BB removal...!
 

I have mentioned a project that I am working on. It is a Hercules 26" frame and I need to replace the bottom bracket. I have removed everything except the "fixed cup"(?) on the drive side. The part has for holes in the face for what I think is a spanner wrench. The spanner wrench WON'T WORKThe problem is that I can't get the thing to budge AT ALL. It is "frozen" in place. Does anyone have a suggestion for the removal of this part? My camera broke and my wife's doesn't like my computer so I can't put up a picture!

First there is no way that a spanner is going to budge that fixed cup. Check Sheldon's method or just have a shop do it. http://sheldonbrown.com/tooltips/bbcups.html

Secondly the Hercules almost surely has 26tpi "Raleigh" threading, which means you may have a difficult time finding replacement cups if needed. Google threadless bottom bracket to see other options. You will need to refer to Sheldon's page on chainline to make sure you match the BB to the crankset and rear cog(s).

It is seldom necessary to remove the fixed cup. Is it worn to the point that it needs replacement? If not, leave it in place, clean the inside with a cloth dipped in solvent, repack and be happy.

here's the deal. I am replacing the crank and bottom bracket. The crank is going to be an FSA Gimondi and the BB is a RPM bb 7420. The both fit and think should be all OK in the alignment. I didn't plan to use the bb in any event. Now I just need to remove the fixed cup. The lbs looked at like I had "rocks in my head" when I asked about the removal. They said that it wouldn't be usable after the removal, Not a problem! I quess it's time to get out the NEW hacksaw blade and start cutting!

Decent bb cups are VERY hard and will ruin most hacksaw blades in a few strokes. You need a carbide blade, or better yet clamp the edge (assuming it has an accessable edge) of the fixed cup in a sturdy bench vise and use the frame as the lever to turn it out. If it has Raleigh or English threading be aware that the fixed cup is left-hand threaded and removes the opposite way from "normal".

Check the sheldon site as there is a detailed discussion on this.

It is likely that your new bottom bracket will not work. The Nottingham built Hercules bikes were likely to have 26 tpi threading while your new BB has 24 tpi. To use you would have to have a bike shop retap the bb shell, and then it may give you problems. You really need to measure the thread pattern. If it is 26 TPI, I'd recommend using the old cups and put a new tapered spindle in it. You may have to experiment a bit to get the right spindle length. Also, have fun with cutting the cup out - buy a couple of dozen hack saw blades.

Did you buy the FSA cranks yet. I just put a set on my bike. They look good in the catalog but in real life they are a bit too clunky for me. They are the right price, though.

-G

checked the sheldon brown site. he shows an inexpensive homemade tool that I am going to try.
I'll bet I can even "screw" this thing together :)


http://bikeforums.net/attachment.php...hmentid=297249

I'd be dribbling some aerokroil around the threads of that thing now, tomorrow, and the day after when you actually attack it. dribble it in on both sides of the threads. just before you're ready to remove it, ice down the fixed cup so it as cold as you can get it, then apply mild heat (hot air gun, not blow torch) to the BB shell, try and get as much temperature differential as practical, THEN go postal on the big tools.

have you found a raleigh 26TPI threaded BB ? as several people said, the vast majority are 24T 'british' which is totally incompatible.

Sheldon's tool does work if you get it TIGHT and turn it the correct way. However, as gmt13 noted, if your frame has Raleigh's proprietary threading (26 tpi, not the much more common 24 tpi of English threading) very few available bottom bracket will work.

Phil Wood ($$$) does make Raleigh threaded cups for their square taper cartridge bottom bracket and sells Raleigh threaded external bearing bottom brackets for use with Shimano or SRAM cranks. Otherwise, they are not easily found and certainly not in other cartridge or external bearing formats.

what is "aerokroil" i've been using PB Blaster for soaking the threads. i'm not sure that I have a 26tpi threaded bb. all i know is that the trial old RPM7420 threaded in very smoothly without ANY binding. if the RPM unit is a 26tpi unit then i presume that by threading it in to the shell easily MIGHT indicate that the threads match. Is that valid ?

If the newer bb threaded in easily you are fine and, one way or the other, the threads match. Typically an English bb cup will thread into a Raleigh bb shell a couple of turns and then get obviously too tight so it doesn't take much to find out they are a mis-match.

aerokroil (aka kroil, from Kano Labs) is a penetrant, probably the best one on the market. PB Blaster is the 2nd best. :D

kroil comes from the airline industry.

...watch the fault lines!!!
I will attempt to locate the aerokroil. The PB Blaster hasn't touched it.
Thanks for the tip!!! The aerokroil might even get me out of tight spot!!!

as she said at the picnic,"...it went all the way in!!!" no apparent friction..!
so MAYBE what i'm tryingwill work.

You seem to have managed to find a Hercules with a standard british threaded BB. Unusual...

How unusual...?
Perhaps I should be careful with the parts. one side of the cottered crank will not come apart and it has suffered some "impact damage" on the key.

I have mocked up an RPM bb-7420 and it fits nicely. no resistance and no cross threading. I think I have a match.

If by "key" you mean the cotter pin, don't worry about trashing that if you have to, you can still get replacements. If you're having trouble getting it apart, Sheldon explains here and in more detail here if you're having trouble.

Not worried about replacing it. I am replacing the BB and the crank. FSA Gimondi and RPM 7420.

You may have one old enough to be pre-Raleigh and thus have the standard British threading. If you still have the headbadge, it will say Birmingham if it is pre-Raleigh, Nottingham if it was produced by Raleigh. By all means try to save the old parts, some of us are always on the lookout for replacements.

What do you plan to do with the old cranks? If this is truly a pre-Raleigh Hercules I may want to take them off your hands.

-G

I tried once to get a fixed cup off and gave up. I tried Sheldon's gizmo and it didn't work for me. I was going to replace an old Zeus BB with a modern Campy Chorus 10 speed. Instead I cleaned and repacked the Zeus BB and put the Chorus crank on it and it has been absolutely perfect ever since. Dead quiet, quieter than my sealed Mega-Exo outboard BB, and completely smooth. Not bad for a 30 year old BB/axle. The Chorus 10 made the chain dead silent too. It's a good thing they were both square taper and they matched.

Never saw a gimmick like that, but it seems to be a brilliant idea! SB was a genius. You could use a right hand threaded bolt/nut to remove left hand threaded BB races, and left hand threaded bolt/nut to remove right-hand threaded races.

My Most Toughest Fixed Cup...

Once I found out which way the threads went by looking from the opisite side I had to guy spot weld a 1" nut onto the cup and then broke it loose at a tire shop with an air driver and prejudice...

You don't even need the left-handed nut and bolt - if you use an extension bar and a ratchet, you can tighten the bolt from the other side of the BB shell to remove right-hand threaded ones.