikes used completely different size Weinmanns on the front and back. It's not uncommon to find the pads in different locations in the caliper slots between front and back.