fix front brake

[steverod]

Hi again. I've got a front brake. It seems it only fixes to the front of the front forks is that right? The allen key nut goes through the forks and is inside the forks? I would have thought it would be stronger if the fixing screw was longer so the back hole could be smaller? Here's a pic from youtube of the type of hole and a pic of my brake whose screw seems too short. Thanks folks.

[mattsccm]

Bog standard allen key/recessed fitting. Neater than the older type with a bolt through the fork and a nut at the back. Been the norm for decades.

[steverod]

Thanks. It just doesn't seem as sturdy and surely the big hole in the back weakens the fork?

[rareposter]

Thanks. It just doesn't seem as sturdy and surely the big hole in the back weakens the fork?

It's been a standard fitting for decades. Much neater and stronger than a nut clamping onto the back of the fork.

[steverod]

Does anyone drill a 5.5mm back hole? Just enough to get an allen wrench in? Sliding the nut in from below? Attached a pic of the fork.

[steverod]

Here:

[Mike Sales]

As I remember, from working on many bikes, the rear and the front brake designed for allen key fitting have centre bolts of different lengths. The hole in the rear of the fork crown (or the front of the rear brake bridge) is larger, large enough for the sleeve of the allen nut, but not enough to accept the flange at its head. The allen nuts' sleeves also need to be different lenghts. I hope I am clear.
Looking at one of my bikes I see that the rear brake bridge (carbon) is fat enough to need the same components as the front, unlike a lesser diameter steel frame bridge.
I have sometimes drilled out the hole in order to accomodate a more modern brake set.

[steverod]

That would fix the brake to the front and back of the forks which I'm thinking would be stronger. My brake is designed to only attach to the front. Where should I drill middle? Higher? Lower? Thanks again.

[Jupestar]

Are you certain that is not a rear brake? Hence why it doesn't reach?

[Mike Sales]

That would fix the brake to the front and back of the forks which I'm thinking would be stronger. My brake is designed to only attach to the front. Where should I drill middle? Higher? Lower? Thanks again.

Yes, it is stronber, and easier to fit. The centre bolt of your brakes may well be designed shorter because it is meant to fit the longer sleeve of the allen nut, and not to protrude through the rear fork crown hole.
Do you have the allen nut designed for this? If so, the crown needs drlling out to the sleeve diameter, but not enough to accept the head flange. I would expect the crown to have a narrower hole, designed to fit the brake centre bolt, which needs to be enlarged. If so, it will be in the correct alignment.

Edit to reply to Jupestar, who may be right. If the brakes came as a pair though, the rear might well be shorter again to fit to a narrower rear bridge.

[rareposter]

https://youtu.be/q4ay12CSF48

Does this video help?

It's not clear from the pic if you're trying to drill a hole in the fork to then attach the caliper?
Or if it has a brake mounting hole already?

If the former, it's really not something I'd be doing myself, there are some forks (notably track forks) where it WILL weaken the crown.
If the latter, the brakes should just go straight on as per the video.

In fact from your original picture, I'm certain that's a rear brake caliper you've got there. Have you got both calipers? The front one has a noticeably longer bolt.

[gaz]

Zooming in on steverod's original pic it appears that the rear of the fork is undrilled. There's no obvious provision for disc, canti or other braze-on brakes.

I'm wondering whether the forks are designed for track use, or use on road in an appropriate non-UK market?

[steverod]

Thanks for the replies. Yes, it's a track bike with no holes for a front brake. The one brake I bought was sold as a front track bike brake. I'll go back and check.

[Mike Sales]

I'm wondering whether the forks are designed for track use, or use on road in an appropriate non-UK market?

Would track forks have the crown front drilling?

[steverod]

The company sell the same brake front or back. The only difference is the length of cable supplied.