A New (Old) Crank

2022-01-02T09:08

I'm very much not into parties. This year, I spent New Years Eve in my shed changing the crank and bottom bracket on the Holland.

Original Crank

I don't think that the old crank had been on the bike for too long. The cotters came out easily and there was still a little oil in there. The bottom bracket also came out far nicer than it should have. Usually the right-hand side of the bracket is really tight. I'm not sure if they're normally assembled with Loctite, or similar. All I know is that I often struggle to get them apart. It wasn't an issue at all this time. Since I don't have a 1¼" spanner, I use my drill press vice to hold on while I turn it¹. To take out the left-hand side, a hook spanner is needed to get the lock ring off. You also need a special spanner with two pins. They might be called a bottom bracket pin spanner but I don't know if that's the correct name².

Remove Crank

Bottom Bracket (RHS)

Bottom Bracket (LHS)

Removing Lockring

Once I got it apart, I found more Japanese parts and fresh grease. I don't think there was anything original on the frame at all. The rims and hubs are also Japanese.

I put it back together using a with a Bayliss-Wiley³ bottom bracket and a Williams Crank — both from the 50s. It also received new ball bearings and grease, of course. The old ball bearings were probably fine, but they're so cheap (and easy to lose when disassembled) that I use new ones just as a matter of practice.

Changing the bottom bracket isn't something I've done too many times. I got confused by the bike being upside down and accidentally installed it backwards, but it was easily fixed.

Replacement Bottom Bracket (RHS)

Replacement Bottom Bracket (LHS)

Next, I needed to install the crank. I'm using vintage parts so the crank arms are held onto the bottom bracket with cotter pins rather than a bolt like more modern bikes have. My bikesmith cotter press⁴ would only work for one crank arm. There wasn't the room on the chainring side, so I resorted to an old-fashioned hammer. To prevent damaging the bottom bracket, I supported the underside of the crank with a lump of Native Cherry (Exocarpos Cupressiformis⁵) to transfer the energy of the blow that I was about to deliver down to the floor instead of through the bracket I just replaced. I gave the back of the cotter a few light taps to align the crank arm, shaft and cotter-flat all into the rightful places, and then I beat it into place with three of four good strikes.

Then, I put the pedals onto the new cranks.

All Together

On the Floor

I took it for a ride this morning and it worked great. If the cotter pins aren't seated properly, the crank arms can move. If that happens, the soft metal of the cotters give way allowing more movement. Apart from feeling terrible, sloppy crank arms quickly destroy the cotter pins. Once that happens, no amount of beating will get the crank arm tight. Perhaps you can file the cotter flat but I haven't tried it. But for me, the cotters were tight. When I got home from my ride I tried to drive the cotters in further, but they wouldn't move so I'm confident that they're in to stay.

I also noticed that the rear hub is in pretty bad shape. I won't do anything about that for now. I eventually want to build some 700c wheels with a vintage coaster hub in the back. I have a Campagnolo Record hub that I will probably use for the front. It's Italian rather than English but its a good hub so I will use it. I might even try and find another one for the back.

1. Dawn Drill Press Vice

2. Bottom Bracket Pin Spanner

3. Bayliss-Wiley

4. Bikesmith Cotter Press

5. Native Cherry

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