[CR]French bottom bracket threads


Example: Books

From: "Norris Lockley" <Norris.Lockley@btopenworld.com>
To: <classicrendezvous@bikelist.org>
Date: Fri, 13 Feb 2004 00:26:28 -0000
Subject: [CR]French bottom bracket threads

The French are always troublesome in one way or another.. if it's not their wine, it's their politics and if it's not politices it's their bottom bracket threads. Well Tom I hope that this is not the bracket shell on that super Urago track frame that you were telling me about.. great shame if it is.

The re-threading with Italian threads sounds a bit drastic, but as Urago usually used either an RFG or a Nervex shell, both of them with a bit of meat in them, there should be enough metal there to take the larger diameter Italian cut. Another possible way out of the problem is to find a Mavic or a Stronglight sleeved cartridge unit bracket of the type that just pushes through and locks up with a lock ring at each side. I know that these usually require some chamfering of the shell.. ideally.. but it is possible to get them to stay tight without doing this. That would be a solution if you intend using cotterless cranks

However.. if all else fails and you really do want to fit a cottered bracket in keeping with the frame, then I do happen to have a MAVIC reamer and thread tap combined which could be sped across the Atlantic. It's a precision tool that first of all reams to an accurate diameter and then recuts the thread accurately. Because the French threads are both R/H you can wind this tool straight through the bracket and obtain perfectly aligned threading.

Don't know what it would cost to get the thing to you.. but that Urago must be worth the expense.. or of course you could sell the frame to me.!

I shall be going over to France on Sunday to spend a fortnight or so in the Loire valley among the chateaux and 175kms south of Paris. On the way down by car I shall be passing dangerously near Herse, Singer and Gemini country. I'm just trying to calculate the total worth of an estate car loaded up with a boot full of their machines... it's got to be worth a small 10kms detour.

Let me know Tom.. I need to wrap the reamer/tap PDQ

Norris Lockley (...greasy rag on the go again.. must lace up those wheels tonight)