Benotto Project Update – Cold-setting a frame
It turns out that the Benotto frame I got second hand off eBay, had most probably been used as a single-speed or fixed-gear, because the rear dropout spacing was down to 122 mm. It is supposed to be 126 mm and I would have to cold set it to 130 mm if I wanted to use a modern groupset and wheels.
So, cold setting it from 122 to 130 mm is a bit much. Do-able but it will take longer. At least longer than I expected. My solution was to use a threaded rod and a few washers and nuts. I put two washers and one nut on the inner side of each dropout. On one of the dropouts (right), I put a washer and a nut. This way I clamped the rod on the right dropout.
Then I started turning the left nut so it would push the left dropout towards the left and therefore spread the dropouts. I decided to spread them over the 130 mm that I need. I stopped when I couldn’t spread the dropouts further by hand. Finally, I added another washer and nut on the outside of the left dropout in order to make sure that the rod will not slip or get pushed and damage the dropouts. I will have to leave for a few days and see what happens.
UPDATE: I decided to speed up the process. So I turned the nut to spread the dropouts further. Then back to normal (no tensions at all) and measured. It needed spreading more and then measured again. Until I reached the 130 mm that I wanted. I suggest you do it bit by bit (5 mm increments) and be very careful. Some people say you should clamp the brake bridge to prevent the seat-stays from snapping. I think that a frame is too strong for that.