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-   -   Retro BB identification (https://www.bikeforums.net/classic-vintage/1200260-retro-bb-identification.html)

dvenman 05-04-20 08:55 AM

Retro BB identification
 
I can't post pictures as I don't have 10 posts yet. I'm trying to identify a BB on a retro (1980's ?) Rotary bike. The drive side has what looks like a big washer, about 35mm across, with two flats.

The non-drive side has a 24mm nut, and a lockring with 4 equally space notches.

If I can identify it I can get the removal tool, or work out what I need to remove it...

branko_76 05-04-20 09:32 AM

what's a "Rotary" bike ?

unworthy1 05-04-20 10:33 AM

post some more so you can upload a pic but from the mental image I get based on words written, I think maybe French, possible
"Lightrace" or Nervar. Here's something from Velobase, look familiar to you?
https://cimg6.ibsrv.net/gimg/bikefor...f5f3ae358.jpeg

dvenman 05-04-20 10:59 AM

That looks like it. I’ll post pictures as soon as I can.

The crank axle itself is a square taper, but those other bits look similar.

unworthy1 05-04-20 11:22 AM


Originally Posted by dvenman (Post 21454681)
That looks like it. I’ll post pictures as soon as I can.

The crank axle itself is a square taper, but those other bits look similar.

Her's a pic of a Nervar, this might be for a "Star" crankset but they made other models that used similar BB units. And by "Rotary" did you mean

maybe "Rotrax" ( a vernerable British make)?https://cimg3.ibsrv.net/gimg/bikefor...d46443110d.jpg

dvenman 05-04-20 12:43 PM

Looks promising. So a lock ring spanner, and a Park Tool HCW-4 or similar seems like it'll do the trick

branko_76 05-04-20 01:22 PM


Originally Posted by dvenman (Post 21454924)
Looks promising. So a lock ring spanner, and a Park Tool HCW-4 or similar seems like it'll do the trick

Your first post you state the fixed cup is 35mm, the Park Tool HCW-4 is 36mm so will not work. Also, the pins are useless for your bottom bracket.

I use a 12" adjustable wrench for my BB's that have 35mm fixed cups. My Diamond Tool wrench opens to exactly 35mm

branko_76 05-04-20 01:32 PM

For the lockring, this is a little more expensive than a Park Spanner but is much more versatile and easier to use.

https://www.mcmaster.com/5471a12


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