This is the time I stressed about when thinking of rejuving the old Trek. Years ago I had updated the drivetrain with a new Sugino compact crank and seven speed freewheel. I knew that the BB axle was a couple mm long for the crank but didn't really worry about it. Now the bottom bracket is shot. I know these old clipped bearing units are supposed to last forever, but things don't always stay nice. Last year I had to replace the bearings, they literally fell out of the clips when I tried to lube it. This year, I can't keep it in adjustment no matter how I try, it just creeps tighter and needs readjustment each time I ride. So, replacing it with a new cartridge unit is all that makes sense.
When I took it apart the retaining ring and adjustable cup stuck together until I had the unit apart. The axle and bearings came out normally except that one of the bearing clips was broken and in pieces. Oops!
That's part of the problem. What I wasn't looking forward to was removing the the fixed, or drive side, cup. It had never been removed and I anticipated it would be stuck since that is the common wisdom. I consulted Sheldon Brown and found that he had developed a reasonable and inexpensive method for removal. It amounts to placing a bolt through the axle hole with washers on each side and a nut to tighten.
The theory is that, since the cup has reverse threads, when you tighten the nut it will automatically loosen the cup as you tighten the nut. I was prepared for a battle and expecting failure and the use of "Freeze Off" or some other extreme measure.
I inserted the bolt, put the nut and washer in place and used a long socket to hold it
while I tightened the nut. To my surprise, it worked! The first time, without effort, muss or fuss, it just came right out! Thank's again to Sheldon Brown and his encyclopedia of bikology.
Now I am ready to take the frame off to a powdercoater since I won't need it for a couple of weeks.
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