Drain Hole Drilling

[RobinDuraAce]

Hi Guys,
My girlfriend uses a wheelset from a local wheel builder in Germany and I think he uses Wheelsfar Rims or sort of. Completely fine with the wheelset, but the rims have no drain holes for the water getting out of the rim. So I want to drill this on my own. Because with a tubeless set up, I need to remove the valve and lose all the milk, this just sucks

Have somebody any experience with this?
My initial thought was around 2-2,5mm diameter and on both sides of the rim in the opposite position of the valve. And around 20mm under the the rim/tire.

And after this, a little bit glue around the hole.

Her weight is around 55 kilos and it is a road wheelset, if this helps

Thanks for your help!

[Lelandjt]

I used to drill all my Light Bicycle rims before they came with drain holes. 2mm is a good size. I never used glue or anything to seal the cut, just use a good drill bit and make a clean hole. Before drilling I'd look at a cross section of the rim and try to get the hole as close as I could to the horizontal structure (rim bed?). I did 2 holes on opposite sides and opposite ends of the rim from each other, both 1/4 way around from the valve.

[RobinDuraAce]

Okay thanks!
My English is not the best, what do you mean exactly with opposite ends of the rim form each other?
So in total 4 holes per rim?
2 on the drive train and 2 on the non drive train side?
And the position at 3 and 9 o clock? ( valve is 12)

[RobinDuraAce]

Double post

[Mr.Gib]

@RobinDuraAce, your English is great.

...both 1/4 way around from the...

This implies just 2 holes.

And if I understand the description correctly, one on each side of the rim (drive side and non-drive side), and 180 degrees opposite each other. The locations chosen are 90 degrees from the valve hole.

Never ever had water in a carbon rim. My winter bike with FarSports wheels has been in serious rain. No drain holes and never water inside.

[Lelandjt]

...both 1/4 way around from the...

This implies just 2 holes.

And if I understand the description correctly, one on each side of the rim (drive side and non-drive side), and 180 degrees opposite each other. The locations chosen are 90 degrees from the valve hole.

Yup.
Getting the holes as close to the rim bed as possible helps water evacuation when the wheel is spun. Don't want to drill into that cross member though so if in doubt, go closer to the spokes.

[Butcher]

I would grind the hole, then a dab of epoxy.

[bobones]

Never ever had water in a carbon rim. My winter bike with FarSports wheels has been in serious rain. No drain holes and never water inside.

I get significant water ingress with my 3T Discus wheels, which makes quite a racket when frozen!

Apparently, water gets in through the spoke holes because nipple washers have been used in the build, which makes the interface between rim and nipple less watertight.

I've contemplated rebuilding without washers, but that might weaken the wheel and was advised against by the original wheel builder. Perhaps drilling holes will be a solution for me.

[Lelandjt]

Never ever had water in a carbon rim. My winter bike with FarSports wheels has been in serious rain. No drain holes and never water inside.

I get significant water ingress with my 3T Discus wheels, which makes quite a racket when frozen!

Apparently, water gets in through the spoke holes because nipple washers have been used in the build, which makes the interface between rim and nipple less watertight.

I've contemplated rebuilding without washers, but that might weaken the wheel and was advised against by the original wheel builder. Perhaps drilling holes will be a solution for me.

None of my wheels use nipple washers and I have several that would get water in them during bike washes.