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Old 02-17-11 | 08:04 AM
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French Threaded Crank

A while ago I picked up a Stronglight 93. It's a beauty. Well, it was marked as english threaded. I recently put it on a bike.

It's french threaded.

hence my ISO posts for french threaded pedals.

So, I think I can have the threads retapped to english since Frenchy threads are smaller.

It would exponentially open up my pedal options. Not to mention if I use this bike for a brevet (which I most likely will), I'll probably throw spd's on it. I'd like to be able to do that without changing the beautiful crank out.

In fact I don't even have a puller for this crank yet.

So, any opinions on re-tapping? I'm not sure how I feel about modifying an original piece like this, even though it's most definitely the practical answer.

What would you folks do? It's only original once or just retap it and be done with it?
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Old 02-17-11 | 08:07 AM
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Retap and be done with it. Even better, retap and helicoil, the threads will hold better.
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Old 02-17-11 | 08:10 AM
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All of mine are retapped. Helicoil? Ridiculous!
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Old 02-17-11 | 08:13 AM
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The crank was marked as English threaded or the auction was marked as such?

I ran into the same issue recently. I was going to tap my 93 but had the same reservations. I began looking for pedals and found a couple pairs of Lyotard rat traps. I really like them with clips and straps. Now I have two French threaded 93s and no real desire to tap them to 9/16" x 20.

The Stronglight 93 was not a rare crankset by any means so far as I know. If you're a dedicated SPD guy then I don't see an issue having them tapped or you could just continue to look for one that already has English threads.




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Old 02-17-11 | 08:20 AM
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Originally Posted by Grand Bois
All of mine are retapped. Helicoil? Ridiculous!
i was actually hoping you'd chime in, and I was expecting you to yell at me for considering the retap

Originally Posted by ColonelJLloyd
The crank was marked as English threaded or the auction was marked as such?

I ran into the same issue recently. I was going to tap my 93 but had the same reservations. I began looking for pedals and found a couple pairs of Lyotard rat traps. I really like them with clips and straps. Now I have two French threaded 93s and no real desire to tap them to 9/16" x 20.

The Stronglight 93 was not a rare crankset by any means so far as I know. If you're a dedicated SPD guy then I don't see an issue having them tapped or you could just continue to look for one that already has English threads.
the auction was marked as english thread. That, or even more likely I didnt read it entirely and just bid at the last minute...

I WAS a dedicated spd guy, but I've started riding platforms on some bikes and it's starting to grow on me. That said platforms are ok for a short ride, but I don't think I'll be switching over for longer stuff.

I guess I'll see about having Curtis at Via retap..it's the last thing keeping me from finishing this bike and I want to ride it!
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Old 02-17-11 | 08:22 AM
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Originally Posted by -holiday76
I guess I'll see about having Curtis at Via retap..it's the last thing keeping me from finishing this bike and I want to ride it!
The Carlton? The little 4M adjuster should be delilvered to you today.
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Old 02-17-11 | 08:23 AM
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Originally Posted by ColonelJLloyd
The Carlton? The little 4M adjuster should be delilvered to you today.
i'm not telling.
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Old 02-17-11 | 08:24 AM
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Tap 'em! I bought a set of the Park pedal taps a while back, and they've been invaluable.

Neal
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Old 02-17-11 | 08:24 AM
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Originally Posted by -holiday76
i'm not telling.
I suppose that's better than telling and NOT showing.
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Old 02-17-11 | 08:29 AM
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Originally Posted by ColonelJLloyd
I suppose that's better than telling and NOT showing.
soon enough. two more minor details and the pics will be flowin'. I've been trying so hard for the past few months not to show anything until I'm done on the 3 builds I have going on.
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Old 02-17-11 | 08:30 AM
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Originally Posted by nlerner
Tap 'em! I bought a set of the Park pedal taps a while back, and they've been invaluable.

Neal
that would be these right?

https://www.treefortbikes.com/product...l-Tap-Set.html

maybe I should just get a set since I'll probably spend half of that having someone else do it.
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Old 02-17-11 | 08:31 AM
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You could just see if anyone has a set you can borrow. Come to think of it, I have a set you can borrow. Problem solved.
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Old 02-17-11 | 08:32 AM
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Originally Posted by -holiday76
that would be these right?

https://www.treefortbikes.com/product...l-Tap-Set.html

maybe I should just get a set since I'll probably spend half of that having someone else do it.
Yup, those are they. You'll also make your money back with what you save buying eBay cranksets that *are* marked French threaded. They usually go for significantly less than English threaded.

Neal
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Old 02-17-11 | 08:33 AM
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Originally Posted by nlerner
Yup, those are they. You'll also make your money back with what you save buying eBay cranksets that *are* marked French threaded. They usually go for significantly less than English threaded.

Neal
Shhhh! Shush it!
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Old 02-17-11 | 08:34 AM
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Originally Posted by ColonelJLloyd
Shhhh! Shush it!
It did occur to me that I just gave away a C&V state secret. Well, not anymore.

Neal
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Old 02-17-11 | 08:34 AM
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Originally Posted by nlerner
Yup, those are they. You'll also make your money back with what you save buying eBay cranksets that *are* marked French threaded. They usually go for significantly less than English threaded.

Neal
that's probably why I scored the one I have so cheap, come to think of it...
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Old 02-17-11 | 08:55 AM
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The T handle for the taps may cost you almost as much as the taps. I used an adjustable wrench to turn the taps until I broke down and bought one. Very little material is removed and the taps go through the aluminum like butter. It's not even necessary to remove the crank from the bike.
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Old 02-17-11 | 09:08 AM
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Originally Posted by nlerner
...you save buying eBay cranksets that *are* marked French threaded. They usually go for significantly less than English threaded.

Neal
Conversely, it seems to make French threaded pedals more valuable. I sold some Frenchy threaded Lyotard 45CAs on ebay last summer and got twice what I thought I'd get.

I've retapped a dozen or so Frenchy threaded cranks... I wouldn't hesitate in recommending it.

Last edited by Noah Scape; 02-17-11 at 09:50 AM.
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Old 02-17-11 | 09:11 AM
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LBS did my LA Cyclotouriste's for 10 bux.

after seeing how well it worked I bought a Tap and Die set from lowes that included a handle, the taps and the Dies to cut threads on a bolt. Just used em last night to thread a hole for a fender mount. Infinitely useful!
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Old 02-17-11 | 09:49 AM
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Originally Posted by Grand Bois
The T handle for the taps may cost you almost as much as the taps. I used an adjustable wrench to turn the taps until I broke down and bought one. Very little material is removed and the taps go through the aluminum like butter. It's not even necessary to remove the crank from the bike.
I also used to use a small crescent wrench to turn the tap, but then I got a real handle at a used tool/junk store. Very old school and cost $1.

Neal
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Old 02-17-11 | 10:24 AM
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Most bike shops will have a set of taps in the drawer, somewhere. Chances are they will be a great help if you approach them. And, for what it is worth, I too have purchased a set of taps, keeping in mind that you will need the proper taps, both right and left hand thread.

As for the helicoil idea - not!
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Old 02-17-11 | 11:08 AM
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Originally Posted by -holiday76
the auction was marked as english thread. That, or even more likely I didnt read it entirely and just bid at the last minute...

I WAS a dedicated spd guy, but I've started riding platforms on some bikes and it's starting to grow on me. That said platforms are ok for a short ride, but I don't think I'll be switching over for longer stuff.

I guess I'll see about having Curtis at Via retap..it's the last thing keeping me from finishing this bike and I want to ride it!
Are the arms marked as English thread? Look on the back of the arms -- French thread will have "14 - 125" and English will have "9/16 - 20"

If they're marked English, chances are they just need to be chased out. If they're French, you may as well tap them anyway to allow a wider selection of pedals.
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Old 02-20-11 | 06:42 PM
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thanks rhm for the taps. they worked great! I now can put my carbon fiber spd's on my '68 Carlton. Should look great.
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Old 02-20-11 | 06:47 PM
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I'd like to see a picture of this...

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Old 02-20-11 | 07:25 PM
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Originally Posted by DRietz
I'd like to see a picture of this...

soon, very soon.
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