A few weeks ago I bought an old Bioracer mountainbike. I wanted to use the Manitou Skareb Super fork that came with it on a Giant ATX550 frame, to be rattlecan-painted by me (thank you, ETOE, for your videos).
When I disassembled the bike I was very surprised to find the tubing decal say it is made from Columbus Genius tubing!
Proper examination revealed some potentially nice fillet brazing of the toptube and headtube assembly.
The bottom bracket cups were stuck, so I tried to get them loose with Rustyco and accelerent. The nondrive side cup went out nicely. The driveside cup not so much. Having tried everything, including heating, I decided to gently hacksaw it.
That worked out nicely. After trying to turn the remnant loose, which did not work, I squeezed the cup loose with waterpump pliers and pulled it out: it turned out that the bottom bracket has an Italian thread! I never made the connection 'Columbus' and 'Italian thread', also because the driveside cup wouldn't turn anti-clockwise. It never occurred to me to measure the diameter of the nondriveside cup nor the width of the bottom bracket...
Fortunately the driveside thread seems to remain in good order, although I still would have to check. Unfortunately the bottom tube has a ding approximately 7-8 cm's under the headtube.
I wonder what your thoughts are about the integrity of the frame, riding it with the ding?
Also, the width of the BB-UN72 axle that came with it, has length of 107,8 cm. Is that an odd size? It seems rather narrow to me.
The fork was a later/'02 upgrade. What rigid fork would you recommend for this '91-'93-ish frame?
I would be glad to hear your advice.
When I disassembled the bike I was very surprised to find the tubing decal say it is made from Columbus Genius tubing!
Proper examination revealed some potentially nice fillet brazing of the toptube and headtube assembly.
The bottom bracket cups were stuck, so I tried to get them loose with Rustyco and accelerent. The nondrive side cup went out nicely. The driveside cup not so much. Having tried everything, including heating, I decided to gently hacksaw it.
That worked out nicely. After trying to turn the remnant loose, which did not work, I squeezed the cup loose with waterpump pliers and pulled it out: it turned out that the bottom bracket has an Italian thread! I never made the connection 'Columbus' and 'Italian thread', also because the driveside cup wouldn't turn anti-clockwise. It never occurred to me to measure the diameter of the nondriveside cup nor the width of the bottom bracket...
Fortunately the driveside thread seems to remain in good order, although I still would have to check. Unfortunately the bottom tube has a ding approximately 7-8 cm's under the headtube.
I wonder what your thoughts are about the integrity of the frame, riding it with the ding?
Also, the width of the BB-UN72 axle that came with it, has length of 107,8 cm. Is that an odd size? It seems rather narrow to me.
The fork was a later/'02 upgrade. What rigid fork would you recommend for this '91-'93-ish frame?
I would be glad to hear your advice.
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