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Parallel Chain Stays
#1
OK. I ride a Flying Pigeon . I live in China. For those not familiar with FPs, they are very similar to old Raleighs and have horizontal drop outs.

I just installed a 3 speed gear hub and there is drag on the pedals. Sturmey archer manual says that the cause of drag on the pedals is un-parallel chainstays.

It does take an amount of effort to squeeze the chainstay to the point where I could bolt up the hub axle. Of course that changes the angle

So here is the question:
1. How do I know I have unparallel chain stays?
2. Is parallel measured before or after reassembly?
3. If they are unparallel what do I do about it? This is the way the bike is made.
4. Is there any other possible cause for this dragging, like an over tight chain?
5. How would I loosen the chain?
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#2
A tight chain could be causing some problems. It should have a slight bit of slack to keep things rolling smoothly.
As for the parallel chainstays, a bad angle could be causing problems... would you be able to upload some photos of the bike and stays?

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#3
If you are having to compress the frame to tighten the wheel, you are definitely changing the alignment of the dropouts at the end of the chainstay. It sounds like the hub you bought is narrower than the original hub. Normally you would measure if they're parallel with the wheel out. But what really matters is if they are parallel when the wheel is in. They may look parallel when the bolts are tightened down, but they are probably still flexing the hub which is causing the problem.

If there is enough room on the axle, add some washers or spacers on each side just inside the frame so the frame doesn't have to be compressed to tighten down the wheel nuts. If the axle doesn't have room for that, you may need to bend the dropouts and frame a little so the frame doesn't have to flex so much and the dropouts are parallel once the wheel is installed. Obviously, this needs to be done carefully.

Flying Pigeons are a little finicky. You might try contacting Flying Pigeon LA at info[AT]flyingpigeon-la.com

He might have some advice.
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