The distance from the center of the mounting hole on my fork to the center of my rims is from 69-73, depending on how/where I measure it. The bike shop had ordered the 55-73 for it, after measuring it themselves, but it's been 2 weeks with no brakes, so I went in and got my money back to just buy them myself online.

Anyway, I found 55-73mm, and 70-80mm reach. What the heck one do I get?

I'm fairly certain the bike shop tried something like 57mm, and they hit the tire, though only by (seemingly) a few mm.

I'm leaning towards the 55-73, seeing as that's what they ordered, but I do worry about them being too short, as they're right up to the max size I measured.

I could always get creative if they're too short, ie shave away some of the pad, or grind out the slot that holds them an extra mm or 2, but too long would be pretty unusable.

Thoughts?

70 is a pretty big reach, even for a bike that came with 27" wheels, is now fitted with 700c, and had clearance for big tires and a fender. I'd order the 55-73. Harris have the Tektro 556 in nutted, which you might need, too, depending on your fork.

I think on sheldon's page, it says measure the reach by placing a ruler on the fork with the wheel in place, but you actually need to measure where the brake pads would be, if they're mounted on the brakes, which is around 1in in front of the fork.

Also, if these are calipers, when the pads wear away, they will hit a bit higher than when they were new, so that's another consideration.

If this is a 27" to 700c conversion, the 55-73mm reach should work.

Thanks both of you. I just seem to fail at basic measuring. I had a brilliant idea though. I haven't taken out the trash yet, so I got out the old crappy brakes, and set them up, and then measured from the center bolt to the center of the pad. Turned out to be 67mm, so yeah, looks like the 55-73 will do the job.

If you're just replacing a brake, with no other change, telling us as much about it (like does it have model number?) as you can will probably get a good response about what you need. That's probably true if you're changing wheel sizes, if you say what changes you're making

73 , brake height pad falling in the middle of the adjusting slot like 60-80 is fine ,
get a dual pivot like Tektro brand. type.. at least for the front.

This is true for center pulls and 1/2 of dual pivots but not side pulls. The brake arm travels along a circle with the pivot as its center. The brake pad travels along the tangent of this circle as the brake pad approaches the rim.

Where the pivot is to the right or left of the rim, the brake arm moves in an upward arc. The brake arm will move more as the brake pad wears. This means the brake will move in an upward arc and the worn pad will tend to hit the sidewall, if the pads' vertical position is not changed to compensate for wear.

However, a side pull's pivot point is directly above the rim. The brake arm is approaching the 180 degree point of the arc. The brake pad is moving fairly close to horizontally at the point of contact. It's actually moving very slightly downward. Thus, there is no danger to the pad creeping upward with wear. Also the nearly horizontal arc means there is very little danger of it creeping significantly downward, unlike cantilever or linear brakes.

Therefore, one can adjust the vertical position of the brake pads for side pulls once and forget about it. The brake pads will have no significant change in vertical position with wear. Keeping side pulls centered horizontally is a different matter.