Tuesday, August 08, 2006
REMOVING THE ONE PIECE CRANK FROM THE FRAME
Most coaster brake bikes are equiped with what is called a one piece crank bottom bracket. They can also be found on BMX bikes and the cheap variety chain store bikes. This set-up is pretty heavy compared to the three piece bottom bracket, but it has the advantage of being pretty tough with its washing machine type crown bearings. I've opened up bikes that the bearings had never seen the light of day for 30 years and still find them in working order. Also, I've never seen a one piece crank break or come off.
Our Lowrider project is equiped with such a bottom bracket and we are going to take it off. Pretty easy if you follow my step by step illustrations. One thing to remember is that some threads are reversed on a bike, like the left side pedal and the locknut and bearing cone on the left side of the bottom bracket. You have to unscrew those by going clockwise.
After you've taken everything apart, make sure you store it all in a place you can find it again and not lose anything throughout the cleaning process before reassembly. Our next article will be about how to clean out all these nice parts. Until then, ride safe.