View Full Version : Drilling holes for weight reduction?
bradberry00
06-01-07, 12:34 PM
I'm a hot rod guy, bikes are me cheap and enjoyable alternative. In the hot rod/automobile racing world it was and is common to drill holes in frames, axles, etc. to reduce weight. Is this kosher in the world of bikes? Can frames and Forks be drilled? what areas should you avoid drilling to avoid strength issues? I just think it would look cool on my planned fixed vintage project.
thanks,
David
Blue Jays
06-01-07, 12:39 PM
Drilling the daylights out of parts was all the rage back in the 1970's and early-1980's.
Drilling a frame and or fork is a big bad idea. a frame and fork are all load bearing structures, and are designed with minimal extra, all parts are doing their work. putting holes all over the place will severely weaken your ride, and put you in danger!!! Like was mentioned, they did it back in the day, but on things like levers, shifters, sprockets, etc- parts that wouldnt put your life in danger if they failed
~Steve
there are better ways of getting that old school hot rod look.
thatcher
06-01-07, 12:50 PM
drillium! i was actually thinking about drilling my lugs a bit for looks but it would take some carfull planning and exicution. i think the tubes would be too thin for that though. also the holes would allow water to get into the frame so i was only thinking the lugs at the seat post and around the headset would be acceptable for that treatment.
jeremyb_nz
06-01-07, 03:59 PM
Trials guys still drill their rims to save weight, but frames and forks these days are on the limit as they are, drilling them out would be suicide!
kubacola
06-02-07, 03:50 PM
You can still purchase drilled chainrings (have a sugino) and drilled looking cogs (have a surly). Have seen very cool drilled bmx brake levers- drilled at the mounting clamp. The miche supertype seatpost has a look similar to drilled stuff although its something different. Some chains have holes in the chainplates. There are some brakes that look lightwieght- sram rval (i think) and i think johnny cycles is the maker of the drilled looking frame, the picture of which Im attaching. Seome custom made, if i remeber well, dropouts also.... and other things.
wethepeople
06-02-07, 04:04 PM
My personal favorite:
http://img.photobucket.com/albums/v419/wethepeople101/albin1.jpg
kubacola
06-02-07, 05:41 PM
awesome! :eek:
Surferbruce
06-02-07, 07:05 PM
i've got a pic somewhere of merckx on a gorgeous bike with fully drilled campy everything, i so wonder where that bike's hanging up.
SamHall
06-03-07, 09:50 PM
There have been some awesome track bikes built with drilled frames and forks for aero benefits, but they also brazed tubes in the holes to get the strength back (like the Jonny bike). the end result was a bike that was very fast, looked very cool, but was heavier than the same bike sans holes.
filtersweep
06-03-07, 11:16 PM
I'd like to see the physics there- drilling would likely only INCREASE air resistence.
There have been some awesome track bikes built with drilled frames and forks for aero benefits, but they also brazed tubes in the holes to get the strenth back (like the Jonny bike). the end result was a bike that was very fast, looked very cool, but was heavier than the same bike sans holes.
SamHall
06-04-07, 04:41 PM
I'd like to see the physics there- drilling would likely only INCREASE air resistence.
The holes I'm talking about were running front to back, not side to side like on the Jonny bike.
mentat6059
06-07-07, 10:45 PM
what can happen if you get a little too excited with your drilling
http://web.archive.org/web/20060819020323/http://www.fyxomatosis.com/images/campy_drilledpost.jpg
how much weight are you going to save anyway? spend the time training a bit more, or work on getting your posture a bit more aero and you'll be better off than if you had a drilled out (weak) part that saved you 8 grams. especially if the chainring folds on a sprint or the seatpost buckles and sends you to the hospital.
chevy42083
06-08-07, 10:57 AM
I think it's more of the look, and the idea than the actual benefit ;)
And yeah, drilled and counter-sunk brake levers, chainrings, and shifters look cool. Also seen some lugs with decorative holes... although probably done before assembly.
My personal favorite:
http://img.photobucket.com/albums/v419/wethepeople101/albin1.jpg
why not just use one of these?
http://www.geocities.com/RodeoDrive/Boutique/2741/doiley2226.jpg
Lamplight
06-25-07, 02:53 PM
You can still purchase drilled chainrings (have a sugino) and drilled looking cogs (have a surly). Have seen very cool drilled bmx brake levers- drilled at the mounting clamp. The miche supertype seatpost has a look similar to drilled stuff although its something different. Some chains have holes in the chainplates. There are some brakes that look lightwieght- sram rval (i think) and i think johnny cycles is the maker of the drilled looking frame, the picture of which Im attaching. Seome custom made, if i remeber well, dropouts also.... and other things.
Are those Sugino cranks old or can you still get them like that? I really love the old slender cranks.
Tear along the dotted line.
The biggest frame "drillout" is already in place: the hollow center space in the middle of the frame tubes.
what can happen if you get a little too excited with your drilling
http://web.archive.org/web/20060819020323/http://www.fyxomatosis.com/images/campy_drilledpost.jpg
what's up with the campy banner behind the last photo?
zonatandem
06-26-07, 04:51 PM
In the mid-70s a bit lighter but rode like a very wet sponge!
Homebrew01
07-06-07, 09:01 AM
I guess you could do a little decorative countersinking on lugs if it's not very deep, then paint with a contrasting color. i wouldn't drill components unless I had a milling machine and rotary table to get them all in the right spot. Nothing worse looking than "home-made" drilling
Bobatin
07-06-07, 09:22 AM
They stopped drilling components because they found in the wind tunnel that there was greater drag created by all the drilled holes than what was gained through weight loss.
hockeyteeth
07-06-07, 05:55 PM
what's up with the campy banner behind the last photo?
That's Andy White from Fyxomatosis.com. He makes jerseys with a Campy-esque logo using the words "trackcvnt" instead.
kraftwerk
07-06-07, 06:00 PM
The wind tunnel test canned the Pantagraphic cuts and drilled holes. I think it looks pretty cool --- and retro!! I have some parts that have been "holed"
Moochers_Dad
07-06-07, 06:51 PM
http://img73.imageshack.us/img73/3411/drilledchainringfh4.jpg
It's only valid if the heavy dust caps are removed too. :)
Moochers_Dad
07-06-07, 06:59 PM
http://www.raydobbins.com/molteni_replica/photo16.jpg
http://www.raydobbins.com/molteni_replica/photo18.jpg
http://www.raydobbins.com/molteni_replica/photo27.jpg
optimator
07-08-07, 08:10 PM
The color! The cloth tape!! The shift lever!!! (Look carefully - oh la la!) - O
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