Framebuilders - Drilling holes for weight reduction?

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

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.

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.

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!

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.

My personal favorite:
http://img.photobucket.com/albums/v419/wethepeople101/albin1.jpg

awesome! :eek:

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.

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.

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.

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.

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.

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

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?

In the mid-70s a bit lighter but rode like a very wet sponge!

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

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.

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.

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"

http://img73.imageshack.us/img73/3411/drilledchainringfh4.jpg

It's only valid if the heavy dust caps are removed too. :)

http://www.raydobbins.com/molteni_replica/photo16.jpg
http://www.raydobbins.com/molteni_replica/photo18.jpg
http://www.raydobbins.com/molteni_replica/photo27.jpg

The color! The cloth tape!! The shift lever!!! (Look carefully - oh la la!) - O

To get rid of a lot of unnessecary weight you can drill multiple holes in your handle bars under where the grips go. i've done it!... hardly any strength is compromised and they are not noticeable.. also cut off all that seat post shoved in the frame.. you can lose a couple pounds by doing this..! DO NOT cut holes in frame... trust me.. it doesnt workk (experience) . Another place you an do it is after you cut the post drill holes in it as well.. again no strenght compromised. :D Get rid of that peice o' **** gyro.! and the brakes if you feel safe doing it.. get plastic pedals.. and titantium axles if you can afford em.. there worth it.

Factory drillium:
http://os2.dhs.org/~john/zeus-drillium.jpg

Homemade drillium:
http://os2.dhs.org/~john/campy-drillium.jpg

I have a set of Zeus 2000 cranks that have no drillium at all. Zeus went crazy on some versions, they milled big slots in the arms.

Just sold a rear derailleur on ebay and the cage was drilled out.

I guess if the OP carried through with drilling out his frame, he's no longer with us.

from cycling news:

http://cyclingnews.com/photos/2009/tech/probikes/carlos_sastre_cervelo_testeam_s3/18rotorchainset.jpg

Drilled on all 3 axes

Some of that stuff looks pretty cool. OTOH, some of it looks like body piercing gone wrong.

from cycling news:
Drilled on all 3 axes
Hopefully that's a show bike, or will see a very limited number of miles

Some of that stuff looks pretty cool. OTOH, some of it looks like body piercing gone wrong.

Perfect analogy. :thumb: Exactly the same sort of "what were they thinking?"

To get rid of a lot of unnessecary weight you can drill multiple holes in your handle bars under where the grips go. i've done it!... hardly any strength is compromised and they are not noticeable.. also cut off all that seat post shoved in the frame.. you can lose a couple pounds by doing this..! DO NOT cut holes in frame... trust me.. it doesnt workk (experience) . Another place you an do it is after you cut the post drill holes in it as well.. again no strenght compromised. :D Get rid of that peice o' **** gyro.! and the brakes if you feel safe doing it.. get plastic pedals.. and titantium axles if you can afford em.. there worth it.

That is a very bad idea. How is the seatpost's strength not important? This may work on 80's bike boom bikes that basically had galvanized pipe for seatubes, but anything modern (even if it looks retro) is probably near it's limits, as everyone has said. And brakes are often taken off for major climbs with no downhill at all (along with the other chainring, a few gears in the back, bottle cages, etc.). And plastic pedals are a joke, I wonder how well they hold up in a sprint, unless you are talking about disposable pedals.

And there is some truth to drilling helping with aerodynamics, but not true drilling. Dimpling is what helps aero.
Practical versions of things in this post:

Get a carbon seatpost, or a titantium or even steel if that's your bike's theme. Modern ones are plenty light enough. As for brakes, the new campy super record skeleton brakes are as light as they come, being made from carbon fiber and having very little material (their aluminum chorus brakes have the same design, just in aluminum and different bearings). And as for pedals, composite (yes, some plastic but carbon fiber as well) pedals with titantium shafts.