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Discussion Starter · #1 ·
I picked up this very early McMahon Ti frame today with a frozen BB.
Usually I would not fool around with this but it was such a great deal that it was hard to pass up.
So I am wondering what my options, if any, are? The photo's show that someone tried but failed to budge it.
Any help would be great.
Thanks
 

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Judicious use of heat and candle wax into the threads .
 

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Experienced the same recently and it was a three day process for me. Two large aerosol cans of PB Blaster spraying the outside and filling the seat tube until the entire inside of the BB is soaking in it (drip pan underneath the frame). After a 48 hour soak I used a longer 8mm bolt and thick spacer to hold the pin spanner into the cup and then put a 4' long pipe on the wrench and got them loose. Best of luck to you!
 

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illuminaughty
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nice score...I saw that and almost moved on it, but I have WAY too many projects that I haven't even started yet. Post pics of the build.
 

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Discussion Starter · #7 ·
LOL. I was wondering if you saw it.
Yes, after meeting with the fellow he took less then his asking price because of the BB.
I figure this will be a fall project for those shorter days.:)
 

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Hybrid Leftys aren't real
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If the BB is shot anyway? Drill one of the existing holes out a bit, tap it to a 6mm thread (average stem bolt) and install a nice long, good quality steel bolt. That'll allow you to use a good sized crescent wrench, in conjunction with the spindle and possibly a breaker bar. Add in all the penetrating lube (and a 6er of some sturdy IPA) as mentioned, and you stand a fighting chance.....

Have fun:thumbsup:
 

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Neo-Retro Forever
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If you're not worried about salvaging the BB, as a last resort, you could drill some 1/16 inch guide holes all the way around the actual BB cups, about 8-10 mm apart. Using these guide holes, then drill with about a 3/8 inch bit, again, around the BB cups. You want the edge of these 3/8 inch holes to just about meet one another, and the external edge of them to be about 2 mm away from the edge of the BB cup.

What you're going for is to allow the BB spindle and the bearing to be knocked out the outside of one of the BB cups so you could then use a hacksaw blade to slowly cut through the alloy cup, thereby making a safe extraction from the shell.

With the spindle out, you should be able to knock the other bearing out of the intact cup before taking the hacksaw to it, too.

This will take time but, if done right, will net you one cool, usable frame and a bunch of aluminum to throw in the recycling bin!
 

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Just be cautious in trying to get that BB out - it looks like it is a McMahon Ti BB in there (check to see if the BB axle is titanium).

If so, then the cups on each side are really thinly machined aluminum, with the bearings right behind them without too much material.

I have one of these old BBs sitting around somewhere in the garage. Let me know if you want a few pictures of it to get a better idea of how to attach yours. A pin tool was the only way to install or remove it.
 

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Glorified Hybrid Owner
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gm1230126 said:
Experienced the same recently and it was a three day process for me. Two large aerosol cans of PB Blaster spraying the outside and filling the seat tube until the entire inside of the BB is soaking in it (drip pan underneath the frame). After a 48 hour soak I used a longer 8mm bolt and thick spacer to hold the pin spanner into the cup and then put a 4' long pipe on the wrench and got them loose. Best of luck to you!
Agree 100%.

PB Blaster got bolts loose on my buddy's '50 Ford that may have not been touched since it was made in 1950.

If that doesn't work, take an oxy-acetylene torch to the cups of the bb (if you don't plan on using it).
 
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