• Charles Lindsey

Annual Bicycle Maintenance – Bottom Bracket Lubrication

This is the beginning of the season for many cyclists as Daylight Savings Time is about to begin and the temperatures stay warm. I wanted to inspect and lubricate my bottom bracket bearings. Bottom brackets, headsets and freewheel hubs are hidden within the bike frame and rear wheel hub. Therefore, they are easy to neglect. Unless something goes wrong. So, it is always a good thing to inspect these areas on an annual basis or have the LBS inspect them as a part of a yearly overhaul.

I removed my SRAM crankset first. The non-drive SRAM Red crank arm is a self-extracting crank arm. I took an 8-mm hex wrench and turn it counter-clockwise to remove the crank arm. The larger, more visible hex nut is the retaining ring. While it looks like the hex nut to remove, leave it alone, the smaller 8-mm hex nut presses against this retaining ring to pull the crank arm off the crank. But it is tempting. The 8-mm hex wrench will turn the inner hex nut behind the retaining ring. Once the crank arm is removed, I pulled the chain off the chainring. I could then pull the other crank arm away from the frame.

I could see the Enduro ceramic bearings in the bottom bracket covered in dark gray lubricant. I turned the inner ring of the bearing to see if the bearing moved smoothly without any embedded grit or mechanical problem. They turned smoothly, so I was relieved. If there any problems turning the bearings would have forced me to buy new bearings for about $140 for the pair.

I removed the bearings with the Park Tool bearing removal tool which I bought for the task. I could not find it at any of the LBS. It was $40 on Amazon. The tool came with bottom bracket bearing installation bushing that I was going to use a little later.

One problem that cropped up was the Trek bottom bracket sleeve that my Madone uses instead of the SRAM GXP sleeve. It was probably the original sleeve, and it snapped. Fortunately, the local Trek shop gave me a new one from a box of extras that they had. It is a Trek design quirk to use their own proprietary plastic sleeve to house the bearings and have the crank pass through the frame apart from the carbon fiber interior.

I cleaned the bearings with a degreaser, first with a standard bike degreaser and then with a more powerful kitchen degreaser, Goo-Gone. I rinsed the degreaser out with plenty of water and let them both dry. Both bearings were spinning easily in my fingers then. I lubed them up with Phil Wood Waterproof Grease.

I put together my own installation tool to reinstall the bearings. The Park Tool Press Fit Bottom Bracket Bearing Tool Set was $210 and handle multiple types of bottom brackets. Since I am not a bike shop and I would be doing this only once a year I had no need for this. I bought a ½ inch threaded rod about 6 inches long, two ½ inch washers and two ½ wing nuts.

I installed the Trek bottom sleeve into the bottom bracket. Then I put in the drive-side bearing in first, by lubing the bearing and the surface of the bottom bracket and passed the thread through to the other side and put the washer and wing nut on. Then I turned the wing nut until the bearing was firmly seated in the bracket. Then I did the same for the reverse side. Then I installed the crank and reinstalled the non-drive crank arm. I had to make a minor adjustment to the front derailleur since the alignment of the chainring was a little different from before. All in all, it was not difficult (I still rank installing and adjusting the SRAM Red front derailleur at the top of my annoyance list). On my first ride after the service, pedaling felt a little easier and smoother, so it was well worth it.

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