Mudguard eyelet bolts - imperial thread size

[wafter]

To be fair, a single bolt that fits the threaded hole will not protrude inboard of the frame and present potential clearance issues like a nut would.

Plus you have the potential for the undersize bolt to damage the threads in the frame should the nut work loose, also if you're as OCD as me the potential for tightening the nut to damage the paint on the other side of the frame.

No-brainer just to source the correct fixing IMO; providing the correct spec can be identified and sourced.

 

[rogerzilla]

I usually tap them to M5. If an M5 bolt is a little too large for the existing thread, the thread could be 2BA, a very common traditional size. Pitch is the same but diameter is 0.3mm less.

An old post by Chris Juden on the CTC forum suggested these threads are usually 3/16" British Standard Cycle.

 

[mjr]

To be fair, a single bolt that fits the threaded hole will not protrude inboard of the frame and present potential clearance issues like a nut would.

Put the flatter head on the inboard and the nut on the outside. Then as well as fewer clearance issues, you can torque it to security without worrying about stripping the threads on the frame and finish off by protecting the inner head from corrosion a bit by coating with grease.

 

[Gunk]

These turned up today, 10-32 UNF fits into the original imperial threads and the 1/2" length fits perfectly, I ordered 3/4' for the rear to accommodate a rack but they're too long, 1/2" is the perfect length. Hope this helps anyone looking for a solution to same problem.

 

[Drago]

My Claud is M5.

 

[Gunk]

Did they switch to metric?