I'm building a new Sunday Model C and discovered that the Sunday 24.1 forks that wanted to use have no brake hole.
However you feel about front brakes on a 24 (or brakes in general lately) I would like to run front brakes.
Has anyone ever drilled a brake hole in forks?
Am I in danger of damaging the structural integrity of the forks?
What size is the hole?
Does anyone know of 24" forks with brake posts?
-Mark
Full Version: Drilling forks for brakes?
I have drilled forks before. Use a drill press as it's important to get the whole straight.
I had no trouble with strength on the forks I done. Factory holes are done the same way so I don't see a problem.
I had no trouble with strength on the forks I done. Factory holes are done the same way so I don't see a problem.
Structural integrity should not be a problem as long as you are drilling the hole lower than the "imaginary arc" the 2 fork legs form when welded to the headtube.
I wouldn't be too keen on drilling a hole in the middle of that arc.
Hole Diameter ?
Drill a 1/8th pilot hole first , followed by a hole with just enough clearance to slide your front brake in & out easily without damaging the threads.
No need to drill for a precision fit or the old generic "factory" sloppy fit , if you already have the brakes reverse engineer the diameter from there.
Take your time , having the forks protected & secured below a drill press would be preferable to using a hand drill , either way clamp the forks to something solid.
Use a center punch to mark the pilot hole.
Brake posts can always be brazed welded onto forks , if you can find someone who is genuinely up to the job.
You are possibly opening up a giant can of worms by taking this route , despite thinking it is a good idea at first.
NEVER EVER try a doing a front brake Pott's mod like this.
It is physically impossble to do with the 2nd gen plugged Bottema's , no clearance inside for the brake cable to bend smoothly.
& when you replace the forks with first gen unplugged Bottema's , that have more internal clearance in the headtube , you end up with a
brake cable & clamping nightmare. The setup worked great without using the stainless steel cable ties I prefer to finish off the job ,
but I _really_ wouldn't recommend trying to duplicate it , it may have been possible to improve on...who knows it's been removed now.
That's not to discourage anyone from designing & fitting unique or novel brake setups to their bikes. Innovation & creativity are part of BMX's roots.
It really seemed like a good idea at the time....honestly.
JB
I wouldn't be too keen on drilling a hole in the middle of that arc.
Hole Diameter ?
Drill a 1/8th pilot hole first , followed by a hole with just enough clearance to slide your front brake in & out easily without damaging the threads.
No need to drill for a precision fit or the old generic "factory" sloppy fit , if you already have the brakes reverse engineer the diameter from there.
Take your time , having the forks protected & secured below a drill press would be preferable to using a hand drill , either way clamp the forks to something solid.
Use a center punch to mark the pilot hole.
Brake posts can always be brazed welded onto forks , if you can find someone who is genuinely up to the job.
You are possibly opening up a giant can of worms by taking this route , despite thinking it is a good idea at first.
NEVER EVER try a doing a front brake Pott's mod like this.
It is physically impossble to do with the 2nd gen plugged Bottema's , no clearance inside for the brake cable to bend smoothly.
& when you replace the forks with first gen unplugged Bottema's , that have more internal clearance in the headtube , you end up with a
brake cable & clamping nightmare. The setup worked great without using the stainless steel cable ties I prefer to finish off the job ,
but I _really_ wouldn't recommend trying to duplicate it , it may have been possible to improve on...who knows it's been removed now.
That's not to discourage anyone from designing & fitting unique or novel brake setups to their bikes. Innovation & creativity are part of BMX's roots.
It really seemed like a good idea at the time....honestly.
JB
Dont worry about structural integrity issues. --No eppect. I did this a long time ago on a fork and no problem. As for the size of the hole,take a drillbit and use the rear brake bridge as a reference for the size
[
quote name='MarkFitzpatrick' date='Oct 31 2009, 08:45 PM' post='886512']
I'm building a new Sunday Model C and discovered that the Sunday 24.1 forks that wanted to use have no brake hole.
However you feel about front brakes on a 24 (or brakes in general lately) I would like to run front brakes.
Has anyone ever drilled a brake hole in forks?
Am I in danger of damaging the structural integrity of the forks?
What size is the hole?
Does anyone know of 24" forks with brake posts?
-Mark
[/quote]
[
quote name='MarkFitzpatrick' date='Oct 31 2009, 08:45 PM' post='886512']
I'm building a new Sunday Model C and discovered that the Sunday 24.1 forks that wanted to use have no brake hole.
However you feel about front brakes on a 24 (or brakes in general lately) I would like to run front brakes.
Has anyone ever drilled a brake hole in forks?
Am I in danger of damaging the structural integrity of the forks?
What size is the hole?
Does anyone know of 24" forks with brake posts?
-Mark
[/quote]
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