Moby headset bearings

I'm in the process of cleaning up / overhauling a new-to-me '77 Moby 50V. It's generally in quite good condition save for a few dings and scratches, and is pretty unmolested; nobody seems to have put a single wrench to it in 42 years.

I pulled the forks and headset off, being careful not to lose any bearing balls, as there are a bunch of them and they're not caged.

After cleaning them up, I counted a total of 46 balls --- presumably 23 for the upper and 23 for the lower.

BUT .......

1) Rebel Moby says there should be 25 in the each, for a total of 50 balls.

2) The Moby repair manual says there should be 26 in each, or 52 total. (EDIT: The Moby parts manual agrees with the repair manual, though that shouldn't be a surprise.)

p. 65:

3) The Treats replacement has caged bearings. I could buy that, but my races are in good shape, so I don't really want to replace the whole setup. Also---and it probably doesn't matter here---more bearing balls is stronger, stiffer, and smoother than fewer bearing balls.

Anyone have a definitive answer as to how many there should be in each of the bearings? 23? 25? 26? Something else? I'm leaning towards putting 26 in there.

Side note: They measure to 5/32" diameter. I'm sure I can pick up extras at any hardware store, but I just don't know how many to put in there. And before I get any "just try 23, 25, and 26, and see which fits best" comments, it's really hard to tell what the 'correct' number is based on feel; much harder than, say, with a wheel bearing which only has about 12 or whatever larger diameter balls. (edited)


Re: Moby headset bearings

Nobody said it was easy .

Try as many as will fit .

A little space between will make no difference .

Re: Moby headset bearings

caged bearings are definitely easier. 25 will work almost exactly as well as 26.

you can miss a few.

Re: Moby headset bearings

Early serie 50 had 50, same as the AV56-59, later had 52, if you have a 51 then it is a caged bearing.

Uncaged You need 50 or 52 each 3,96mm for the forks - 25 or 26 top 25 or 26 bottom. You could also use 5/32 inch if you can not find 3,96mm it is basically same-same.

Re: Moby headset bearings

Nice, thanks all.

I put 26 in each, and made up the difference with 5/32-dia. balls from the hardware store.

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