Need help fitting caliper brakes around front rack
 

The rack gets in the way!http://bikeforums.net/attachment.php...hmentid=452853http://bikeforums.net/attachment.php...hmentid=452854http://bikeforums.net/attachment.php...hmentid=452855http://bikeforums.net/attachment.php...hmentid=452856 With a side-pull, the upper arm hits on the downward swing. With the center-pull, you have to compress the brakes before placing the rack into position (then put the pads on), which is the best answer I've developed. Its my uneducated theory that side-pulls must have mechanical advantage, but I'm not sure why or how.

1. What caused the transition from center-pull brakes to side-pull?
2. Are there any side-pull brakes that will work for this application?
3. Can anyone tell me of a brake that will actually reach the rim? (looks to be about 70mm reach)

Mount the brake properly, then worry about the rack.

The brakes I have, unfortunately, do not make contact with the rims as they are too short. Hence, I am asking for recommendations/suggestions as to which brake to use.
Thus far, I have found this op-piece advocating for the use of center pull brakes, specifically, the Paul 'racers', which are outside my budget for this build.

You are going to have to extend the threading on that fork, too. I recommend seeing what other racks the LBS has when you bring the fork in.

That's what I think too. Since you're obviously planning to carry a load on this bike, you're going to want reliable brakes.

The first thing that I would do would be to measure the vertical distance from the brake mounting hole to the rim's brake surface. That'll give you the brake reach measurement that you'll need to select your brakes. Tektro has a dual pivot model (R556) that has 73mm of reach and might work for you. It'll handle fenders and a pretty wide tire too.

Once you have the brakes figured out you can attack the rack. You might have to bend the mounting arms or use spacers to move the arm mounting points outward. I've found that rollers from spare chain links sometimes make perfect spacers.

@wilfred: 10-4 (or should I say 1"- 24 tpi) on die-cutting more threads. It's on the to-do list :)

@retro: Here is a shot of what the r559(taken from a tandem I had converted from 27s to 700s) looks like, but the arm still makes contact with the rack. http://bikeforums.net/attachment.php...hmentid=452883

Thanks for all the advice thus far!

I suppose I have had and continue to have a couple options:

1. modify the rack to accommodate the swing of the caliper arm
2. figure out which brakes were installed on this particular set-up initially and purchase those/ find a suitable replacement
3. succumb to the universe's way of saying "try again"; scrap the fork/rack I have and get a new fork/rack set-up

I'm leaning towards the second option right now, because I think it will be a fun challenge to find the right part to suit this rig. Also, I always say the more I save from the scrap heap, the better.

The fork was likely originally for 27" wheels, so knowing what brakes came on it originally will not be much help with your 700C wheels. You need to be concerned with getting a working set of brakes before you worry about rack interference.

Would you build a car based on a trunk lid you found?

Edit:

On second thought, you seem to be trying to fit the rack stay between the upper and lower arms of the caliper with the brake wide open. Would the rack fit above the caliper if the caliper is connected to a cable and pulled closer to the tire?

@Wilfred Laurier: Good idea about the caliper arm on the underside of the rack arm, but the rack will not bolt on with the caliper arm beneath. http://bikeforums.net/attachment.php...hmentid=452893

The rims on there now are 27s. The fork is a miyata 1024 fork so I imagine it was designed for 27s, but maybe 28 x 1 1/2s?

So put a slightly sharper bend in the stay.

That's almost certainly the best option I have given the parts on hand. Thank you. However, I would like to retain the current height of the rack as there is an eyelet on the underside of the front of the rack, which I can only rationalize (given the distance between it and the tire) can mount to a fender. I would like to keep everything as is and find out which center-pull caliper brakes are meant for this rack and fork combo. A trip to my LBS is in my immediate future. And if I come up empty-handed, then I will positively pursue modification of the rack stays.

There is no headset on that fork. The brake will sit lower relative to the rack once you install a headset

**********

No.

You are right,sorry, wasn't thinking straight

'sallright.

Is there something funny about this rack? do you need to drill holes into the top of the fork to install it?

@cyclist2000: There are already threaded holes in the sides of the crown. The rack fits perfectly as that is how it came, but the brakes weren't included when I found it.

the front racks that I have seen, normally have are connected by the brake hole, I have never seen one that is drilled into the sides of the fork. I think that is why you are having the problems with the brakes.

It looks like it may rear rack that has been rigged up to work on the front.

They're rare,but I'm pretty sure it's a front rack. Like this:
http://bikeforums.net/attachment.php...hmentid=453726


I'm thinking that the fork may have originally used a narrower center pull caliper.

The rack that is in your photo is connected to the brake hole in the center of the fork crown, not the side of the fork crown as shown in the OP.

And I have never seen a fork that had eyelets on the fork crown. But I haven't seen every bike out there and I always could be wrong, but I don't think this is common.

This might be a better option: http://www.rivbike.com/product-p/r1.htm



The Schwinn Voyager from the early 80's had mounts on the crown.

http://1.bp.blogspot.com/-y1hAtyI7N_...00/Scan+4.jpeg

http://i93.photobucket.com/albums/l4...2/CIMG7587.jpg

Dear Abby,
I've got a bunch of junk parts that I want to assemble into a touring bike. The problem is, they don't fit each other. How can I make them work?

You need a longer reach brake caliper . than what you Have... Go Find It.

weak on independent problem solving , touring may be too challenging, , learn more First.

wow, this took a turn for the worst... The bike shop guy was baffled and suggested a new rack. I wound up bending the rack arm threading it through the arms of the r559 I had. all of the centerpulls I tried to use weren't able to clear the rack arms or didn't have long enough reach. When the brake pads wear enough, there will be interference again, but the r559 will work (it just requires careful monitoring).
Ps. I had been asking if anyone had seen this before, not for you to poop on my ingenuity. The holes that are tapped into the crown look totally stock as do the pieces of metal welded onto the side of the fork. That is to say, the paint that surrounds these features is equally as old as the fork.
I remain interested to see if anyone out there is familiar with these totally STOCK rack mounts from miyata.

Single pivot sidepulls do not have any advantage over centerpulls. Single pivot sidepulls became popular because racers used Campagnolo sidepulls, and people wanted what the racers used. Stopping power is not important to racers, however it is to real world riders such as commuters.

Short reach double pivot sidepulls, however, are very powerfull.

Tektro and IRD make long reach double pivot sidepulls. Diacomp still sells the 750 centerpull, and if you can find a pair, MAFAC Raids have a long reach also. There are some very expensive copies of the Raid as well.

A few years ago Bicycle Quarterly had an issue in which they covered the development of bicycle brakes.