malpag3

Where did I go wrong?

So the front brake I bought (Tektro R538) does not reach all the way to the other side of the fork hole for mounting. Crap!? The very top of the bolt reaches but no threads are exposed.

What did I do wrong in the ordering process? What should I look for when buying these?

It's an older Araya steel frame road bike. Lame...

malpag3

I think I am realizing I need "center mount" brakes?! Is this true?

jrod

i think you have a bold for a rear brake. find an old front brake and swap the bolts or get a front brake.

bbattle

Snagging a bolt off an old brake is probably the best bet.

If you are using an older frame from the 70's or early 80's, it may have had 27" wheels(630mm). To run 700c wheels(622mm) you may need long reach brakes like the Tektro R556/Rivendell Silvers sidepull brakes or the Dia Compe Mod 750's. Heck, on some old bikes you'll need either of these even if you use 27" wheels.

Loosescrews.com is a good place to find all sorts of hard to find or even hard to describe parts. If you aren't sure about something, give them a call.

malpag3

No, I bought a pair of brakes. One bolt is long, and one is short, indicating front and rear.

The front brake bolt is not long enough. You're saying I can swap the bolts using an older front brake? I do have the old Dia-Compe center-pull brakes I took off this bike.

malpag3

Thanks bbattle. Yes it did have 27" wheels. I did buy "long reach" Tektros for this purpose.

peabodypride

Probably designed for recessed nuts, where on the back of the fork there is a wider opening to accept a nut that sits flush with the fork crown. If your fork is not designed with this recession, get a longer bolt.

malpag3

Yes, no recession for this nut like on my more recent road bike.

davewins

try putting the bolt in first. see if it touches the end of the threads. if it does you will see how much room you have to tighten it down with. the threads on my front break only make it about 3/4 of the way through the fork, the bolt does the rest.

malpag3

yeah, no way the allen nut fits inside the hole in either fork or seat stay.

operator

You need to drill out your fork 5/16 drill bit to accept the recessed nut. Assuming what you've already described is true. The other option is to go for nutted brakes, which are mostly shyte nowadays. Recessed brake nuts come in different lengths, enough to cover pretty much every possibility.

darksiderising

Let's see a picture before you start drilling.

krusty

Yes.
What you have is an older frame, designed for brakes that had long bolts on them. They did reach clear through, and simply had a nut to hold them on. For God's sake, don't use one of these POS brakes. Your new ones will require the hole on the back of the fork to be enlarged for a modern recessed nut. Trivial to do.

Metricoclock

pictures needed

baxtefer

wow. operator actually gives out useful information for once.
who knew it was possible.

malpag3

Yep it sounds like drilling is required! It doesn't sound like too hard of a fix either! nifty. Thanks in advance guys.

Pictures here.

peabodypride

woah the new forum picture upgrade is sick. way too web 2.0 for this site though.

krusty

Just make sure that the reach of your new brake will be compatible with your rims and that older fork before committing.

andrewro

Agree with the above statement - make sure the reach is enough, then I would drill the rear hole so the thru-bolt will pass thru it. Or take it somewhere if you're uncomfortable doing it yourself.

malpag3

Yep, I placed my 700c road wheel from my road bike in the fork and it did fit! So now to drill at the shop.

5/16 drill bit. Any special precautions otherwise? It's a steel frame.

krusty

Watch for the bit pulling itself the last bit of the way and jamming. Use lube on the bit. Go slow at the end. Mount the fork firmly so it won't whip around if the bit grabs as it exits.

stachemaster

Didn't see it mentioned above, but for anyone wanting to run two recessed-nut brakes on a old frame: what mount the new front brake on the rear, making sure to swap the pads around so the pads dont slide out of their cartridges, and fix with a regular nut.
mount the new rear brake on the fork (again, swapping the pags l-r) after drilling out, and use a longer recessed nut (like one for a carbon fork) to hit the bolt. your brakes should've come with several recessed nuts of different lengths.

krusty

Bad idea. Most modern brakes are designed with differential braking action front vs. rear (i.e. stronger front due to a dual pivot design, weaker back, sometimes with a single pivot design). The front brake must go on the front, and the back one on the back if they are like this. Inspect carefully. If there is a difference between the caliper design, put them where they belong. There's nothing preventing you from enlarging the hole on the back side of the brake bridge to take a modern recessed nut, just like the fork.

stachemaster

Fair enough, but that would only be valid for lighter-weight brakes where there is a double vs single pivot, i don't have the stats to agree with the "most" comment. I assumed (i know, i know) most doing this type of chop job in the first place wouldn't be using high performance short reach brakes; that any tinkering like this would be expected to be on a 700c conversion from 27in. My comment stands for those using dual double-pivot brakes.
[fwiw: the r538's from the op are both dual pivot]

krusty

Yep. Perhaps I was a bit harsh with my negativity, and to be honest, my experience is mostly with DA and Record brakes, which are specific front/rear. It's just another thing to be aware of when looking for innovative solutions, which yours was.