Drilling carbon fiber fork?
01-23-11, 03:25 PM
#1
Senior Member
Thread Starter
Join Date: Jan 2010
Location: Bay Area, CA
Posts: 270
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Drilling carbon fiber fork?
Does anyone have any experience drilling a carbon fork so you can mount a brake? Do LBS offer this service? Or should I not stress about it and just do it myself?
01-23-11, 03:39 PM
#3
Senior Member
Thread Starter
Join Date: Jan 2010
Location: Bay Area, CA
Posts: 270
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
It's a track fork, and wasn't drilled for a brake.
Last edited by BmoreDrew; 01-23-11 at 03:45 PM.
01-23-11, 04:19 PM
#4
Bianchi Goddess
Join Date: Apr 2009
Location: Shady Pines Retirement Fort Wayne, In
Posts: 27,858
Bikes: Too many to list here check my signature.
Mentioned: 192 Post(s)
Tagged: 2 Thread(s)
Quoted: 2930 Post(s)
Liked 2,923 Times
in
1,491 Posts
I would not drill it and I doubt a shop would do it, they would be liable if it broke. track forks usually have a tight clearance between the tire and crown. is there room for a brake that will be below the bridge?
__________________
“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk
“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk
01-23-11, 04:35 PM
#6
Guest
Join Date: Jul 2008
Location: Grid Reference, SK
Posts: 3,768
Bikes: I never learned to ride a bike. It is my deepest shame.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 6 Times
in
6 Posts
New fork time.
f you are not convinced perhaps contact the manufacturer and see if they think it is a good idea. I'll bet real money that they tell you it certainly is not a good idea.
Also the tight clearance on a racing track fork might make it hard to fit a brake between the headset and tire and still be able to properly line up the pads on the rim.
f you are not convinced perhaps contact the manufacturer and see if they think it is a good idea. I'll bet real money that they tell you it certainly is not a good idea.
Also the tight clearance on a racing track fork might make it hard to fit a brake between the headset and tire and still be able to properly line up the pads on the rim.
01-23-11, 04:40 PM
#7
Guest
Posts: n/a
Mentioned: Post(s)
Tagged: Thread(s)
Quoted: Post(s)
A solution:
https://www.tracksupermarket.com/inde...roducts_id=330
Drilling out a carbon fork is not smart.
https://www.tracksupermarket.com/inde...roducts_id=330
Drilling out a carbon fork is not smart.
01-23-11, 04:45 PM
#8
Senior Member
Join Date: Sep 2009
Location: Up
Posts: 4,695
Bikes: Masi, Giant TCR, Eisentraut (retired), Jamis Aurora Elite, Zullo, Cannondale, 84 & 93 Stumpjumpers, Waterford, Tern D8, Bianchi, Gunner Roadie, Serotta, Serotta Duette, was gifted a Diamond Back
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 305 Post(s)
Liked 2,038 Times
in
604 Posts
get a new fork.
01-23-11, 04:54 PM
#9
Dough Mestique
Join Date: Feb 2009
Posts: 355
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
You could try to drill a hole in the fork. However, depending on your skill level and the quality of your tools, there's a chance you'd destroy the fork.
Even if you do successfully drill a hole in the fork, it won't be braced or supported in any way to withstand the loads caused by braking.
Sell this one, and buy a new fork.
BL
Even if you do successfully drill a hole in the fork, it won't be braced or supported in any way to withstand the loads caused by braking.
Sell this one, and buy a new fork.
BL
01-23-11, 05:36 PM
#10
Senior Member
Join Date: Aug 2008
Location: San Francisco
Posts: 1,332
Bikes: 1989 Team Miyata, 1989 Miyata 1400, 1989 Miyata 1400, 1986 Miyata 610, 2007 Specialized Stumpjumper Hardtail
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
A solution:
https://www.tracksupermarket.com/inde...roducts_id=330
Drilling out a carbon fork is not smart.
https://www.tracksupermarket.com/inde...roducts_id=330
Drilling out a carbon fork is not smart.
01-23-11, 06:36 PM
#11
Senior Member
Thread Starter
Join Date: Jan 2010
Location: Bay Area, CA
Posts: 270
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
the thought was to just drill the plug out, which tells me its their same fork they use on roadie bikes, just plugged and painted.. or rather, not drilled and painted. but perhaps its time for a wound up fork
01-23-11, 07:31 PM
#12
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,096 Times
in
742 Posts
Look inside the fork crown to see if there are already holes that have just been covered and painted on the outside. If the holes are there just open them up. If not, new fork time.
01-23-11, 07:45 PM
#13
Senior Member
Join Date: Dec 2006
Location: So Cal
Posts: 2,678
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Rather than guess I'd contact Fuji first and ask some questions and find out if it is finished inside and just plugged.
I'm sure someone will tell you what's going on with that fork or also talk to some track guys that may know about it.
I'm sure someone will tell you what's going on with that fork or also talk to some track guys that may know about it.
__________________
It may not be fancy but it gets me were I need to go.
https://www.jtgraphics.net/cyclist_bicycles.htm
It may not be fancy but it gets me were I need to go.
https://www.jtgraphics.net/cyclist_bicycles.htm
01-23-11, 08:16 PM
#14
Senior Member
Join Date: Mar 2009
Posts: 339
Bikes: 1981 Sekai 1500 Mixte, 1974 Schwinn Le Tour Mixte, 1984 Peugeot Mixte, 1975 Gitane Grand Sport Deluxe Mixte, Motobecane Nomade II Mixte, 2001 Trek 520, 1974 Peugeot UO-18 Mixte
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
do not drill it. 99% of the time, drilling anything carbon is a bad thing. You need a new fork.
01-24-11, 12:47 AM
#16
Senior Member
Join Date: Mar 2010
Location: City of Brotherly Love
Posts: 1,562
Bikes: Raleigh Companion, Nashbar Touring, Novara DiVano, Trek FX 7.1, Giant Upland
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 22 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The FC-770 fork has carbon legs bonded to an aluminum crown. It is also used in applications that have brakes.
01-24-11, 01:56 AM
#17
Senior Member
Join Date: Oct 2009
Location: Minneapolis
Posts: 2,470
Bikes: -1973 Motobecane Mirage -197? Velosolex L'Etoile -'71 Raleigh Super Course
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
Clamp the fork securely to the table of a quality drill press and use a good sharp bit to drill the hole. Carbon-fiber sailboat parts get drilled and routed all the time, and they take stresses far beyond anything a bike fork takes. Do try to figure out where the neutral axis of the stress lines are and try to center the hole on this; but as far as drilling CF, there's nothing magical about it.
drill baby drill
drill baby drill
01-24-11, 02:50 AM
#18
Riding
Join Date: Dec 2010
Location: Bend, Oregon
Posts: 1,909
Bikes: Motobecane Fantom Cross Pro; Motobecane Nemesis Pro
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
This is a question I would take to the manufacturer. Carbon fiber can be drilled and it looks like the fork was designed for it. But I would personally let a pro handle it.
01-24-11, 08:25 AM
#20
Senior Member
Join Date: May 2005
Location: SFBay
Posts: 2,334
Bikes: n, I would like n+1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 127 Post(s)
Likes: 0
Liked 133 Times
in
108 Posts
If you had to drill through carbon I'd say no. In this case, since it seems you'll be going through aluminum, you *might* be ok. The safe option is to buy a new fork. That said, if I were to do this I would jig it on a good drill press, hit it with a starter bit, then a much smaller diameter bit, then the proper size. You'll want it to be VERY well centered. I would also call the manufacturer first. Make sure to support the back side with something a bit softer than the metal drill press table.
01-24-11, 10:05 AM
#21
Senior Member
Join Date: Mar 2008
Posts: 8,688
Mentioned: 46 Post(s)
Tagged: 0 Thread(s)
Quoted: 1074 Post(s)
Liked 295 Times
in
222 Posts
While I agree that there's nothing inherently magical about how to work with CF, the sweeping assumptions of the statement above just astounds me. The loads might certainly be bigger on a sailboat, but the stresses can be just as high or higher on a bike part.
01-24-11, 10:55 AM
#22
Senior Member
Join Date: Oct 2009
Location: Minneapolis
Posts: 2,470
Bikes: -1973 Motobecane Mirage -197? Velosolex L'Etoile -'71 Raleigh Super Course
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
Yes, absolutely. Please forgive me, I'm only a shadetree engineer and not a school-trained one. Of course there's a difference between stressing and loading, I would have seen that if I'd thought it through one or more times. Thanks for pointing out that there's a difference.
01-24-11, 02:19 PM
#23
Senior Member
Join Date: Mar 2008
Posts: 8,688
Mentioned: 46 Post(s)
Tagged: 0 Thread(s)
Quoted: 1074 Post(s)
Liked 295 Times
in
222 Posts
Yes, absolutely. Please forgive me, I'm only a shadetree engineer and not a school-trained one. Of course there's a difference between stressing and loading, I would have seen that if I'd thought it through one or more times. Thanks for pointing out that there's a difference.
All I'm saying is that high-end bicycles can have parts of their structures pretty darn borderline engineered in the quest for weight and design advantages. The fact that the vehicle as a whole doesn't see big loads doesn't tell you anything about the design margins, whether there's enough to allow for the drilling of a hole or not.
01-24-11, 03:53 PM
#24
It's got electrolytes!
Join Date: Aug 2009
Posts: 1,388
Bikes: Self-designed carbon fiber highracer, BikesDirect Kilo WT5, Pacific Cycles Carryme, Dahon Boardwalk with custom Sturmey Archer wheelset
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Of course you can drill the fork.
There's a reason why brakes are mounted in this way and that reason is that fork crowns need to be overbuilt to withstand the stresses of riding anyway. So by also mounting the brake there you kill two birds with one stone.
I wonder what the nanny mechanics here would have said to the first bloke that ever mounted a brake in this way. Clearly he didn't have a proper fork marketed and advertised to be suitable for drilling, but he did it anyway and it worked just as it will here.
There's a reason why brakes are mounted in this way and that reason is that fork crowns need to be overbuilt to withstand the stresses of riding anyway. So by also mounting the brake there you kill two birds with one stone.
I wonder what the nanny mechanics here would have said to the first bloke that ever mounted a brake in this way. Clearly he didn't have a proper fork marketed and advertised to be suitable for drilling, but he did it anyway and it worked just as it will here.
01-24-11, 04:03 PM
#25
Riding
Join Date: Dec 2010
Location: Bend, Oregon
Posts: 1,909
Bikes: Motobecane Fantom Cross Pro; Motobecane Nemesis Pro
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Of course you can drill the fork.
There's a reason why brakes are mounted in this way and that reason is that fork crowns need to be overbuilt to withstand the stresses of riding anyway. So by also mounting the brake there you kill two birds with one stone.
I wonder what the nanny mechanics here would have said to the first bloke that ever mounted a brake in this way. Clearly he didn't have a proper fork marketed and advertised to be suitable for drilling, but he did it anyway and it worked just as it will here.
There's a reason why brakes are mounted in this way and that reason is that fork crowns need to be overbuilt to withstand the stresses of riding anyway. So by also mounting the brake there you kill two birds with one stone.
I wonder what the nanny mechanics here would have said to the first bloke that ever mounted a brake in this way. Clearly he didn't have a proper fork marketed and advertised to be suitable for drilling, but he did it anyway and it worked just as it will here.