Hi, I'm doing a build and had the frame prepped. All ready to go for install of parts.

I pulled my 'stash' of bb assemblies. The first I picked looked great. Record cups with the rifled threads. Races are 100%. Pulled the ball bearings and noted they were 3/16" and obviously smaller than the usual 1/4".

Is this right? Does it really matter? The cups are great, they screw onto the shell perfectly and the spindle is super. I suppose the smaller bearing will allow for one more ball. That's a good thing.

Are these smaller bb used only for specialized purposes (eg track sets) or is it OK to use 'em for road cranksets?

If the spindle wasn't designed for the smaller bb, then it'd put the spindle a little to the right (all of 1/32".)

If the spindle was designed for the smaller bb, then all should be good. If it wasn't then it may affect the right side positioning of the spindle and the crankset.

Any insight as to the use of the Campy smaller 3/16" bb?

Steve

Maybe the application would help: Raleigh Competion GS, approx. 1978, Reynolds 531 db. I'm using a Centaur Crankset, requires a 111mm symmetrical bb. The bb spindle I'm using is 111mm. Steve

Campagnolo used 3/16" ball bearings in their bottom brackets 3 times.
Once in the early 60's, the outside of the cups will be stamped 3/16 but this is before the reverse internal rifle in the cups.

Next was with Super Record. The cups were alloy with pressed in races. They have the internal rifling. Mated up with the ti spindles of two different designs, initially hollow and later solid with threaded ends. two basic lengths, 113 and 115 mm.

Last was Corsa Record, cups the same as Super Record but the spindle was steel. Spindle lengths were short to mate with the C Record crank arm design.

Not sure what you have, but there is not a great deal of acceptable cross-era crank arm compatibility. I suggest you use it with what it was designed to work with, or sell it off, trade it off and get what you need.

Perhaps just invest in the 1/4" balls?
Worth a "test-assemble."

Yeah, what the heck. The spindle is good for my application. The cups are fine. The ball bearings may be wrong, but if so, maybe not by a whole lot. I'll try it. Should be fine. Steve

Placing ball bearings 25% lager than design intended is not a smart idea.

Mismatching 3/16" designed cups with a spindle designed for 1/4" is also not a sound idea.

It's just a fact that Campy designed some cup/cone BBs for 3/16 rather than 1/4. The best solution over all is to find out what crankset you have and research what BBs will work with it. Then see how you can handle it based on parts on hand, affordability, et cetera. If you just picked two random cups and a random spindle out of your BB Box, you don't even know if the three are a match.

Main effect of larger or smaller balls is that the wear tracks won't be where they were designed to be. I think it takes a lot of experience to know exactly what the resulting problems could be. If the spindle length and offset are correct for the crank and BB shell, and the "thin/thick" thing is correct for the cups, you can choose the balls you have, test assemble it, and see if the adjustable cup sits too far in or too far out. Adjust the ball size accordingly. Campy cup cone BBs when installed correctly have no visible threads on the non-drive side, and the lockring is fully threaded onto the adjustable cup.

You could look for a bike shop with a lot of old parts and old employees, with '60s Italian racing bikes on the wall with tubulars on the wheels. If you can find the guy who can service oll of them and restore actual classic race bikes, take your bike there and leave it with them.

Centaur crankset had a 111 bb designed for it, which was a cartridge BB. You can look on the website "www.bicycleclassics.com" to see if any of the spindles that are compatible with rifled cups are 111 mm. I suspect they are not that short. There's another site that has info on the full range of Campy spindles, but I don't recall what it is.

The Centaur BB and the very similar (dimensionallly identical) Veloce BB are (I think) still available, at least on Ebay, and they are a lot cheaper than hunting for used matched cups and spindles. Besides, the cartridges are the correct BB for that crank.

That crank is much less C&V than your Raleigh frame, if that matters to you.

Thank all for your advice and insight. It was extreeeemly helpful. I identified the bottom bracket assembly as a C Record one. It is 111mm length, symmetrical and the ball bearings are 3/16. The cups are alloy with the pressed-in races. It is a complete unit of C Record goodness!!! The length of the spindle is exactly what the Centuar crankset requires -- 111mm. So, I went ahead with it. After install I screwed the Centuar crankset onto cleaned spindle ends. Amazing. It went on very nicely. The chainline from the mid point of the seat tube to the mid point between the rings is 42.5mm. I'm kinda amazed it came out so well as that is what it is supposed to be!! The only questionable issue would be the compatability of the square taper used on the spindle and the square taper 'holes' in the crankset. As I understand, there were changes at different points as to the type of taper used. ISO, Campy and JIS. At this point, I'm more than satisfied and will keep smiling at how well it all worked out. Thanks again. Steve

As far as throwing a non 'C&V' part at the build-up, that isn't of much import to me. As long as it looks cool and works well (looking cool being of top concern), I'm happy. It'll work just fine too. Not a bad thing. It may not be mid to late '70s fine, but fine none-the-less. Steve

There is likely a minor mismatch between the C-Record spindle (Campy ST) and the Centaur (ISO), however any difference is moot as it works. The Campy spindle was between ISO and JIS, but closer to JIS (there is no real compatibility issue, just a difference of how far the crank will fit up or down the spindle before it stops); the change to ISO occurred in 1994. That being said, the Centaur crank will probably mount about 2mm more outboard that an earlier crank, which seems to be a good for your setup. Otherwise the current Veloce and Centaur cartridge BB are made for the Centaur crank.