xenologer

A question about replacing cones in a hub.
I notice that some cones have differently sloped surfaces. ie shallow vs steep curves for the bearing track
How critical is it that a replacement cone match this?
Would it be acceptable to interchange differently shaped cones; would the bearings simply ride is a slightly higher/lower circle in the cups? with a corresponding adjustment needed to the axel spacers to account for how deep the cones sink in....

given a 'naked' hub, how would you even tell which cone shape it needs? if it even matters...?

Thanks

FBinNY 

There is some latitude in cone shape, and anything reasonably close will work as far as the bearing is concerned. But there may be issues in with mis-matched diameters between the cone and dustcap.

A decent rule of thumb if you can't get an exact replacement is that if it looks like it'll work, it will.

MichaelW

They are self centering so the shape is not critical.
They do come in different threads, widths and depths.
Most of my older Shimano hubs have had to loose their rubber seals due to mis-matching replacement cones.

mrrabbit 

As long as the bearings sizes and count are the same - should be okay.

However, some cones have the nose cut off short - some cut long. Just make sure the bearings track a few millimeters in from the nose or tops and are clearly running inside the curve.

You will need some spacers and locknuts lying around that differ a millimeter or two from the original to adjust for the "out of spec" cones. I.e., you want to make sure your final drive side "center-of-flange to outside of drive-side locknut" spec stays in spec while the overall axle spacing stays close to original. Use the non-drive side as your "buffer" for finishing up the overall axle spacing.


=8-)

xenologer

Thanks for advising.
in this particular instance, I've opted to wait and try finding the correct cone.
The available (mismatch) substitute I had on hand was larger diameter even at its narrowest point than the bearing track circle on the old cone. So, outside the range of wiggle room I figure.

Think riding around on pitted cones till I can get new cones will damage the new ball bearings I just put in? doh! I probably should have just kept the old bb's... but somehow it doesn't seem right to reassemble without at least *some* form of improvement...

Kimmo 

The pits almost certainly didn't end up where they were created, when you put the cones and wheel back in, so you should be right for a while unless you've got too much preload.

vredstein

There are a few factors you need to know to find an exact cone match including, the small-end diameter, race curve, large end diameter, and overall length. There are ways to make up for differing curves by possibly using different sized balls. To get some idea of where the balls are riding on a cone, you'd fill the hub cup with the proper number of greased balls. Only grease the balls enough to give a very light coating. Make sure the test cone has NO GREASE on race surface. Lower the cone down onto the balls squarely, and pull straight out. Now look at the grease prints on the cone and where they end.