Friday, June 13, 2014

Fighting with a bottom bracket

I've always been a "Know enough to be dangerous" kind of person. I have always been willing to jump into a situation without completely knowing what the heck it is that I'm doing. Sometimes that makes me look like a total badass...most of the time it makes me look like a total jackass.
The green bike I posted about earlier had a cottered crank, I wanted to replace the double crank with a slick Shimano triple I picked up. If you've never had to deal with one, consider yourself lucky. Some older bikes used wedged shaped fasteners called "cotters" to hold the cranks on the bottom bracket axle. They have a nut to hold them in place and they have to be driven or pressed in. If they've been in there for a while they are a real pain to get out.
The cottered crank on my Raleigh twenty
 The non drive side came out fine, "Super easy" I thought to myself. "I'll have this thing off and ready to climb steep hills with my triple in no time" The bicycle gods had a different idea of course. I worked on the drive side and the thing wouldn't budge. I used oil, penetrating oil, WD-40...I'd use WD-50 if they made it. I tried to get it out with a punch and hammer, I tried drilling it, I tried every trick in the book (except taking it to an old bike shop and having them use a cotter press, a tool used for just this purpose) I tried cutting it with my dremel...that was a waste of time. I finally had to take it to my bench grinder and grind and grind until it fell apart. 
Well, there was no going back now, the crank was trashed but at least I could get to that non adjustable cup. I tried to get it off with my wrench but it wouldn't budge. I took it to my favorite bike shop and they couldn't move it either. I took it to another bike shop and they decided to try it the other direction and it twisted right off. 
What we seemed to have there was a Swiss bottom bracket. What does that mean? It means that although it's threaded like a French BB at 25.4 TPI the fixed cup is threaded opposite of  the French by being threaded left handed. In other words I'm kinda screwed.
I later found there were other solutions. I could a) keep the cups (i was able to save them) and find an Japanese made square taper spindle that was intended for Italian bikes...still with me? I found one or two of them but I couldn't find the right size. b) purchase a new bb cartridge from Phil Wood for like $200 (ain't happening) or c) I can get threadless bottom bracket from VO (still a little pricey) or Sunlite ( cheap...now you're talkin). Why the price difference? because you always get what you pay for.
So I stripped the frame of all the components because by this time I got my Schwinn Continental (more on that bike in another post). I rattle canned the frame a nice dark green and was about to rebuild it yet again as as a single speed or possibly a fixie when we decided to sell our house. My whole summer was spent cleaning, throwing stuff out and getting things fixed that needed fixing for the past 10 years. There was no time for bike building or riding. All our work paid off because we sold the house in 3 days.
Once we got settled in I was able to start tinkering again. The new house left us a little cash poor for a bit so buying a flip flop wheel was out of the question. If I was going to rebuild this bike, I would have to do it with parts I had it laying around. Fortunately,  I had a lot of spare parts. I had a 26 inch wheel set - 3 speed coaster brake- so I was good there....sort of. The old green bike was intended for 27 inch wheels, that inch makes a difference. I needed short cranks, the shortest I could find was 152mm. If I spent a little more time I could have found a crankset with a slightly larger chain ring (this one only had 32 teeth) but I didn't want to spend a lot of money and this was super cheap. Remember when I said you get what you pay for? 

It couldn't be more true. I don't know if it was the cheap BB or the cheap crank but the non drive side crank would always come loose. I guess something was stripped or the crank didn't quite fit on the taper. Either way having to tighten it every few miles got old quick. It was a fun ride while it lasted though.

I kept the wheels and saddle but everything got donated to B-Works St. Louis thus ending my affair with this old green unspectacular 70's road bike. I think I learned more about wrenching a bike with this thing than any other bicycle. For that Mr Kalkhoff I thank you - whoever you are.
Thanks for reading. Until next time, keep your spanners where you can find them!

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