Hey all,
I am needing some help with some measurements. I need to know the "minimum" reach for Mafac Racer,
and Universal #61 center pull brakes. I am wanting to use centerpulls on a project frame with a reach of around 50mm.

Thanks much,
Chris

Here's the answer for the Mafacs:

https://ruedatropical.wordpress.com/2...l-brake-specs/

I have a set of Universal 61's sitting in a drawer that I measured, and the rear brake has a minimum reach right about 50mm, however the front is about 55mm. It looks like I may have filed off some material at the top of the brake block mounting slot on the front brake, so it may originally have been more than 55mm.

Revision 1 - I found this info on the web which suggests just the opposite, namely the front has a shorter reach than the rear. Since the mounting bolts are removable and interchangeable, I may have swapped them for some reason. Anyway, here's the link:

https://www.classiclightweights.co.uk/universal.html

Dang, Dirtdrop, that link had the best info and specs! Wish we could get info like that on all of the old vintage parts.

Thanks to all! Really good information

Cheers,
Chris

Great Link Dirtdrop!

WEINMANN (just had to add these too...)

Weinmann had both a short (#610) and long (#750) caliper. They were commonly used together on a bike as a pair. The shorter were often used for a front brake, with the longer caliper used for the rear - although this could really depend on the bike and even the style of dropouts (I have one bike which is best suited for 610s on both front and rear). The model 610 had a reach of 49-61 mm. ... the 750 was 57-75 mm.

UNIVERSAL

There were two different lengths available for the model 61 brakes, too. Here is a photo showing the two versions together: https://farm3.static.flickr.com/2240/...d33d61da_b.jpg

The LONGER arch style has an adjustment range of roughly 55-70 mm. (that's by my actual measure)... and that is measured from center of mounting bolt to center of brake pads. Notice the shorter caliper in the photo ALSO clearly has a shorter brake pad adjustment slot, so this allowed much less total range of adjustment. This caliper appears have a reach of around 48-58 mm.


MAFAC

As I recall, the "Adjustable" version of the Mafac (mentioned in Dirtdrop's linked comparison tables) used a vertical slot through which the mounting bolt fitted rather than a simple hole. This would raise or lower the entire central "yoke" itself for a best fit on a frame. These are really pretty rare finds.

Both my '74 Peugeot PX10LE and my '73 Gitane Tour de France came with Mafac Competitions with one slotted caliper. I've never seen adjustable Racers.