Shimano freewheel-freehub conversion
 

I'm considering upgrading my mid-80s road bike from freewheel to freehub, as I discovered today that my rear axle is slightly bent at the right-hand bearing. It has a 7-speed indexed downtube shifter, and the indexing works fine with a modern Shimano Hyperglide freewheel. My question is this: Will a 7-speed Shimano cassette be compatible with the indexing, given that the current freewheel is? I'm rebuilding the rear wheel anyway, for various reasons, so this seems as good a time as any to convert.

Thanks in advance

Yes. The spacing for indexing is the same.

You need a new wheel or hub for the converting. other than that yes the spacing is the same and it will work.

SRAM and Shimano use the same spacing, so that expands your options. Do they still make the freewheel-to-freehub adaptors? Haven't seen one in years. FWIW, you don't need a new wheel, or even a new hub. You just need a new axle. Might think about new bearings as long as you're in there.

He's putting a new hub in, ostensibly for the increased strength a freehub style hub gives. So the issue is moot. His original question is ask and answered.

A lot of heavier guys get plenty of use out of freewheel hubs.

According to Jobst Brandt, freewheel axles bend and fail because of metal fatigue, so they'll be good for a while, then they'll go bad.

Replace every year or so and it will be as good as a freehub unless you hit a lot of bumps or are very heavy or powerful.

I personally believe that it is utterly critical to keep the cones adjusted to zero slack but have not found any corroboration from anyone in the know that a poor adjustment can cause bending.

And Jobst Brandt established his baseline references for bicycling riding a road bike with a 6-speed freewheel.

Besides, fatigue appearing as residual deformation? That has to be very close to the moment of breakage.

You should reread what he wrote.

He does not say that. It's primarily due to the inherent design of the freewheel hub that causes problems (exception - phil wood and others). Replacing the axle every year isn't going to prevent you from bending it going off a curb with a heavy rider.

http://www.sheldonbrown.com/brandt/free-k7.html

I stopped breaking Campag freewheel hub axles, when I bought some 'wheels of Boulder' axles,
the temper that Campag uses is hard to the brittle end of the spectrum , rather than being a little ductile, I surmise .

but my Touring rigs have had Phil and Bullseye freewheel hubs ..

He doen't exempt the Phils or any other.

About Jobst Brandt, I only wanted to say that he said freewheel axles typically fail in fatigue.

I agree that the design is weaker than a freehub, but you really shouldn't hop curbs on a road bike anyway. The higher stresses placed upon the axle also cause it to fatigue sooner than it otherwise would as well as making it more susceptible to damage.

However, provided you are a bit more careful than you'd have to be with a modern bike, it should work fine until it fatigues.

The fact that fatigue causes the failure does mean that if you simply replace the axle, it will be good until it fatigues again.