I've been reading the thread currently going on about French bottom brackets. Very useful info there on replacement cups and the like.
I starting this so as not to hijack that thread. I have a question about my Astra BB.
I know or at least read that these are rebadged Motobecanes. So before I go tearing it apart I was wondering what the BB cups are thread wise. I have seen somewhere that some are Swiss and thus have a different rotation on the threading like lefty loosey or the other way around. I'm kind of confused.
Also would like to do the upgrade and have some great posters here help me in learning the right parts to use but wonder if the threading thing is gonna mess with me if it is backwards form normal.
Anyone can advise?

Have you taken your current BB out? If not then do it and pay attention to which way the cups thread out...The Swiss threaded BB's don't come up as often as French but about 1 a month does show up on da 'bay....The best option if it is Swiss is IMO the Phil unit. You can then get the BB with the correct spindle length and taper for the cranks you want to use. You could also just buy the Phil rings and use a Shimano UN72 if you can find one in the right length for your desired application. The only issue with that is you will be limited to using cranks with that taper. It's a cheaper route to go though....Got pics of the bike or have you narrowed down the year?

Where do you expect people to find all of these UN72's you keep recommending? They've been out of production for years.

I won one on eBay back in Oct. for $11.50. It now resides on my Dawes tourer with some Phil Wood English rings.

Neal

The chances of finding one in the length you need are pretty slim. The odds will be much worse a few years from now when you need a replacement.

Yes, this is very true. They always tend to be on the short side as well. I've yet to find one myself over 115.

you don't need a UN72 https://house-of-yes.com/phil-wood-y-bottom-bracket/

They pop up constantly on eBay, I've found 3 at a bike co-op, and I've pulled several form old MTB's that functioned just find.....Where do people find things like NOS TA or Campy anything that have been out of production for 30+ years? They aren't that rare. If someone is patient enough it can pay to find one....Just sayin'. Sadly I only have 1 left which I'm keepin' for a Raleigh project.

Here is one that I found after all of 30 seconds and a search for "BB-UN72"
https://www.buckinghambikes.com/produ.../BBUN72_68x115

And another.....
https://www.jejamescycles.co.uk/id25641.html

And yet another.....
https://www.cinematechhosting.com/bic..._Brackets.html

It looks like each of the first two sites has one and the third has none.

I'll stick with my cup and cone bottom brackets. I know I'll be able to get bearing balls ten years from now.

I've seen that. I want to try it just because I like to tinker.

I tried the Phil rings with a Miche BB. It didn't work.

Alrighty then!! This Astra is got me turned around.
When I pulled the pedals which are marked with the famous M batwings for Motobecane one (drive side) was threaded for left loosening-right tightening. The other was threaded for left tightening-right loosening. Easy to pull and they came right off after I fiqured which way to go. The cotters gave me no problem as the came right out with a coupla bangs which made my day! The drive side crank slipped off easy and showed no issues but the other side crank seemed very loose(even before I pulled the cotter). Not up and down but side to side at a right angle to the spindle. I wonder if the crank spindle hole is egged. Wonder if the new cotters will tight up the slop.
Pulled the drive side lock ring and cup,spindle and bearings. The cup was left loosening-right tightening. But the fixed cup....dang if I can get it to budge either way .....ARGH

BTY still trying to figger the year. On the BB is a stamp oval with 1809 inside if any one knows...thanks

Welcome to the world of French bicycles! First off, you can forget all the ideas above about using a Phil Wood or UN72 BB unless you are planning to replace the crankset as well. Those BB's all use square spindles and yours will have keyways in the spindle for the cotters. Also note that French cotter pins are a different size than others so if you do replace the pins make sure you get ones that are correct for your spindle. That could be why the one crank is loose.

The fixed cup should be on the drive side and if it's French threaded it will be left loosening, right tightening. These cups are often VERY tight to prevent them from loosening with use. That is why most BB cups today are left-threaded on the drive side. You could find out what type of threading is on the BB by comparing that cup to another know ISO cup. French threads are 35x1 and ISO are 1.375x 24 or something. Check my math but I think 35mm is slightly larger than 1.375"

Finally, if the BB races are in OK shape you can just leave the fixed cup in place and rebuild the BB as is. Just put in new bearings and grease and go. Of course, if it's shot or you just want to upgrade you'll have to get it out. There are lots of tips on how to get stuck BB cups out posted around here but I would try to find out what type of threads you have first.

wasnt there something around suggesting that you could have a french threaded BB retapped to italian thread? or am i thinking of something else?

The NDS cup is always right hand threaded to my knowledge.
https://sheldonbrown.com/harris/botto...ets.html#sizes

It sounds like your cups are swapped. That would make it a pain to adjust with the chain rings in place.
OTOH, I've heard of people using adjustable cups on both sides to fine tune a chain line. I imagine that is getting harder to do, considering the scarcity/expense of parts.

I believe Motobecane was one of the first French companies to shift over to "Swiss" threads. Same 35 x 1 mm. threading as French, but the the drive side is threaded just like British fixed cups (= tightens turning counter-clockwise). Reversing fixed and adjustable cups on French threaded bikes was one of the sometimes oddly convenient quirks about French bikes.

The practicality of having adjustable cups on BOTH sides, possible with French cups, in some ways carried over to Phil Woods and eventually to many other cartridge BB sets during the 1990s. Companies such as Synchros... World Class...and Race Face quickly come to mind. This was possible since the entire cartridge barrels AND their lock rings - all fitted within the BB shell of the frame and could simply be shifted slightly to the right or left. Unlike the Phil lock rings, the threads of some just wrapped around the cartridge units (just like Campy and Shimano)... but, unlike Shimano & Campy they had no outer flanges to limit the movement of the drive side cup.

Unfortunately, these seem to have disappeared these days, along with the vanishing of the traditional square tapered spindle. Pretty slick and even rather reasonably priced - considering the overall quality... while the market had still made them marketable.
You may be able to snug it up with new cotter pins. Be advised that there were indeed two common sized pins used. For British pedal threaded crank arms 9.5 mm was common... for French diameter crank arms, smaller pin openings for 9.0 mm pins was standard. Unfortunately nothing is that simple.

Nervar is one company which comes to mind. By the 1970s they made cottered cranks for: ...
1.) British cotter pins + spindles & British pedals...
2.) French cotter pins + spindles and French pedals...
3.) Combinations of French cotter pins + spindles with British pedal threads.

Best to go to a competent local bike shop and have them measure the crank arm openings for the proper diameter pins. New replacement cotter pins are still available and may cost as little as $1 each - complete with new nuts and washers.

If you use too small a size they might "seem" to fit - at first, but could tend to slide too far down into the crank arm when fully tightened. Pins which are too large would be pretty obvious - since they would simply not fit into the crank arm bore at all.

Harris Cyclery has the cotters you need for $1.95 each.

I'm going to use Sheldon's Big Bolt method to try and pull the fixed cup out when I get home tonight I cleaned the inside of the braket and think I will be able to see the threads well enough to tell if they are left or right. I want to get it out before I take the frame to the PC shop
The cranks are UNIVERSAL brand if that means anything. The one that was loose had the cotter WAY in so either the cotter was replaced with a wrong size or it was ground down to much or damaged but It didn't look like it really. I really want to keep the bike OG,I kinda like the look and feel... I know I know!!! saving this set up is a total waste of time and I just need to upgrade. But how much to spend on a low end Hi Ten.......

Thanks all for the input

UO-8's are your largest source for cheap and effective French BB cups. Not light nor pretty, but an excellent source nevertheless.

-Kurt

Why not just keep what cups you have? I'm not a French expert, I just tend to keep whatever came with the frame... As far as I know, other than cup threads, French and English use the same dimension spindles (at least in the Campagnolo stuff I usually work with).

Yes, there are 2-3 different diameters for cotter pins; I take one to the bike store and let them figure out the right size. The taper needs to be filed to fit correctly!

French pedal holes can easily be tapped out to British.

There are always random French and Swiss thread pieces on ebay. Be patient!

Also, unless the frame is going to be painted, there's no reason to take out the fixed cup unless you're replacing it.

The Motobecane Grand Record I just picked up appears to be a 74 from the component dates, would that have french or swiss threads? I cant check for myself until I track down a TA crank extractor.

Actually, I don't think an Astra is really up to an UO-8. I flipped one few years back and I don't really recall the quality but
I seem to remember that it was sort of a step down from the UO-8. Certainly I would question going to the expense of getting a
Phils BB.

You just need to find a spindle that's made for thin cups or a spindle for an Italian BB.

I agree that it's better to leave the fixed cup in place.

Then what are you waiting for? Strip a UO-8

-Kurt

Oh great, now there's going to be a bunch of posts asking, "Where can I get French BB cups for this UO8 I found?"

Sometimes I think I should just invest in having some Chinese factory make up a 1000 or so thick shelled French threaded BB cups that would fit standard size spindles. They wouldn't have to be top quality - buy Phil's if you want that. Just basic, serviceable UO8 quality. How much could the things cost? There are so many little pieces like that that are such a PITA to find but could be supplied by some Chinese company for next to nothing.