Drill my old aluminum frame for di2 - yay or nay?

[apple]

Old aluminum CAAD10. Want to convert it to di2 with my old ultegra di2 that I just pulled off my other bike. Looking at a 1x11 setup so no FD hole (maybe in the future...).

With a seat tube internal battery, looks like I could do it with two dremel holes. One on the downtube NDS a couple inches back from the head tube and one at the rear of the chainstay.

Holes would be slowly enlarged with dremel to be just large enough to fit the di2 weatherproof grommet. Looking at the inside of the frame with bottom bracket removed, looks like a straight shot down the downtube, from the BB up to internal seatpost battery, and from BB to end of chainstay.

I wouldn't drill carbon, but feel safer punching a couple holes in aluminum in what appear to be the standard hole locations for di2, which are locations chosen by people smarter than me to be where I assume the frame stress is minimized.

What do you think?

[YesNdeed]

My welder/frame builder buddy, who worked under local builder Dave Porter, advises against putting any holes in frames, even for bottle cages, as there are usually reinforcements applied to any such modifications by the manufacturer. But I'm now curious enough, myself, to find a Di2 CAAD 10 and run my fingers into the battery/servo ports to see if I can feel the said reinforcements. As a rule of thumb, if I can't afford to throw something in the trash, then I don't take a drill or saw to it. My $0.02.

[FlashUNC]

Fwiw, my Rock Lobster that Paul did for EPS with some holes drilled in it has no reinforcements at the hole sites. He's using a fairly beefy alu tubing for my bike, but if you're careful and keep an eye on it, I don't see it causing any issues.

[apple]

I feel you on that. Luckily CAAD10s seem to be going pretty cheap, so wouldn't be a huge loss if something went horribly wrong. My real concern is going on a ride and having something snap on the frame causing catastrophic injury...

[oldpotatoe]

Old aluminum CAAD10. Want to convert it to di2 with my old ultegra di2 that I just pulled off my other bike. Looking at a 1x11 setup so no FD hole (maybe in the future...).

With a seat tube internal battery, looks like I could do it with two dremel holes. One on the downtube NDS a couple inches back from the head tube and one at the rear of the chainstay.

Holes would be slowly enlarged with dremel to be just large enough to fit the di2 weatherproof grommet. Looking at the inside of the frame with bottom bracket removed, looks like a straight shot down the downtube, from the BB up to internal seatpost battery, and from BB to end of chainstay.

I wouldn't drill carbon, but feel safer punching a couple holes in aluminum in what appear to be the standard hole locations for di2, which are locations chosen by people smarter than me to be where I assume the frame stress is minimized.

What do you think?

NOT aluminum, ask a frame builder who deals in such things but I 'plumbed' my kinda knackered MXLeader for EPS almost 2 years ago..have ridden it a LOT and have seen no issues at all. 4 holes for me, external battery. right hand side, upper part of down tube, under downtube bottle cage, by front der and on top of RH chainstay..but aluminum, don't know.

[apple]

Fwiw, my Rock Lobster that Paul did for EPS with some holes drilled in it has no reinforcements at the hole sites. He's using a fairly beefy alu tubing for my bike, but if you're careful and keep an eye on it, I don't see it causing any issues.

Thanks for the data. Any opinions on drilling a hole straight into the frame versus drilling at an angle to ease the transition of the wire into the frame? My carbon frame built for di2 has the holes angled, but it feels safer with this to just go straight in.

[stien]

Just to correct you, you'll need a hole big enough for the cable connector, not the grommet.

I haven't created holes but I sure have enlarged holes in carbon for di2 installs with external batteries.

Go with a double front. Perhaps hog the BB cable guide screw hole out. If you're going electric you might as well go for it.

[oldpotatoe]

Just to correct you, you'll need a hole big enough for the cable connector, not the grommet.

I haven't created holes but I sure have enlarged holes in carbon for di2 installs.

Go with a double front.

Di2 are 6mm, EPS are 7mm..connector. I drilled straight in, then angled the hole with the drill bit a little. aft for rear der wire, forward for interface wire. straight in for front der and 3 wres into frame under bottle cage. 5/16 inch drill bit for 7mm.

[54ny77]

interesting question. caad tubes are mighty big, but thin.

i'd be a bit paranoid about it, myself, but maybe that's what they do at factory already so no big deal.

there's a ton of caad folks on the ww forum, you might check there to see what they've done.

[eBAUMANN]

yay

drill the headtube instead of the downtube if concerned about tube wall thickness

[stien]

yay

drill the headtube instead of the downtube if concerned about tube wall thickness

What about the steerer? Enough room for a cable to get by?

[apple]

How "thin" is "too thin"? I don't have much experience with bike building and such.

[batman1425]

There's a guy that sold a 58cm CAAD10 that he did this to over on Slowtwitch. Took a while to sell and ended up getting around $275 +shipping for a frame/fork - don't know the actual deal but that was the last advertised price before it sold. So if you decide to go that way - you can expect resale to take a big hit.

Can't comment on safety - but if it was my bike I would say not a good idea. Just not worth the risk.

[zap]

edit

Old aluminum CAAD10.

With a seat tube internal battery, looks like I could do it with two dremel holes. One on the downtube NDS a couple inches back from the head tube and one at the rear of the chainstay.

What do you think?

I wouldn't do it to an al frame.

[eBAUMANN]

What about the steerer? Enough room for a cable to get by?

yes, plenty, its a pretty common spot these days, a lot of production frames are doing it. van dessel has a couple models that i know of, many steel builders have done it, its a thing. steerer has PLENTY of room around it even in a standard 1-1/8 headtube. non issue.

just one example:

http://www.feathercycles.com/staging/wp-content/uploads/2014/05/SHOW-029-682x1024.jpg

how thin is too thin?

well, generally you do not want to make a hole in a tube that is not then being reinforced with another piece of metal either welded or brazed around said hole. just drilling a hole in any tube (steel or alloy) is kinda sorta rolling the dice. its introducing a point of failure, a place for a crack to start. it might look smooth to your eye but the edge of a drilled hole is actually quite jagged from a material perspective. the thinner the tube, the more likely it is to crack where you drill.

so, that said, if it were my frame, i would not be drilling a hole in the DT, i would go into the headtube (thicker, less stress), out at the seat tube (less stress in ST), and then the chainstay (much thicker tubing than main triangle, but still sees a decent amount of stress).

bottom line, there is a chance that a hole anywhere in the frame could generate a crack. drill at your own risk.

[fa63]

I had a custom aluminum frame crack at the location of a Di2 hole on the downtube, for what it is worth. The builder built me a new frame immediately, this time without any holes (at my request, as I didn't want to deal with the possibility again).

[bicycletricycle]

nope

[Fatty]

As an owner of an older Cannondale aluminium I would be very hesitant to drill any hole in the frame. That in my opinion would just be a starting point for a crack and fail.

[cmbicycles]

I wouldn't do it on my own bike or for anyone really. Tubes are quite thin and not worth the risk for me. On older Cannondales (if memory serves) they drilled two holes for shifter bosses and had a bolt go through to connect them. Much thicker tubing back then though.

If you had your mind made up to do it though... I can't tell by Internet pictures, are the downtube cable stops welded on or riveted on a caad 10? If welded, you could potentially file flat and drill through the stop as it would be a bit thicker there. If rivited, there is already a hole there you might be able to use... may involve cutting and soldering the wire if you didn't want to make the hole bigger.

[apple]

Alright thanks all.

So the problem seems to be leaning more toward the fact that it's a CAAD with thinner tubing than the actual drilling. So maybe if I had a frame with thicker tubing it might be okay?

[Fatty]

Some Cannondale love.

[tigoat]

I don稚 know much about aluminum frames but I know that there are tons of steel, Ti, and carbon frames out in the field with water bottle mount holes flat out drilled and without being reinforced, which I absolutely hate. How often do we hear about those non-reinforced water bottle mount holes crack? With a large filled water bottle in place, these water bottle mounts must take a lot of stress, especially going over some bumpy roads. Take a look at those water bottle mounts on your particular aluminum frame to see if they are reinforced or not, as that should give you some idea how feasible it is to have some additional non-reinforced holes on your frame.

How did you get such a cool screen name?

[jimcav]

leave the CS alone and run that derailleur cable out the BB on the underside--use some silicone caulk in a few key spots and it will barely be noticeable.
jim

[bicycletricycle]

good point, those water bottle holes tend to be in lower stressed parts of the tube.

I don稚 know much about aluminum frames but I know that there are tons of steel, Ti, and carbon frames out in the field with water bottle mount holes flat out drilled and without being reinforced, which I absolutely hate. How often do we hear about those non-reinforced water bottle mount holes crack? With a large filled water bottle in place, these water bottle mounts must take a lot of stress, especially going over some bumpy roads. Take a look at those water bottle mounts on your particular aluminum frame to see if they are reinforced or not, as that should give you some idea how feasible it is to have some additional non-reinforced holes on your frame.

How did you get such a cool screen name?

[livingminimal]

I was wanting to drill out my Stinner cross bike for Di2...when I sent it back to them they said unequivocally, no dice...maybe I should have sent it to Eric B....

[shovelhd]

Is the CAAD10 BB30? If so, how are you going to deal with the B junction? You could use an externally mounted one, but if you want to use an internal one you're going to need a pretty big hole in the BB shell.

[Peter P.]

Alright thanks all.

So the problem seems to be leaning more toward the fact that it's a CAAD with thinner tubing than the actual drilling. So maybe if I had a frame with thicker tubing it might be okay?

It's quite possible that OEM frames coming from the factory with Di2 holes in them are using thicker tubes where the entry and exit holes are. We don't know, but the engineers may have already considered this issue.

Sometimes it's what you DON'T see that makes the difference.

[aramis]

I did the external di2 wiring on my Van Dessel and if you do it well it's not bad at all.

Shimano sells covers to hide the wiring and you just place the battery behind the water bottle. No big deal.

[SleepyCyclist]

http://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=109014&start=90

In case OP hasn't found this thread already.

m

[unterhausen]

helicopter tape or gorilla repair tape makes for a really clean external install. No way in hell I would drill that frame for someone that wasn't known to eat live kittens for breakfast.

http://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=109014&start=90

In case OP hasn't found this thread already.

m

tube doesn't look as thin as some I've seen, but the hole quality is horrific. As long as he monitors for cracks, it's not likely to kill him

[apple]

http://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=109014&start=90

In case OP hasn't found this thread already.

m

This is helpful, thank you.

[nm87710]

FYI...drilled a CAAD7 HT & BB for a SRM wiring harness and rode without issue for 30K miles. HT and BB were plenty thick. Wouldn't drill the TT or DT though - too thin.

Good Luck!

[apple]

Someone emailed me about a Gaulzetti and got me thinking. Does anyone happen to have a good 60cm handmade metal bike frame of some sort that's set up for di2?

Maybe a 58-60cm Gaulzetti/Zanconato/Speedvagen/Spooky/Firefly frame?

[apple]

FYI...drilled a CAAD7 HT & BB for a SRM wiring harness and rode without issue for 30K miles. HT and BB were plenty thick. Wouldn't drill the TT or DT though - too thin.

Good Luck!

I'm going to remove the fork and see what kind of clearance I have in the HT. That is a solid idea.

[CSTRider]

Although i think putting holes in aluminum is risky, have to wonder if you couldn't just reinforce the drilled area first by epoxying a small carbon fiber patch over the area you were planning to drill. Apply patch, wait until hard, and then drill and carefully file hole edges smooth ... done.