Raleigh Sports Bottom Bracket Servicing


Friday featured some good weather once some storms passed, so I got back to work on the Raleigh Sports. The task for the day was to check, measure, and sort the ball bearings for the bottom bracket.

















I had been soaking about 30 or so ball bearings of the appropriate nominal size in WD40 for about 2 days. I put them on a small tray and began to sort them into two cups: good and questionable. A smooth bottom bracket comes from having good lubrication, good adjustment, and good quality bearings and race surfaces.







The bearing size for the Raleigh Sports bottom bracket is .25 (quarter inch). I pulled out my calipers to check each of the bearings for size. Bearings at or extremely close to .250 were kept, those varying in size were put in the questionable cup. Those with pitting also went to the questionable cup.








I also took the time to clean up the bottom bracket parts and race surfaces. I want them shiny and smooth, ready to receive new grease.




















When working on a Raleigh bottom bracket, I tend to think the best way is to leave the fixed cup in place if at all possible, and then work from there. You can use the small, soft metal brush to clean the fixed cup. Do not use hard steel brushes or anything that will scratch the fixed cup race (or any other race for that matter).  I used a small wire brush of soft metal (brass) and some WD40 to clean the old grease out of the frame bottom bracket and the fixed cup. 












Here are a few shots of the progress. The bicycle is up on its wheels and slowly coming together.

I will add that it is important that you remove all old grease or oil from the insides of the crank holes, where they contact the bottom bracket spindle. I used Formula 409 to clean the insides of the crank holes and the spindle itself. It is a common misconception that you want to grease the contact points between the spindle and cranks. You actually want more friction between the cranks and the spindle. You grease the face of the cotter pin not the contact point between the crank arm itself and the spindle.
 Again, you want these parts clean. Every bit of old grease you get off will add to the smoothness of the final drive train. Remember, no grease in the crank arm spindle holes. 
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