# Wanted: Schwinn Twinn Crank Diagram



## Hydrostream1 (Mar 18, 2009)

I have a 1964 Schwinn Twinn single speed. I am looking for a  breakout diagram for reassembly of both the front and rear crank and sprockets. My chrome guy took from November to March to get my parts back, and I have long since forgotton how they go back together! Additionally, one crank is smaller in diameter then the other, and have different numbers. I'm not sure which is the front and rear. Any help would be apprecieated.


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## bikeaddict (Oct 13, 2011)

*Ok*

Lets see, Im assuming you have Asthabula cranks (one-piece), in which case, both cranks are different sizes, the one with the lesser amount of teeth goes in the front, the larger one with the two cogs goes in the rear bottom bracket.
install the chain for the front to the INNER ring in the back.  

Puttin together a one-piece setup is about the easiest kind to put together, but there is one thing you can do that will make you band your head against the wall for hours (my head still hurts)...

When either installing or removing the crank, Do NOT try to pull out the crank, or install it for that matter with the bearings already in their proper homes.  Install the crank by itself first, then put TONS of lube on/*in* the bearing/retainer piece and slide it over the arms and into the bb

As im sitting here writing away from the bike, i can remember if the bearings are installed inward or outward, but either way, you'll know if you but the retainer in right because even lightly tightened and heavily lubed between the cup and cone, you will hear a nice grinding noise, thats bad, flip it around and it should both 1) seat better and 2) no more grinding noise.....maybe someone else can help me out here.

So it goes the same for both bottom brackets..install in this order
1 crank
2 bearings packed in their retainers...facing outward? (all 4 are the same)
3 cone (the thing with the two areas that look like you want to hit em with flatheads to tighten them)
4 washer (they hava groove in them so you can screw this one up)
5 locknut

after you tighten the locknut, it becomes a balance between removing any play in the crank (wiggle it around),
and not getting it so tight that the crank doesn't spin freely.  I found that on my Twinn i had to go a little tighter than normal, but i def. didn't want it to wiggle in the bottom bracket, potentiall damaging the bearings or retainer.

one more thing, make sure that when you install the front chain, that both cranks/pedals are working in unison....one the same side...at the same time  This will avoide a nasty kick to the heel by the person in back seat.

Hope that helps
good luck


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