Hey all, I've got a weird frame in the shop, seems to be a vintage tig welded road frame with a threadless bb. The shell is 68mm and was built intentionally with no threads. THe bb I pulled out used skf explorer bearing, size 6003, retained around an axle with a pair of c-clips. THe guy who brought it in wnats to use it as a fixed gear but has been having problems with the c-clips popping out, any idea if this will work or should we just thread the bb shell?

Are you sure it's tig welded? Maybe it's a fillet brazed Viscount? What's the fork (if any)?

My guess is a Viscount, but I think some early Klein frames (which would be tig welded aluminum) also used this type of BB. Would something like this https://www.velo-orange.com/grcruthbobr.html work?

Teledyne?

I would agree with Viscount and this VO BB too. threading a BB is a huge undertaking and labor charges can well exceed the cost of this great BB provided it fits in the shell.

There are also cartridge BB from Edco and Mavic that would work too.

Pretty sure my Teledyne has a threaded bb. I'm using the VO threadless on my Swiss threaded Peugeot and it is working great.

You can also go with a Mavic BB that uses tapered lockrings rings (they seem to be plentiful at eBay), but you will need to find access to a Mavic BB shell face tapering tool.
I think VO copied the Mavic BB with their version. Patents on it might have already expired.
It was a good idea, but seems to have been "Betamaxed" into oblivion as threaded BB users never really saw the need to switch over to their system.

Chombi

No, unlike the Mavic BB, the VO cartridge does not require any chamfering of the BB shell prior to installation. The Mavic BBs are nice, but be certain you have access to the chamfering tool before you buy one.

Stronglight also made a threadless bottom bracket, far rarer than. although a bit of a rip off the mavic system.

I think I've seen those too.....would the Mavic BB facing tool work for the Stronglight version?? Was the Stronglight version part of their Delta group?
I've considered going to the Mavic and Stronglight BBs I've seen for sale for my French bikes (specially on my Swiss threaded 84 PSV), but like most, I feel reluctant to irreversably modify the BB faces on my bikes, although many had stated that the existing threads should still work after the Mavic BB shell facing change if they are properly cleaned up. Could go with the VO, but I really want to keep the totally French "theme" on my bikes.
Anyone ever use a conventional threaded BB on a Mavic tool faced BB shell yet??

Chombi

I bought a frame that had been faced for a mavic BB and installed external cups for campy cranks. Works fine, although I am using a BB that effectively cannot loosen over time.

And I believe the mavic tool will chamfer properly for the stronglight BB (but it was not for the delta set)

The Stronglight cartridge BB pre-dates Mavic's by several years.

I can't find any specific literature to date the stronglight model but if it does predate 1982 I would be surprised.

If you end up having to thread a BB shell with 1.370X24 BSA (standard euro) you will need a shell inside diameter of 1.325"-1.335". to begin with. If yours is smaller, you can use a 1-1/8" (OS) deep head tube reaming cutter to achieve a usable diameter.


I have a Teledyne in my shop to fix some cracks. It's standard BSA threading.

I'm told the Viscount BB can be threaded to Itilian size but not british.
And FYI. BSA made a sleved BB in the 30s--they were used on CCM bikes amoung others.

Hey all, sorry for taking so long to reply. The kid came back and yes, it is a viscount. Someone welded track ends into the frame and removed the decals. Any idea on how to re-instal the bb/if this setup is "safe" for fixed gear riding?

how safe it is to ride just depends on the qualit of the welding. reinstalling a Viscount BB to use a FG might be hard. you need to find a spindle the correct size for the cranks you wish to use but also the type use in a press in BB. the VO BB may still be best way to go

pics?

Of course, once you account for the time you will spend polishing off that garish anodizing, you might just about break even.

I'd really like to hear about anyone succesfully using that vo bb in a viscount. The id of the bb shell, or the od of the bearings, is right at the limit of what that bb is supposed to work with. There may also be some assymetrical issues for the lengths of the original spindle. Then there are the frame tubes usually intruding into the bb shell that would probably need to be ground out to use that bb. Too bad it's so complicated, those are nice frames. I'd like to hear what happens with this one.

So I did it. for the re-install i put the axle in a vice and tapped it down onto its bearing ( lightly) Then i inserted this axle/bearing combo into the frame and tapped it in with a rubber mallet, old axle, and an old headset race. Did the same for the other side. I had to play around with some light taps to get the bearings seated evenly on both sides. You can tell they're seated right when the grooves for the c-clips on either side are just visible. Slipped on the clips and sent it out the door. I managed to do a couple of long skids on it ( customer didn't have clips) and the bb seemed alright.

If anybody wants to trade some parts for a 58cm plus viscount frame and bb I'm all ears.

Future readers database update:
I found a stronglight threadless BB and there is no chamfer on the lockrings, it mounts flush to a standard faced bottom bracket shell. This means the frame does not require a rare tool to prep but also does not self center and can fit fairly loose in ITA BB shells.

I think that I have a very old CCM with this type of bottom bracket. Do you have any more info, or know of a place that I may buy/rent tools?