my name is Alex and I’m new here. I’m a bit of an amateur but I’ve decided to attempt the modernization of an old French Liberia racer from 1978. The aim is to create a bike I can use as a daily commuter bike.
The variable cup came off easily enough on the non-driver side. But the fixed cup on the driver side is not only really stuck, it also has a non-standard size! There are two flat edges for an open wrench/spanner with a 37 mm gap between the flats. Unfortunately, I do not own a 37 mm wrench, so I tried to loosen the cup using an adjustable wrench and failed miserably! The amount of torque needed was just too great and the wrench kept slipping off due to a combination of the unavoidable amount of ‘play’ in the adjustable wrench setting and the fact that the fixed cup is not very wide (about 2.5 mm I think), which certainly does not help.
One helpful post on stuck bottom-brackets suggested using a large vice to clamp the cup and the frame should then provide enough leverage. Also, it might be helpful to use some penetrating oil from the inside of the BB and to give it some time to seep into the threads. Right now, sadly I don’t have either of those in my toolkit, but I have a feeling this might change soon!
So, I’m thinking I might need to use a regular open-ended wrench of 37 mm width, but these seem to be impossible to purchase anywhere, given the non-standard size. I’m also thinking that, to avoid slippage, the wrench should ideally be kept in position while torque is exerted. Apparently, there is a device to help do this being sold by Park Tool, but it is not cheap and may be too soft for the task as it's made of aluminium, according to the reviews at least. I guess making some sort of home-made retainer using a couple of metal plates held in position using a threaded bolt / rod and two nuts might be the way to go – not sure yet.
So anyway, this task seems to be a bit of a tough one! Not sure if the bench vice option is preferable or if there are other solutions out there - ideas anyone? Any feedback you folks might have on how to best approach this would be highly appreciated.
Best Regards, Alex in Hamburg