Classic & Vintage - Wrestling with a difficult french frame

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mattface
03-05-07, 09:10 AM
I picked this pretty white Peugeot Mixte frame out of the pile at the local bike coop. It's a very neat looking frame, and I though I could make something kinda nifty out of it to sell in the spring fundraiser. Unfortunately it's fighting me all the way. someone had jammed a too big stem in with so much force that I had to cut it off, and am now trying to cut it out of the fork from the inside, what a pain.

The other frog specific problem is just as vexing. I was able to get the bottom bracket out, but was unable to get the drive side of the crank off the spindle (cotter bent over), so the drive side cup is trapped until I manage to cut the crank off the spindle. I think I should be able to use an italian spindle with the french cups. I would be even happier to discover I could use any italian threaded BB, but I figure it's almost certainly french considering the stem diameter is clearly french. I'm planning to use a square taper instead of cottered cranks.

So I guess the specific questions are this: Any suggestions for getting the end of that stem out? I've already cut a ways through it from the inside with a hacksaw, but it's still not budging, and I'm nervous about cutting into the fork tube. Any insight into getting a square taper bottom bracket to work with or without the original cups. Any other advice or ideas about working with french frames that I might be overlooking are also welcome. Thanks

(Cross posted to Mechanics forum)


evwxxx
03-05-07, 09:25 AM
Yuck, I had to do exactly that with a stuck stem on a Trek. The stem may have actually been the right size, just corroded and metalugically attached to the head tube. The stem I worked on did not come out until COMPLETELY cut thru all the way down the length of the stem. Now, I have learned here on BF that there are ways to chemically treat the alloy stem (I presume it is alloy?) that will eat away at the aluminum, eventually freeing the stem from the steel. Do a search on here for answers, I forget the actual chemical to use just now :(

ollo_ollo
03-05-07, 09:31 AM
Assuming you slready tried penetrating oil without success, some people report success soaking in an ammonia solution. If you are careful, you should be able to cut thru the aluminum stem the rest of the way without damaging the inside of the head tube, then maybe use a headset removal tool to drive out the stem shaft?


tolfan
03-05-07, 09:42 AM
Getting a stem out of the fork the old way is to clamp the fork in a vise heat it with a torch put a steel rod in the bottum and bang the #@%& out of it with the bigest hammer you have.

vjp
03-05-07, 10:20 AM
A French steerer tube has an inside dia. of 22mm and people frequently jam a regular stem that has a 22.2mm diameter into them. I would do what Tolfan suggested but see if you can get the stem wedge to fall out the bottom of the steerer first and then try and find a rod that will fit inside the stem all the way too the end. Place it upside down in the vise so the fork crown is straddling the jaws and the steerer tube is not clamped tightly. You probably don't even need the heat if you have a good solid rod and a heavy hammer.

vjp

mattface
03-05-07, 12:22 PM
yeah, that's part of the problem. the stem wedge it too big to come out the hole in the bottom, so the wedge is rattling around in there getting in my way when I try to poke something through the bottom to whack it with.

Poguemahone
03-05-07, 03:28 PM
You'll likely have to drill out the cotter pin on the drive side crank. Takes a while, requires a power drill, but can be done (I've done it).

You are correct about the italian spindle, kinda; what you need is an italian spindle made for Japanese cups (labeled "5" in the Japanese numbering system). Alas, the "3" spindles are way more common. I suggest getting a set of Sakae/Sugino French threaded BB cups, available on ebuy for @20$. They'll work fine with the more common "3" series spindle. The issue is the thickness of the cup wall; the Suginos have thicker walls than the original french cups on your bike. The switch to the Sugino cups is pretty much SOP on French beater bikes I rebuild; takes away a load of problems.

Getting Italian stuff to fit the BB requires retapping, why bother when the Sugino cups are available?

braingel
03-05-07, 03:33 PM
If you use a hacksaw to cut the bent cotter pin off flush with the crank, you can use an old pedal spindle as an intermediate between your hammer and the pin. Spray some WD-40 in there and let it sit for 10 minutes, and then give it a really hard whack. And another. And another...

evwxxx
03-06-07, 07:36 AM
Ummmm,,,you guys know there is such a thing as a cotter pin removal tool at your LBS, right? (At least, if your LBS has been around for awhile). I used one just the other day to remove cotters on my 72 Raleigh Supercourse. Slick as a whistle! I had already pounded on them for awhile, to no avail.

In this particular case, since the cotter pin is apparently already bent, it may need to be tapped back up straight with a hammer. Going a little more than necessary in this process should reduce tendancy to bend back over when force is applied.

John E
03-06-07, 08:45 AM
I remember the big old VAR cotter press at Bikecology. evwxxx is right -- that is the weapon of choice for this application.

ilikebikes
03-06-07, 01:02 PM
I picked this pretty white Peugeot Mixte frame out of the pile at the local bike coop. It's a very neat looking frame, and I though I could make something kinda nifty out of it to sell in the spring fundraiser. Unfortunately it's fighting me all the way. someone had jammed a too big stem in with so much force that I had to cut it off, and am now trying to cut it out of the fork from the inside, what a pain.

The other frog specific problem is just as vexing. I was able to get the bottom bracket out, but was unable to get the drive side of the crank off the spindle (cotter bent over), so the drive side cup is trapped until I manage to cut the crank off the spindle. I think I should be able to use an italian spindle with the french cups. I would be even happier to discover I could use any italian threaded BB, but I figure it's almost certainly french considering the stem diameter is clearly french. I'm planning to use a square taper instead of cottered cranks.

So I guess the specific questions are this: Any suggestions for getting the end of that stem out? I've already cut a ways through it from the inside with a hacksaw, but it's still not budging, and I'm nervous about cutting into the fork tube. Any insight into getting a square taper bottom bracket to work with or without the original cups. Any other advice or ideas about working with french frames that I might be overlooking are also welcome. Thanks

(Cross posted to Mechanics forum)


I just posted this pic on another post, but I couldnt help but post it here too due to you title "Wrestling with a difficult french frame" :D How would you like to be "Wrestling with this difficult french frame! " with this french frame! LOL!

http://i5.photobucket.com/albums/y167/stumpyspic/coolbikeposter.jpg

mattface
03-06-07, 02:00 PM
How would you like to be "Wrestling with this difficult french frame! " with this french frame! LOL!

Would be more fun than the Peugeot probably, but ultimately less rewarding, since in the end I'll have a pretty nice bike and with yours only frustration and heartache.

Poguemahone
03-06-07, 02:37 PM
Yeah, I know about the tool for cotter pins, but the OP said the pin is bent. I prefer, own and use the Park press, but once the pin is bent, I've found the tool is pretty useless. Unless you can manage to bang the pin fairly straight and try with the tool again (after soaking the pin in PB blaster overnight). Otherwise, Drill time (urgh).