Not strictly a frame building question* but you guys always seem to know stuff no-one else does!
I’ve got an eye on a 2012 Cervelo R5 frame with a cracked mech hanger, but it has no fork. These use a random 1.125"-1.375" tapered steerer with an IS49/37(36deg) lower headset, and I can’t find a fork to fit it anywhere.
Firstly, anyone know of an aftermarket fork with a 37mm integrated crown race? Could be 36 or 45 deg as there are bearing options for both. Or a 1.375" steerer with a press-on race? Obviously the frame is for rim brakes and fast road geometry, but I would be open to ideas for a disc option and maybe a bit more tyre clearance*.
Secondly, are there any headset options to fit a 1.125" or 1.25" steerer into a 37mm ID/36 deg bearing? Seems that a press-on crown race with the right dimensions would do the trick (which I could get made if necessary), but I’d like the fork to match the headtube diameter like it should (1.125" may be too small, 1.25" should be ok as the nominal OD is only 2mm smaller than 1.375").
*I am considering modifying the frame to add discs and/or give it more tyre clearance, only since it’s a bargain and needs work anyway. That was my reason for searching ebay for damaged frames in the first place. Changing fork geometry would require a little research to make sure it won’t become a nightmare to ride. Or I might just have mullet brakes. Or make it a track bike. Who knows? If I can’t find a fork then it’s all moot.