Classic & Vintage - Stronglight cranks and Olimpic Pedals. Tap it or JB WELD?

I got a "deal" on a Stronglight crank on ebay. It is new (or new old stock) and has French threads (14mm X 125).

I found some nice vintage looking Olimpic (Spanish) cage type pedals also with French threads. I am in the final stages of putting this Zeus Competition back together and found that the threads are very loose. The pedals flop around in the crank arms until they are fully threaded in. I know they will not hold up for long. I took it to a machine shop and determined that the pedals are on the small side, and the crank bores on the large side, so I have a perfect storm of tolerances at their respective (and opposite) outer limits. The machinist recommended JB weld! It is hard to put JB weld on brand spankin new parts! I have the option of buying a new set of 9/16" pedals and tapping out the crank, or gluing it up and riding it. What would you do????? Your suggestions are appreciated.

I would tap the threads to English and sell the French threaded pedals.

I would tap the threads to English and sell the French threaded pedals.

+1 ...
No way would I gob-up a Stronglight crank.

I would tap the threads to English and sell the French threaded pedals.

rhm is right, I think. I have a set of English-threaded Olimpic 64s that doesn't fit my French-threaded Stronglight 93. I'd consider trading pedals with you--on the condition that if your pedals are also loose on my crank (I don't know whether my crank threads are on the large or small side) that we trade back.
By the way, my engineer brother calls the phenomenon you describe--fit problems that result from one component being at the high end of the normal range, and a mating part at the low end--as "tolerance stack-up," which I think is kind of a nice phrase.

stupid question, I know, but did you try english-threaded pedals?

Highly unlikely in your case since NOS (nor would it be NOS, of course...) but over here many "14x125"-marked cranks you will find having been tapped to english threading.

stupid question, I know, but did you try english-threaded pedals?

Highly unlikely in your case since NOS (nor would it be NOS, of course...) but over here many "14x125"-marked cranks you will find having been tapped to english threading.

Good idea, I think. NOS means something has been kicking around a shop for a while, so there's no telling what's happened to it over the years.

+10 NOS is one of the most over-used terms on ebay. Can mean anything. Almost never does it really mean new.

Good idea qd-s I will try that right away. I appreciate auchen, rhm, and jonw comments too. That would have been "just not right". Tolerance stack-up, hmmm, I thought there must have been a name for it, thanks. The pedals are from Mel Pinto imports (Velo Classique) and were inexpensive (I think less than $50). I am waiting for an email from them to see what they will do for me. Okay I just went out to the shop, I did try that gd-s, and I believe you are correct!! A pair of English pedals I have threaded right in. The left one seems a bit loose, so I would not have had enough material in there now to tap them to English, because they apparently have already been done. I suspect that it was not a first class job, unfortunately. Jonwvara, I might be interested in a trade. I can chalk up another eBay SNAFU. I think I have finally learned my lesson?!?
Thanks again,

You could fix the threads, I was thinking of getting one these.

http://www.biketoolsetc.com/index.cgi?id=975709222636&d=single&c=Shop-Aids&sc=Thread-Repair&tc=Complete-Kits&item_id=BI-916K


http://www.biketoolsetc.com/index.cgi?id=975709222636&d=single&c=Shop-Aids&sc=Thread-Repair&tc=Complete-Kits&item_id=EL-2299

Wrap the pedal spindles with teflon plumber's tape before installing them.

207407
Jonwvara, I might be interested in a trade. I can chalk up another eBay SNAFU. I think I have finally learned my lesson?!?
Thanks again,

Well, the Olimpics I have are used, not new, so maybe a trade would be a little problematic. They have some miles on them and are kind of dirty--I haven't yet overhauled them--but the bearings seem perfectly smooth. Here's a photo.
If your pedals seem like a good match for me, I'd be willing to dismantle these, thoroughly clean them, confirm that the races are good, grease them and replace the bearing balls, reassemble and adjust. Let me know what you think. You can email me directly (easier than sending a PM) at jonwvara@yahoo.com
JV

207407

Well, the Olimpics I have are used, not new, so maybe a trade would be a little problematic. They have some miles on them and are kind of dirty--I haven't yet overhauled them--but the bearings seem perfectly smooth. Here's a photo.
If your pedals seem like a good match for me, I'd be willing to dismantle these, thoroughly clean them, confirm that the races are good, grease them and replace the bearing balls, reassemble and adjust. Let me know what you think. You can email me directly (easier than sending a PM) at jonwvara@yahoo.com
JV

A funny thing just happened: Out of curiousity, I just checked MY Stronglight cranks, which are also marke 14x125, and what do you know? They've also been retapped to English. I feel sort of foolish that I didn't check before posting the previous message, but there you are. I think I get more exercise jumping to incorrect conclusions about French bikes and parts than I do from riding them.
So I guess I'll stick with my English-threaded Olimpics after all. Sorry for the confusion.
JV

Hey man, very interesting. That is cool, I would like to see how the English threads feel in those tapped threads. I am tempted to get some non-permanent Loc-tite and start riding this thing. If that fails, I will go with the helicoil or insert. Please let me know what you think of the feel of the threads in your Stronglight crank.
Thanks,

Wrap the pedal spindles with teflon plumber's tape before installing them.

+1

Use pedal washers if you have them too.