Hi, I want to drill a drain hole in my bottom bracket, but I also want to have some sort of bung or cap for it to stop crap getting in. Any suggestions as to what I could use?

Blanking Grommets

(other sizes are available)

http://www.ebay.co.uk/itm/6-5mm-Blanking-Grommets-Blind-Closed-1-4-Inch-Electrical-Non-Rubber-Qty-20-/181564818649

Just drill the hole. Don’t worry about a bung. I’ve always drilled, never bunged and always been okay.

When i did my Orange 5 I drilled out 4.5mm and used a 5mm tap then you can use a disk bolt

Are you really going to remember to drain it every time you ride in the wet? Otherwise you’re probably better off just having an open hole.

Just drilled my 6 month old Cannondale Jekyll, as thats what killed the BB30 BB. Rust line along the bearings. Used a 5 mm drill bit and left open to drain.

Drilled all my frames and never bothered with a bung, never been a issue with them filling with crap compared to the amount of moisture that can get retained there when there is no drain hole.

Cheers guys – will just be leaving it open then!