Brake caliper reach "margin"
 

Brake caliper reach margin

Hello everyone,I've recently replaced the front brake caliper on a bike with a vintage road frame and 700c wheels. The old caliper had a 46mm-58mm reach while the new one is 39mm-51mm. The pads on on the new caliper make perfect contact with the rim's brake surface if I put them all the way down (at 51mm), so everything works fine, but I don't have any extra "room" to move them further down and I don't know if this could become a problem in the future (e.g. when the pads wear?).

Can I just keep using this caliper or should I try to return it and purchase something with more reach (so that I have some extra margin)?

If in the future I'll ever need to replace my front wheel, I'll pick either a 700c or a 27" one, so the caliper should keep working just fine.. Is there something else I should consider?

Sorry if the question sounds stupid, but this is a beater bike and I've already spent too much money on it, so I'd like to make the right choice to avoid wasting even more money in the future

EDIT:
I've added pictures in an album of my profile named "Caliper reach"

If the pads align well with the brake track you are fine. Your new caliper is a "short reach" and the old one was "long reach". Long reach brakes are increasing hard to find so be glad the new one is able to align. There should be no future problems but you can obtain a little extra clearance by filing the bottom of the adjustment slot a mm or so.

The shoes on my rear caliper on my bike are at the bottom. I don't foresee this as being any kind of problem.

One can always slightly grind the pads' upper edges to a bevel to further avoid the tire. Andy

Thank you everyone, unfortunately I cannot post pictures yet..
If there's not anything that I should worry about in the future I think I'll just keep it

If you pick the 27" wheel & tire in the future, then make sure you have room. That's going use up at least 8 more millimeters (≈5/16") clearance to whatever the closest point of interference is. Might be even less room if your current tire size is under 32 mm width

Not sure what I think about a 700C on the rear and a 27" on the front. I'd want same size wheels.

PS. You can put pics in the Gallery here on BF and just let us know they are there.

Thanks, I've added the pictures in an album on my profile

Voilà, your pics....

https://cimg3.ibsrv.net/gimg/bikefor...4758f0f060.jpghttps://cimg2.ibsrv.net/gimg/bikefor...8f77eef815.jpg

Without even a mm of extra space below?
I don't really know why but it somehow makes me uncomfortable..

I've got dual-pivot brakes that look like yours, except mine are on the rear. Each shoe hits the rim squarely where it should. Even if my brake arms were longer, I would have set the shoes up exactly where they are now.

If it bothers you take a round file and make the slot a little longer. Plenty of meat down there.

Or invest $$ in drop pads.
​​​​​​https://www.amazon.com/Aican-Aluminu...0788QX964?th=1

​​​​​​https://bdopcycling.com/product/bdop...rs-pair-black/

I did that once, it solved a similar problem. Good suggestion, DH.

If this was a saddle all the way forward or rearward on it's rails I might be uncomfortable too. But for the brake pads I have no issue with going all the way to the end of the slot. The pads don't move in the slot once you tighten the nut.

No, the increase in radius, and the decrease in clearance, will be 4mm or about 5/32".

Given the OP is working on an older road frame that originally had long reach brakes, I expect the fork and rear stay tire clearances are pretty generous.

I'm including the difference of the tires normally on a 27" bike which are usually 32 mm wide. The width of a tire is generally about the distance it adds to the radius of the wheel. And compared to a 28 mm tire many are now using on a 700 C road bike wheel that works out to this.....

((630-622) / 2 ) + (32 - 28) = 8 mm.

Or am I still thinking wrong somewhere? Though I do agree that many road bikes I've had from back in that day were formerly 27" wheels and even then very generous with space. But it's not something I'd assume willy nilly for all when all I have to do is look.