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Replacing French Threaded Fork (Motobecane)

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Replacing French Threaded Fork (Motobecane)

Old 01-17-24, 09:34 PM
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Replacing French Threaded Fork (Motobecane)

I did a dumb thing and bent my bike fork. I did an even dumber thing and road the bent fork for months. Fortunately, someone random on the street talked the senses into me (also inclimate weather helped).

I'm struggling to replace this French threaded fork, and it doesn't help that I have a tall bike (~230mm steerer length). I'd also like to not start changing it to ISO parts.

I'm curious what folks on this forum would do in my shoes. I've been camping eBay and searching around for weeks, and I haven't found a replacement. Given how important biking is to my mental health, I'm getting stir crazy.

Thank you!


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Old 01-17-24, 09:46 PM
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I know you just said you wouldn't but when I bought a similarly trashed Peugeot, I purchased a used Japanese fork. (I think it was a Bridgestone.) Bought both a French and an English Tange headset. Used the races that fit that part. Easy. (I did go English stem and bar as I was building up the frame from scratch.)

This does leave you with a lot of extra work with the handlebars, at least one lever, tape, maybe a shim ...

Edit: cheaper than mental health would be ordering just what you want from a framebuilder. I'm guessing a fork would cost one, maybe two visits to the shrink. No follow-ups required and much, much better long term prognosis.
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Old 01-17-24, 10:35 PM
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If this is your only bike, any chance of sourcing something in a similar size until you find a fork that works for you? Really tall bikes are sloooooow sellers and it could work very well in your favor.
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Old 01-18-24, 06:10 AM
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Originally Posted by collina
I did a dumb thing
You did something here not-dumb - how did you do it?

You posted as a total newbie - 2 posts and yet included a picture; I thought the system required people to have 10 posts.

Anyway, looking at that fork is cause to be glad you're alive.
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Old 01-18-24, 06:23 AM
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Originally Posted by collina

I'm curious what folks on this forum would do in my shoes.
That fork looks pretty high-end, along with French and tall. I'd do an ISO conversion so I could ride while doing the search for an appropriate replacement...thinking that might take a while.

Originally Posted by oneclick
You did something here not-dumb - how did you do it?

You posted as a total newbie - 2 posts and yet included a picture; I thought the system required people to have 10 posts.
Full member!
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Old 01-18-24, 07:25 AM
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Originally Posted by collina
I did a dumb thing and bent my bike fork. I did an even dumber thing and road the bent fork for months. Fortunately, someone random on the street talked the senses into me (also inclimate weather helped).

I'm struggling to replace this French threaded fork, and it doesn't help that I have a tall bike (~230mm steerer length). I'd also like to not start changing it to ISO parts.

I'm curious what folks on this forum would do in my shoes. I've been camping eBay and searching around for weeks, and I haven't found a replacement. Given how important biking is to my mental health, I'm getting stir crazy.

Thank you!



Well if you are adamant that don't want to change from french threading, then I really only see two options :

1) Continue looking for a french threaded fork or

2) Have a frame-builder weld your old french threaded steerer onto another fork.
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Old 01-18-24, 08:30 AM
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Wow! You must have went flying. I’m glad you are ok.

Was it a frame pump to the front wheel like in the movie ‘Breaking Away’? or the wild squirrel running across the road?

Your fork bend may be beyond realignment. Check your frame over real good, it may now have buckled or twisted.
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Old 01-18-24, 09:52 AM
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I don't understand why you would not just go to an ISO threaded headset top cup and nut.

There are some varables but the crown race should fit.

Absolutely no harm running a mismatch headset stack, I actually do it on several bikes.

/markp
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Old 01-18-24, 12:44 PM
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Originally Posted by Mr. 66
Check your frame over real good, it may now have buckled or twisted.
+1 That fork is pretty worked. I would be worried about the frame as well. Although admittedly we don't know quite what happened.
The more fundamental problem you have is you seem to only own one bike. You've come to the right place to be cured of that.
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Old 01-18-24, 01:23 PM
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-----

one simple solution would be a Tange Champion chrome replacement fork in metric dimension

they are fully chromed with a full-sloping crown and forged ends

the ones have employed in the past are for 700 wheel with 52mm brake centres

they even come in individual corrugated cartons




-----
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Old 01-18-24, 04:10 PM
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Originally Posted by 79pmooney
I know you just said you wouldn't but when I bought a similarly trashed Peugeot, I purchased a used Japanese fork. (I think it was a Bridgestone.) Bought both a French and an English Tange headset. Used the races that fit that part. Easy. (I did go English stem and bar as I was building up the frame from scratch.)

This does leave you with a lot of extra work with the handlebars, at least one lever, tape, maybe a shim ...

Edit: cheaper than mental health would be ordering just what you want from a framebuilder. I'm guessing a fork would cost one, maybe two visits to the shrink. No follow-ups required and much, much better long term prognosis.
My current rate is 2-1/2 shrink visits, and I throw in a half hour of listening to the customer crying about a broken fork.
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Old 01-18-24, 06:38 PM
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Originally Posted by oneclick
You did something here not-dumb - how did you do it?

You posted as a total newbie - 2 posts and yet included a picture; I thought the system required people to have 10 posts.
As BTinNYC mentioned, membership – it makes me happy when web forums with vibrant communities still exist and I try to support a bit. The site that rhymes with edit that triggers the profanity filters ate too much of the internet, but I digress. My apologies if I broke a newbie rule.


Originally Posted by due ruote
+1 That fork is pretty worked. I would be worried about the frame as well. Although admittedly we don't know quite what happened.
The backstory is silly, a bag slipped off my shoulder and went straight into the front tire. I went over, and my bike was mostly fine because, while it flipped too, it landed on my face as I was looking back to see what happened. Glad I wear glasses. The fork was moderately bent, but in the process of trying fix it, I made it substantially worse. I've always been a learn-by-doing person – learned several costly/painful lessons this time.


Originally Posted by due ruote
The more fundamental problem you have is you seem to only own one bike. You've come to the right place to be cured of that.
Originally Posted by AdventureManCO
If this is your only bike, any chance of sourcing something in a similar size until you find a fork that works for you? Really tall bikes are sloooooow sellers and it could work very well in your favor.
You are all wonderful enablers. I also appreciate the message that there's no need to be sentimental about keeping it French threaded. As an aside, I would have thought it would be easier to find things like this on the internet, e.g. international section of eBay, etc.

Like AdventureManCO mentioned, there's a few 62cm or so bikes that seem like they've been on the market for a while. It seems like the right strategy is either to switch it to ISO (and see how sentimental I am when considering shelling out money if anything pops up) or the Tange that juvela mentioned, or use this as excuse to "find a backup for the future."

Thank you everyone!
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Old 01-19-24, 12:22 AM
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I was kinda hoping you'd pick Gugie to build you the next fork. (He's 10 minutes up the road from me by velocipede.) Does good work and you'd get to pick any wild extra that crosses your mind. (Custom rack that bolts on neatly to carry that offending bag in civil but containing manner? Gugie would be just the person to come up with something that would look perfect. I have no idea what that would be but that's why you go to him, not me.)
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Old 01-19-24, 08:19 AM
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Originally Posted by juvela
one simple solution would be a Tange Champion chrome replacement fork in metric dimension
I don't think the Tange forks are available in metric dimensions, but that's not a show-stopper. French headset pressed fittings are the same dimension as ISO; only the threaded parts are different. Using the Tange fork would allow a much broader selection of headsets. But you may have to replace the stem as well.
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Old 01-20-24, 11:43 AM
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I have a chrome Motobecane fork with a 244mm steerer tube I bought in case the fork on my Peugeot PKN-10 couldn't be straightened. Long steerer tube French threaded forks being hard to find as you may have noticed. It's not an exact match for yours, the crown is like the Tange 124 in @juvela's post but it's straight, the chrome is in really nice shape AND I no longer need it. The downside is I paid dearly for it ( in my opinion, then again maybe not ) but it's available if you can't find an exact match.






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Old 01-20-24, 12:12 PM
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Originally Posted by Murray Missile
I have a chrome Motobecane fork with a 244mm steerer
That's more like a 180 mm steerer, since you mustn't tighten the stem quill in the threaded part. There's at least 60 mm of excess thread on that one (estimated from photo), probably more for optimal threading. I define the optimum as the minimum amount needed for the headset to screw on, which might leave the steerer more like 170 mm.

Putting that many threads on a steerer is criminal negligence. I don't use the word criminal lightly; I mean it is literally a crime and the company that did it should pay a hefty fine, whether or not anyone is injured when the steerer inevitably cracks. I know, I dreaming of a world where there is justice — dream on!

Too bad, I used to have a favorable opinion of Motobecane, but it's really only the mid-'70s and earlier models that I liked so well. Workmanship and designs were top notch at just about every price point.
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Old 01-20-24, 12:49 PM
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Originally Posted by bulgie
That's more like a 180 mm steerer, since you mustn't tighten the stem quill in the threaded part. There's at least 60 mm of excess thread on that one (estimated from photo), probably more for optimal threading. I define the optimum as the minimum amount needed for the headset to screw on, which might leave the steerer more like 170 mm.

Putting that many threads on a steerer is criminal negligence. I don't use the word criminal lightly; I mean it is literally a crime and the company that did it should pay a hefty fine, whether or not anyone is injured when the steerer inevitably cracks. I know, I dreaming of a world where there is justice — dream on!

Too bad, I used to have a favorable opinion of Motobecane, but it's really only the mid-'70s and earlier models that I liked so well. Workmanship and designs were top notch at just about every price point.
Ooh, good point! I forgot about that. I was going to use a NITTO Technomic stem or a LONG threadless stem adapter that put the wedge below the threads and have the OD turned down slightly to fit in the steerer tube. Although the OP would need to take about 15mm off the OAL and with the right stem it would put the wedge well below the threaded area so it still could work for them if they had no other options. Their call but very good that you pointed that out, something they neede to be aware of.
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Old 01-20-24, 01:00 PM
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Originally Posted by Murray Missile
Ooh, good point! I forgot about that. I was going to use a NITTO Technomic stem or a LONG threadless stem adapter that put the wedge below the threads and have the OD turned down slightly to fit in the steerer tube. Although the OP would need to take about 15mm off the OAL and with the right stem it would put the wedge well below the threaded area so it still could work for them if they had no other options. Their call but very good that you pointed that out, something they neede to be aware of.
I would be OK with using any quill that's long enough to always tighten below the threaded part. Just be sure to pass that warning on to any future buyer of the bike.
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Old 01-20-24, 01:04 PM
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Originally Posted by bulgie
i would be ok with using any quill that's long enough to always tighten below the threaded part. Just be sure to pass that warning on to any future buyer of the bike.

Definitely!!!
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