07-01-2012, 06:30 PM
The bike is an old Flandria with a Maeda Perfect FW on a Weco hub.
This bike had about 1/4" transverse peak-to-peak wobble in the freewheel (10-speed, "big" gear.) Everything about the wheel was so true, I figured it had to be cross threaded.
So I leaned about freewheels and removed it to find it cross threaded as expected.
I cleaned up the threads with a 24 pitch thread file and the FW spins on nicely. I don't think the threads were damaged that badly. After 1-2 thread engagement, the FW is nice and snug with no slop. I can turn it on by hand all the way. It is nice and smooth with Never Seize on the threads.
Now here is the question I need answered:
This bike had 2 thin, about 1/16" square cross-section, spacer rings stacked on the hub before the FW was installed. There was also a plastic chain guard with an ID that was nowhere close to fitting over these spacers.
These rings were badly distorted, one more than the other - the worst one is now unusable.
Further, the plastic disc chain guard ID was too small to fit over these spacers, so there was a nasty haphazard stack of the 2 spacer and the guard beneath the cock-eyed FW.
When the FW is tighened, should it bear against these spacers or a flange or should you simply bottom out the hub threads?
There is a very narrow flat on the hub that these spacers could thrust against, but one of them was already starting to roll off this flat.
Frankly, I can't see this hub flat being wide enough for any kind of spacer bearing.
If I put the FW on the hub all by itself, the threads will bottom out.
There is a definite flange on the FW that could bear nicely against spacer washers. However there is nothing like that on the hub.
There is over 1/16" clearance between the FW flange and the hub flat.
If the FW must seat on its flange, then I would think the best course of action would be to use a wider steel washer that would not "roll out of the way" or make a washer that fits outboard of the hub flat. This outboard spacer would bear against the hub flange right next to the flat. While not machined, it is probably true enough.
QUESTION: Do I need a thrust spacer installed for the FW to bear up against or should I just let the FW bottom out in the threads?
Thanks in advance,
Tom
PS. I already assume the plastic disc chain guard ID should be enlarged to fit on the spacer.
This bike had about 1/4" transverse peak-to-peak wobble in the freewheel (10-speed, "big" gear.) Everything about the wheel was so true, I figured it had to be cross threaded.
So I leaned about freewheels and removed it to find it cross threaded as expected.
I cleaned up the threads with a 24 pitch thread file and the FW spins on nicely. I don't think the threads were damaged that badly. After 1-2 thread engagement, the FW is nice and snug with no slop. I can turn it on by hand all the way. It is nice and smooth with Never Seize on the threads.
Now here is the question I need answered:
This bike had 2 thin, about 1/16" square cross-section, spacer rings stacked on the hub before the FW was installed. There was also a plastic chain guard with an ID that was nowhere close to fitting over these spacers.
These rings were badly distorted, one more than the other - the worst one is now unusable.
Further, the plastic disc chain guard ID was too small to fit over these spacers, so there was a nasty haphazard stack of the 2 spacer and the guard beneath the cock-eyed FW.
When the FW is tighened, should it bear against these spacers or a flange or should you simply bottom out the hub threads?
There is a very narrow flat on the hub that these spacers could thrust against, but one of them was already starting to roll off this flat.
Frankly, I can't see this hub flat being wide enough for any kind of spacer bearing.
If I put the FW on the hub all by itself, the threads will bottom out.
There is a definite flange on the FW that could bear nicely against spacer washers. However there is nothing like that on the hub.
There is over 1/16" clearance between the FW flange and the hub flat.
If the FW must seat on its flange, then I would think the best course of action would be to use a wider steel washer that would not "roll out of the way" or make a washer that fits outboard of the hub flat. This outboard spacer would bear against the hub flange right next to the flat. While not machined, it is probably true enough.
QUESTION: Do I need a thrust spacer installed for the FW to bear up against or should I just let the FW bottom out in the threads?
Thanks in advance,
Tom
PS. I already assume the plastic disc chain guard ID should be enlarged to fit on the spacer.