Hacksaws and Dremels, and chisels, oh my.

     We had a little problem. The right BB cup would not come out of the frame. Except that was really a big problem because this frame was a Ti Eddy Merckx and the BB was a 7700 Dura Ace.
     Right up front, I tried to turn it the wrong way. The frame was made by Litespeed and it was full D/A so I made an assumption that it was JIS. That was wrong, and it did not budge.
     Here comes the hard part, I had to allow that I had made a mistake, that I was WRONG. So rather than start wailing away at the BB(That came later), I measured the width of the shell. Sure enough, instead of the 68mm for JIS the shell was 70mm and that is ISO.
     For the curious JIS=Japanese Industrial Standard ISO=International Organization for Standards(I should write about these two)
     The key to this difference is that JIS(What you see on most threaded bottom brackets is JIS in either the 68mm or 73mm spacing) has a right cup with left hand threads. You remove it by screwing counter clockwise. ISO has both cups with right hand thread(Lefty Loosy, Righty Tighty).
     Corrective measures were taken and the wrench was turned the other direction with the same results, nada. This piece of equipment was not going to cooperate. And that is a real problem, because the Shimano Dura Ace 7700 bottom bracket (along with all the other 7700 bits) has been out of production for more than ten years. To add to that, they did not make many of the ISO spec, and this was a pretty delicate design so they did not hold up to years of use with out lots of maintenance.(And really, who maintains their bike?)
     First thing, I had to closely check the bearing surfaces. The 7700 BB used tiny(I mean really tiny. Usually loose ball BBs have 1/4 bearings, these were in 1/8th range) ball bearing sets. Without very regular maintenance the balls and races eat it pretty quick. And these were chewed up, so just greasing it and sticking it back together was not ideal. But it was a mark in the plus column for destructive removal of the cup. We might be able to find a correct BB via the internet. We could also install a new BB and matching crank with updated parts. After a talk about all the options with the customer, the decision was made to try and keep the bike original. Searching the wilds of the internet, I found an NOS(New Old Stock) in the original packaging.
     Now I could go to town. First, using a home brew rig to hold the spanner in place, I started tapping on the handle with a 16oz hammer. Eventually upping the force, I got nothing but tired. Next was the tried and true chisel. The only effect this had was to remove the spanner notches from the cup flange. Finally hacksaw and Dremel time, the fun begins.
     There is a hardened steel race set in this cup. and the hacksaw was never going to cut thru that. The dremel, however, loves this kind of job. Two cutoff wheels later the race popped out with a screwdriver. Now comes the delicate part of the operation, hacksawing thru the cup, in two places without cutting in to the titanium frame. You have to pick a spot where you will not hit the bike frame with the hacksaw frame. Then you take the saw apart and reassemble it with the blade running thru the shell. Carefully cut as square to the shell as you can, checking often to make sure you are not going in to the threads. You don't need to cut all the way thru the cup, just to the tops of the threads. Then it acts like perforated paper and comes apart pretty easy.  After you make this cut, without screwing anything up, you get to do it again, about 20 degrees away.

As you can see, I spared no indignity to this cup trying to remove it.

        Once you get the slots cut, remove the hacksaw, take your jim dandy chisel and hacksaw and knock out the small pie slice.   Now there is plenty of room to crush the cup and, Bobs your uncle, it is rolling across the floor, trailing a black streak on the new flooring.

 

 

     It turned out that the person assembling the bike had not used ti-prep when installing this part. Titanium is a great material for building bikes. It is tough, corrosion proof, and springy. Only problem is that it does not play well with others. You tear up tools cutting and shaping the stuff and Ti seizes to nearly every other kind of metal, especially aluminum. (I once had a Ti screw seize in an aluminum stem as I test fitted it with only finger pressure.)
     The replacement part. received plenty of coppery ti-prep and as is the nature of ti-prep everything ti came in contact with has a permanent coating as well.