Ive taken apart a vintage Gazelle Primuer. The bottom bracket that i took out is threadless. It was in place by plastic clips that attached to the frame (bottom bracket hole). This is a first for me and upto now im struggling to find a new one to replace it.

Can anyone help with this?

Widith of hole: 38mm inside/inside

Length: 70mm

Search for a Mavic 610 or Stonglight JP1000? Don't know if they'd work in a 38mm hole.

There were a few similar designs used 20-30 years ago. Unfortunately there was no consistency in the design of how the bearings were retained in the BB shell. If the spindle is OK you might source a pair of bearings (they're usually fairly standard), and re-engineer their retention in the BB shell.

Otherwise, you have 2 choices. If the BB shell is small enough - 1.310" or less - you can have it threaded to accept a standard BSC threaded BB. (or if 1.370" you can tap for a 36x24 Italian BB). Or you can look for a threadless cartridge bottom bracket similar to this one. It might require some modification of the shell, but one way or the other getting this bike back on the road should be difficult or expensive.

Hmmm, the ID of the BB-shell is 38mm or 1.50". I don't think we can thread it for any commonly available replacement bottom-brackets. Threadless BBs won't work either as they need the 33mm ID shell to press out against.

The only thing I can think of is to get a replacement English-threaded BB-shell from a framebuilder. Spin the OD down to 38mm or just over for a tight interference-fit. Then apply a thin layer of strong 2-part epoxy and press it into the current BB-shell. Now you can use any off-the-shelf replacement bottom-bracket.

Here's an item that might fit just right. You'll just need to trim off 1.5mm from each end to be 70mm wide:


https://www.cycle-frames.com/bicycle-...-LIGHT-BB.html

The OD at 38.1mm may be a little too tight to press in, so milling it down to 38.05mm should be about perfect.

I didn't notice the 38mm ID in your original post, so Danno is right you can't thread it, nor will common threadless cartridge BBs work.

I second his suggestion, but you can't use an interference fit. The insert's wall is too thin and if you try to press it in it'll either buckle, or more likely shrink in making the thread undersized. Best bet is to turn it down to a precise non-interference fit and bond it, or if it's steel, spot weld or silver solder in.

If you want to bond it, you can have a straight knurl at the ends, but will have to do the knurling with a threaded cup installed to support it during the knurling. Properly done, with clean seufaces and the proper adhesive, bonding should hold up fine. After all there's plenty of surface area.

Hi restore and all Gazelle owners,

although this comes very late, I still wanted to weigh in, since this post can be found when searching on google for "Gazelle bottom bracket".

I own an 80's Gazelle Primeur Special, and I have recently restored it. I live in Canada, but I have bought all my parts in Germany, where they are only about 1/4 of the price and readily available.

Gazelle has an odd size for the bottom bracket (I'm not sure if today's Gazelle still do, probably not). Those Gazelle bottom brackets are 38mm OD press fittings, 127mm length. You can find these parts very quickly when you start looking for replacements in Holland or Germany (I only look in Germany, since I don't speak dutch). I got mine from webbike.de

I'll just post a few links of pages where I found the fitting bracket. Maybe you can special order them to be shipped to the USA/Canada.

https://www.hollandrad.de/gazelle-inn...-thompson.html
https://www.webbike.de/onlineshop/inn...en-p-1200.html (sold out, the one I bought)
https://www.zweiradshop-krefeld.de/pr...-chamonix.html

BTW, the one I bought from webbike, seemed to just have had regular 40mm polyamide press fittings, that had been milled down (on a lathe) to fit perfectly into a 38mm bracket.

Cheers, Hans

Great info. I have just faced the same problem, I live in the UK and no bike shop has seen such a BB. Just placed my order.

Tip to remove the old Gazelle BB: The original BB was almost seized, I removed it by placing the frame over a solid fuel camping stove. The plastic brackets 'melted away' and the BB was removed with a few scrapes with a screwdriver and couple of taps of a hammer. The paintwork remained undamaged despite the intense heat. Bomb proof build quality on these bikes!

Rather than epoxy, I'd use Red Loctite Bearing Mount Adhesive. It's made for this kind of problem. Takes over 900 ft/lbs of torque or 900 degrees F to break that bond.