Seems like a vent hole would be on the bottom? Picture is from an ad for a different bike, so I know at least that it came from the factory like that.
by LittleKillshot
Seems like a vent hole would be on the bottom? Picture is from an ad for a different bike, so I know at least that it came from the factory like that.
by LittleKillshot
6 Comments
They used to hold the brake cable housing guides.
Those are holes for cable housing guides. The guides were plastic and prone to breaking.
https://www.ebay.com/itm/394968924984?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=G-aZ20-KTGS&sssrc=4429486&ssuid=p_4d-BibSWq&var=&widget_ver=artemis&media=COPY
Speed holes?
These holes were mounts for plastic cables housing guides, common on Cannondale models of this vintage. The guides snapped into these holes (similar to modern car trim clips) and were proprietary to Cannondale.
When they break off, you’re kinda left with no good options but zip-ties since (to my knowledge) they’re not available as “spare parts” for these frames.
If you wanted to go custom, you could probably 3d print plastic cables housing guides and epoxy or affix them with small metric bolts?
There are AliExpress cable guides that rivet onto the frame, I just don’t know if the hole spacing is the same. I think the AliExpress ones are further apart. In which case I’d find someone to 3d print some and then rivet them on for the cleanest look.
https://preview.redd.it/8ysybdv1l9ye1.jpeg?width=1079&format=pjpg&auto=webp&s=1eb5387737452f89c5022227e826983a5140c24c