I just changed out the tires on my long haul trucker, I want to try knobbies on it just to see how it rides. I put 2.1" mountain tires on Alex Adventurer 24.5 mm rims. The rear cantilever brakes are going to need a little more slack in order for the straddle cable to go back on. They were adjusted before right on the edge of dragging, but didn't drag. The rear wheel sure seems to be perfectly true so I went ahead and adjusted them for nearly zero slack when I had slicks on.
Now they're going to need just a tiny amount of slack in order to hook the straddle cable back on. I'm guess that the sidewall of the rim is bowed out slightly from the wider tire. Is that something I should worry about, or could it be something else I'm missing. I'm not even a shade tree bike mechanic so I wouldn't be surprised if I'm missing something.
I let the dogs out
The rim sidewall is probably not bowed out at all because larger tires need less pressure because they have less surface area. The issue you're probably encountering is that the head of the cable is not seating in the brake arm because there isn't enough slack. Give it some slack, seat the head of the cable and then tighten it back up.
Originally Posted by Andrew R Stewart
I didn't think about that, you're right. These tires are higher volume/lower pressure than the old ones. I did just what you said and it's fine. Thanks!
Originally Posted by AlphaDogg