Bicycle Mechanics - removing cup-and-cone bottom bracket without special tools

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ghostm42
09-03-10, 07:56 PM
I recently inherited an old mixte frame and assorted parts. A "Made in France" Motobecane. It was neglected by its previous owner and many of the parts are seized (it took about 2 hours to remove the seat post yesterday). The bottom bracket either needs to be replaced or greased because it does not spin freely.
I got the crankset off after quite some effort (using a crank-removal tool). I got the lockring off the adjustable cup using a standard household wrench. I've removed adjustable cups before because they had wrench flats, but this is threaded all around. It does have holes around its surface, suggesting I need a spanner tool. But I don't have such a device and I prefer not to have to buy something I'd only use once.
Is there another way to remove this cup? Would a hammer/nail on the holes to create torque work (like removing the lockring on a freewheel)? Any suggestions before I damage the frame?
waldowales
09-03-10, 08:08 PM
I'd use a punch, rather than a nail, but adjustable pin spanners aren't very expensive, and won't deform the holes. I don't know if this one is big enough, measure the distance between holes. http://www.harborfreight.com/adjustable-pin-wrench-36554.html
badamsjr
09-03-10, 08:10 PM
These pin spanners are relatively inexpensive, so you may want to get the right one rather than chance damaging the frame.
kycycler
09-03-10, 08:16 PM
First, DO NOT use a hammer and nail.:( We call people who do that hammer mechanics. Yes, this is a derogatory term.:) Second, soak the cup with some sort of penetrating oil and let it soak over night. Go the LBS and get a pin spanner. Now you should be able to remove the cup. IF YOU MUST USE A HAMMER GET PUNCH OF THE PROPER SIZE AND TAP, NOT HIT HARD THE CUP.
reptilezs
09-03-10, 08:26 PM
make your own spanner tool. some sheet stock and some old drill bits or some nails.
A hammer and nail set or punch works better on a lockring than it would on an adjustable cup. By working better, I mean that it can get the lockring off but has a high probability of damaging the part. Track down or make a pin spanner.
Bianchigirll
09-03-10, 08:49 PM
if that frame says 'made in france' be gentle with the BB you may need to reuse it. take it to a shop and have it overhauled. it is easier and maybe the same price as finding tools
BCRider
09-04-10, 01:49 AM
Listen to B'girl. You may well have a french threaded BB that is more difficult to replace than you figure at first glance.
garage sale GT
09-04-10, 06:58 AM
A shop can pull the bb for you for a small fee even if you don't want them overhauling it. It may turn out to be pitted and useless and you can inspect it at home. Plus, make sure you are turning it the right way because French bbs did not use a reverse thread direction on the opposite side.
I guess you could probably reuse a pitted spindle by installing the crank opposite to the way it was before, so the fatigued area of the spindle is facing the other way. I have not tried this.
HillRider
09-04-10, 07:03 AM
I guess you could probably reuse a pitted spindle by installing the crank opposite to the way it was before, so the fatigued area of the spindle is facing the other way. I have not tried this.
That would work only if the spindle is symetrical. Most aren't and have a longer projection on the drive side.
The only wrong tool I'd attempt to use for the job you describe is circlip pliers.
...Or an unloved pair of longnose in a pinch
curbtender
09-04-10, 08:19 AM
Are you replacing or servicing?
fietsbob
09-04-10, 09:29 AM
There is a Kludge, requires a Big Bolt a matching nut and a stack of split washers ,
with that common hardware you tighten and clamp the fixed cup
then unscrew the cup via hardware clamped onto it.
dscheidt
09-04-10, 06:01 PM
Listen to B'girl. You may well have a french threaded BB that is more difficult to replace than you figure at first glance.
Depending on the date, it's either French (both sides properly threaded) or Swiss (fixed cup moron-threaded). SR bottom brackets (which is what it would have come with, unless it's very old, in which case it's french threaded) say how they're threaded, but it's sort of cryptic. The clue is that the cups on the opposite sides say different things, which tells you that one of them is moron-threaded. (bottom bracket cups don't precess off. the left threading serves only to annoy.)
garage sale GT
09-04-10, 07:19 PM
That would work only if the spindle is symetrical. Most aren't and have a longer projection on the drive side.No, I am referring to indexing the spindle, not reversing sides. Put it together so the pits are at 12 o'clock instead of 6 o'clock when the crank arm is at 3 o'clock.
ghostm42
09-04-10, 08:44 PM
Thanks for the suggestions so far. I do have a pin-spanner for a watch kit, but I doubt I can get enough torque with that. And with all the seized parts, I'm pretty certain I'll damage the pins on a lightweight spanner.
I'm not that familiar with all the different BB threadings. Which way is the adjustment cup supposed to be turned to remove it for French, English, Italian, Swiss, etc.? Which way for the removal of the fixed cup?
Granted, I have no clue what threading this might be. I can take a look at the threads when I'm back with the frame (away for Labor Day weekend), though I do recall seeing "Tange" on the cups if that's of any help. If my attempts fail with my limited tools, I believe I can rent bike work space for $8/hr (QuadBikes). They should have a spanner of adequate size. But the harbor freight pin wrench seems decent. Does anyone know if the pins actually fit or if they are replaceable?
JohnDThompson
09-04-10, 08:49 PM
There is a Kludge, requires a Big Bolt a matching nut and a stack of split washers ,
with that common hardware you tighten and clamp the fixed cup
then unscrew the cup via hardware clamped onto it.
Unless the fixed cup is damaged beyond redemption, just leave it in the frame. Removing it can be a major PITA, and re-installing it without the proper tools is unlikely to get it tight enough to hold securely.
JohnDThompson
09-04-10, 08:51 PM
No, I am referring to indexing the spindle, not reversing sides. Put it together so the pits are at 12 o'clock instead of 6 o'clock when the crank arm is at 3 o'clock.
That only works with headsets, which do not undergo constant rotation. It is pointless with a bottom bracket.
curbtender
09-04-10, 08:58 PM
Unless it's rusted in, that adjustable side should turn pretty easy now that you have the lock ring off. Wrap the threads a few times with duct tape and use some channel locks to spin it out. If you're having that much trouble on that side, forget the fixed cup side.
+1 forget the fixed cup without the right gear.
phidauex
09-05-10, 12:13 AM
The home-made tool described at the bottom of this page has saved me a number of times when it came to removing stubborn French BB fixed cups: http://www.sheldonbrown.com/tooltips/bbcups.html
Remember that if it is a French threaded bottom bracket, it will be "normal" right hand threaded, which means it was probably installed VERY tight so it wouldn't loosen itself over time. Expect it to be a bear.
-Sam
I had a dozen bikes like this when I was a kid and always I used a hammer and nail or punch. I did make a mess a couple of times but most times little effort was required to turn the cup.
garage sale GT
09-05-10, 06:41 AM
That only works with headsets, which do not undergo constant rotation. It is pointless with a bottom bracket.I'd say a headset cup or cone is more likely to be loaded across its entire face.
If the pits on the right of the spindle are turned around to face UP instead of DOWN when you are pedaling, there's no load on them. When you pedal the LEFT side, the pits on the RIGHT side face down, but the spindle is being levered so the RIGHT side is pressing UP.
However, it may still be a bad idea because Sheldon thought English spindles could be adapted to French frames and cups. If the old French spindle pits even a little more, the hard particles that crumble out can then ruin the cups, then you won't be able to rebuild your BB with an English spindle. So it depends if you're going to keep using the old cups, or just want to squeeze a bit more life out of them to see if you like the bike before spending $50 on a new VO bottom bracket.
garage sale GT
09-05-10, 06:45 AM
I had a dozen bikes like this when I was a kid and always I used a hammer and nail or punch. I did make a mess a couple of times but most times little effort was required to turn the cup.+1 it works. It makes little sense to buy the old BB tools if you're just using them to remove the old bb, although I seem to recall some of the VO French cartridges looked like they needed pin and hook spanners for installation instead of a Shimano-style tool.
dscheidt
09-05-10, 07:44 AM
I'd say a headset cup or cone is more likely to be loaded across its entire face.
You can say that. It won't make it true. The point of preloading an angular contact bearing is it keeps the bearing loaded at all points on the rotation. Pitting on a spindle is going to be the result of corrosion, which is going to have a lot more to do with how it was stored than how the cranks were mounted, or contamination, which will attack the whole race.
ghostm42
09-08-10, 10:32 PM
BTW, I got the adjustment cup out. It wasn't too bad, actually. I used a pair of needle-nose pliers, stuck them into the holes and twisted. With a bit of force, it came right out. The BB was filthy. A surprisingly large heap of dirt poured out, but with a bit of soap and water, it's spinning nicely again. Now... what to do with the stuck quill stem. I'll start another post for that.
corkscrew
09-09-10, 11:45 AM
Depending on the year of Motobecane, it may be swiss threaded, and not french.
EG, my 1984 Moto is swiss threaded, not sure when they made the change.
bringit to a car garage and ask them to help as they have large sprockets plus power tools ,i had the same problem with my old bike and the job was then done in about 30 sec when i took it to the garage
garage sale GT
09-09-10, 05:49 PM
You can say that. It won't make it true. The point of preloading an angular contact bearing is it keeps the bearing loaded at all points on the rotation. Pitting on a spindle is going to be the result of corrosion, which is going to have a lot more to do with how it was stored than how the cranks were mounted, or contamination, which will attack the whole race.It won't make it true, but the fact that you are dead wrong about the corrosion suggests you are wrong about that too.
Some forms of corrosion are called pitting, and they even look a little bit like bearing pitting to the untrained eye, but bearing pitting is caused by metal fatigue. The geometry of the situation means the stress is at a peak value somewhat below the surface. That's where the fatigue microcracks start, and they spread upward until a pit of metal crumbles out.
I suppose the bottom of a cone always pits because that's where the contaminants sink to, but the cup doesn't pit as quickly as the cone because the contaminants are floating on oil?
A headset crown race is always preloaded axially due to weight. And it is important to preload the upper races with correct adjustment-but it's not as crucial as the hubs.
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