7700 BB Saga/Rant

[oliver1850]

I've had a frame sitting here for a while with the superior threading and 7700 BB, acquired through the usual sketchy channels. Seller offered to remove the BB, but I figured it was safer to do it myself. The LH cup came right out but when I attempted to remove the drive side with the open ended Park tool (and already barked up notches) I had no luck. I was able to apply enough torque to wipe the notches several degrees from their original location, but couldn't budge the cup. I proceded to file two flats over the worst looking notches and tried a 15" adjustable wrench: nothing doing. So without checking to see what size sockets I had in the arsenal, I filed the cup to a 40 mm hex. Went out to the barn to get the socket set and found that I had a 38 and a 41, and the inch set went from 1.5" to 1.625" leaving out the 1 9/16" which would be the next size down from 40 mm. OK, now I'm making a wrench too. Found a 3' piece of flat stock at the farm shop about the right thickness, cut it down to about 15", scribed a hex from a pipe fitting about 36 mm, and drilled some holes. Cut between the holes with a chisel and started filing by eye. Fun keeping the flats parallel and the same width while removing 2mm from each flat. Ended up with a pretty good fit considering both surfaces were done by eye, but couldn't budge the cup pulling as hard as I could with the frame against my chest (because I was afraid to torque that hard on one tube in the stand). Hurt my hand and my chest. Don't know what torque value my weak self is capable of with a 15" lever, but pretty sure it's way beyond what BB torque is supposed to be. Next got the frame down on the floor on wood blocks with pipe foam around the tubes. Was finally able to move the cup a degree or two (tighter!) with my foot. Then went for 4 hour bike ride. After several hours of recovery I was able to remove the cup. I was really expecting Loctite given the superior threading, but as it turned out the problem was corrosion. The shell was basically clean, but had some water in at some point. Both cups had some threads damaged. I still wonder if Shimano did something with 9 speed era aluminum parts to MAKE them corrode as they seem to have corrosion issues far beyond any other parts I've dealt with. I've take aluminum Campagnolo cups out of frames that were much rustier than this one with no corrosion on the cups whatsoever.

Rant portion:

1.) why the stupid 6 notch interface on the DS cup? The cup doesn't look much different from the left one, which has 16 (?) splines. The Park tool for that is poorly designed, with a bevel on the end that prevents maximum contact area. At least the 16 splines provide enough area to overcome the poor design of the tool.

2.) why is the Park 6 notch tool open faced, allowing it to spread open? Their Campagnolo 111 mm tool is a ring, why not the 6 notch? I looked around to order a socket type 6 notch tool, but couldn't find one. I suspect that's the way the Shimano tool was made, but have never seen one.

3.) why not 39, 40, 41 mm (take your pick) hex interface on ALL threaded cups? I know, sell you another tool. Did Shimano really make any significant amount of money selling 6 notch BB tools?

[Peter P.]

Great story and a good dose of ingenuity!

I'm amazed the cup was so seized in the BB considering from the photo I don't see corrosion in the cup threads, just in that non-threaded area.

Did you try any liquids to break the bond such as Liquid Wrench, Kroil, etc? How about the usual lye or ammonia to dissolve the aluminum cup?

[Cat3roadracer]

I've had several corrode in Ti frames. Nice job with the wrench.

[Dale Alan]

Great job on that wrench !

[kramnnim]

Wow...that's some grit. :beer:

[oldpotatoe]

Many got/get all weak kneed about how great this BB was..glad it's gone. I realized that first time I took all the wee bearings out to clean one..geeez, it got dirty and promptly dropped one of the needle bearings, never to be found again..no problem, just call shimano...whatdoyamean, not available!!!

Upgraded many to the far superior 6500 BB...

[AngryScientist]

it's funny that you mention this. i had been eyeing this colnago dream on ebay for a while:

http://www.ebay.com/itm/52cm-Colnago-Dream-Aluminum-Alloy-Frame-Frameset-Road-Bike-Ernesto-Used-Cycling-/111305224160?&_trksid=p2056016.l4276

that frame is aluminum and uses italian threading, and also has a stuck octalink BB. i bet the alu to alu corroded bond is even worse.

[oldpotatoe]

it's funny that you mention this. i had been eyeing this colnago dream on ebay for a while:

http://www.ebay.com/itm/52cm-Colnago-Dream-Aluminum-Alloy-Frame-Frameset-Road-Bike-Ernesto-Used-Cycling-/111305224160?&_trksid=p2056016.l4276

that frame is aluminum and uses italian threading, and also has a stuck octalink BB. i bet the alu to alu corroded bond is even worse.

I'll bet a tool that holds the BB spline tool into the frame, rotate the frame while tool in vice..and it'll come out. Hopefully the guy knows, along with being superior, Italian threading is lefty-loosey...

[carpediemracing]

Not that you now have a sweet tool but putting the tool in a vise and turning the frame is a great trick to know/use. When you start bending frame tubes you know it's really stuck.

Leverage and control is a gazillion times better when using the frame as the lever, not the tool.

[jamesau]

I'll bet a tool that holds the BB spline tool into the frame, rotate the frame while tool in vice..and it'll come out...

... and secure the tool in place with a QR as described on the Park Tool site:
http://www.parktool.com/blog/repair-help/cartridge-bearing-type-bottom-bracket-service-bbt

The track BB-7710 is the Octalink BB to get. It's a cartridge design like the 6500 but uses stainless cups so stronger and presents less of a corrosion issue. And it's still in production.

[guyintense]

Hey Mark, next time that happens you should make one of these.
Granted it will take a little more than a drill press and file but when you're done you can laugh at stuck BB's.

[Anarchist]

I'll bet a tool that holds the BB spline tool into the frame, rotate the frame while tool in vice..and it'll come out. Hopefully the guy knows, along with being superior, Italian threading is lefty-loosey...

^ this.

Clamp the cup faces in a bench vise and rotate the frame.

[11.4]

I've had to work with a horde of Octalink bottom brackets and found that the source of the corrosion (and from an electrogalvanic standpoint there has to be one) is almost always the bolt securing the bottom bracket cable guide. Most people use a bolt that rusts -- even if they choose stainless, it isn't necessarily good stainless (your Ace Hardware stainless bolts aren't the same stainless that you'd get in a high-quality sheave on a racing sailboat). That bolt rusts and the oxide flows to one point on the edge of the alloy and starts eating there.

I found some high-quality nylon bolts and started using them in bottom brackets to secure the cable guide and guess what? ... bottom bracket corrosion stopped. I've also gobbed the inside of that stainless bolt up with anti seize and that's done a pretty good job of preventing it as well.

I agree with Spud about the needle bearings in 7700's. They come in a plastic clip and work fine at first, but as the clip wears, they fall out. You can retrieve them, stick them in with grease, and everything continues to work fine, but if you lose one, you're hosed. It was indeed a great bottom bracket, but it didn't have a long lifetime. On the track, where you can install it and simply not open it for several years, it's simply superb. I'd never ride one on the road.

[bobswire]

Well done, a man after my own heart, Necessity is the mother of invention.

[saf-t]

I found some high-quality nylon bolts and started using them in bottom brackets to secure the cable guide and guess what? ... bottom bracket corrosion stopped.

Neat trick- gonna steal that one!

[oldpotatoe]

I've had to work with a horde of Octalink bottom brackets and found that the source of the corrosion (and from an electrogalvanic standpoint there has to be one) is almost always the bolt securing the bottom bracket cable guide. Most people use a bolt that rusts -- even if they choose stainless, it isn't necessarily good stainless (your Ace Hardware stainless bolts aren't the same stainless that you'd get in a high-quality sheave on a racing sailboat). That bolt rusts and the oxide flows to one point on the edge of the alloy and starts eating there.

I found some high-quality nylon bolts and started using them in bottom brackets to secure the cable guide and guess what? ... bottom bracket corrosion stopped. I've also gobbed the inside of that stainless bolt up with anti seize and that's done a pretty good job of preventing it as well.

I agree with Spud about the needle bearings in 7700's. They come in a plastic clip and work fine at first, but as the clip wears, they fall out. You can retrieve them, stick them in with grease, and everything continues to work fine, but if you lose one, you're hosed. It was indeed a great bottom bracket, but it didn't have a long lifetime. On the track, where you can install it and simply not open it for several years, it's simply superb. I'd never ride one on the road.

Some track guys mention 'lash' with octalink, pushing against both sides of the aluminum notches of the crank.

[ultraman6970]

Mark you did great with the tool, your are really crafty dude.

I been successful using the tool vice technique, the tool - quick release - friend with a hammer technique and what I been using lately is a tool that is similar to the bolt and nuts technique/tool that is moving around, the problem is that it doesnt work with BB as the one you are talking about.

It is so simple, a lot of grease and teflon tape and the threads will be safe from rust forever.

I dot have to agree, since long time ago i was wondering why the cups dont use hexagonal notches, still can't understand how in the world did you cut the metal, that thing was just perfect. Bet you built your own 32 headset tool hehehe :)

[josephr]

thanks to oliver1850 for inspiring this rigging work to remove a Shimano Octolink BB --- since I didn't have a bolt/washer long enough, I got out the bearing press with a box wrench on the BB tool. Did an Old Patatoe no-no and whacked it with hammer --- broke loose with a few good hits.

[miksibis]

i feel so inadequate after reading this post!

the shop guys once made me leave the building before they broke out the cheater bar to remove an old bottom bracket from my landshark. no witnesses!

[pbarry]

Serious tenacity! Big props for the effort and ultimate victory.

[TBDSeattle]

Love the story, and love the photos even more.

We had a cheater bar in the corner of the shop where I was working while an undergrad. We wouldn't use it in front of customers either, as I recall. I was there a couple of years before I learned that I should be clamping the tool and turning the frame.

Oh, and once we cut out a seized aluminum bb from the bb with a dremel tool. It was careful work to cut just the bb cup and not the threads of the bb. I remember sweating a bunch while performing the cuts (had to do 3, so I could tap out the sections one at a time) but it worked perfectly. I don't see myself doing that job again! :eek:

[buldogge]

Nice work Mark…

I have had to stick TWO frames up on the mill so far to remove stuck BBs…both ITA threaded. My Chesini came to me, from France, with a free DA BB…jeez, thanks! My Reus had an older Athena BB…same issue…that one I rode for years until I went to swap UT cups in.

We milled out all the bearings/guts and pulled the spindles and then milled the cups close and chiseled out the remains…have to tread lightly as you get closer to the shell threading.

PITA

-Mark in St. Louis

[ultraman6970]

At least you have tools close to you, the problem is when you have nothing around...

[cderalow]

i replaced the splined square taper shimano on my hybrid recently.

i ended up using my pneumatic impact gun to break it loose.

damn drive side did not want to budge.

[Gummee]

Upgraded many to the far superior 6500 BB...Had one. Realized that it needed re-building and promptly paid the 50g penalty for the 'install it and forget it' Ultegra version

M

[texbike]

The most proper way to handle a 7700 BB is to be extremely careful when removing the BB from the shell, wipe it down gently with a rag once it's removed, and then pitch that cursed piece of crap as far as you possibly can into the nearest large body of water.

What was Shimano thinking on that design????

Texbike

[tumbler]

I found some high-quality nylon bolts and started using them in bottom brackets to secure the cable guide and guess what? ... bottom bracket corrosion stopped.

This sounds interesting. Where did you find the nylon bolts?

[Grant McLean]

What was Shimano thinking on that design????



Pretty sure they were thinking mechanics would use the proper technique.

All you need to do is secure the tool to the splines with a nut that holds the
tool tight against the cup, and it can't slip because the BB axle
holds everything in place. I would recommend that for any tough to
remove cup. Slipping on the edges is the downfall...

I love both the XTR and 7700 octalink BB's. My 1997 mountainbike
is still going strong, have 3 in service on road bikes. They are easily
cleaned and serviced, which is I suppose the reason for the hate,
since people neglect them, and then rant about how they suck.

[Look585]

Pretty sure they were thinking mechanics would use the proper tool (TL-UN96).

That is not the tool needed for a 7700 Bottom Bracket. The 7700 fixed cup and the adjustable cup lockring have a 6 prong design. I believe there is a Shimano tool, but I cannot find the part number. The Park tool version (which is crap) is BBT-7. It should be used very carefully and only with a stack of washers and 15mm bolt threaded into the BB spindle so it doesn't slip and trash the cup/lockring notches.

They spin very well when properly maintained. For me, track use only.

[Grant McLean]

That is not the tool needed for a 7700 Bottom Bracket. The 7700 fixed cup and the adjustable cup lockring have a 6 prong design. I believe there is a Shimano tool, but I cannot find the part number.

Agreed, i realized that after my initial post. With the proper technique
of securing the wrench (something I do on every cup and lockring)
it's really not any issue to remove them.

Of course, the other important factors with (any) aluminum cups are to
1) use a proper anti-seize compound on the threads.
2) turn it the correct direction when trying to remove it!

-g

http://www.bike24.com/i/p/1/4/43941_00_d.jpg

[texbike]

They are easily cleaned and serviced, which is I suppose the reason for the hate, since people neglect them, and then rant about how they suck.

Yep. I'm guilty as charged. My post was only 1/2 in jest. I also have both a XTR and a 7700 Octalink in use currently. However, the 6500 really is better for those of us who prefer the "set it and forget it" option if there is one.

Texbike

[Grant McLean]

Yep. I'm guilty as charged. My post was only 1/2 in jest. I also have both a XTR and a 7700 Octalink in use currently. However, the 6500 really is better for those of us who prefer the "set it and forget it" option if there is one.

Texbike

Agreed. Shimano pretty quickly started offering the 7710 sealed version
(also with a steel fixed cup) after it was clear many people expected to have
the lack of maintenance, and common tools with their other sealed bb's, like
the UN90/91 stuff that the Octalink was replacing.

http://www.bike24.com/i/p/4/3/15934_00_d.jpg

[Tony]

Pretty sure they were thinking mechanics would use the proper technique.

They are easily cleaned and serviced, which is I suppose the reason for the hate, since people neglect them, and then rant about how they suck.

Agree. I think the 7700 BB is a solid, light weight design. Like you've mentioned, easily serviced, just watch out for all those bearing, they tend to hide from you :)
With proper maintenance they will last a very long time. I recently rebuilt two, both spin like new!

[11.4]

As far as 6500's or 7710's, they are both extremely durable bottom brackets. Shimano said that the seals are not as tight on the 7710, but we cut both open and couldn't measure a difference. Resistance from seals and other sources for the two bottom brackets is almost identical.

As for 7700's, I've had ones in track frames that got so old they wore away the white plastic clip that the needle bearings fit into so the bearings started to drop out when opened. I'd just drop them back in place with a dab of grease and everything would reinstall and feel fine. Shimano engineers consistently tell me that the 7700 was their finest bottom bracket ever. But they say that with performance in mind (plus a bit of engineering ego). They agree that it isn't made to last forever, and definitely isn't made to last without regular maintenance.

What this thread is really about is ... there's no such thing as a maintenance free bottom bracket. If the bottom bracket bearings themselves don't go bad, the contact of the bottom bracket cartridge shell and the bottom frame shell will get you. This is where a PF30 bottom bracket with a Delrin adapter starts to make a whole lot more sense.

[oldpotatoe]

As far as 6500's or 7710's, they are both extremely durable bottom brackets. Shimano said that the seals are not as tight on the 7710, but we cut both open and couldn't measure a difference. Resistance from seals and other sources for the two bottom brackets is almost identical.

As for 7700's, I've had ones in track frames that got so old they wore away the white plastic clip that the needle bearings fit into so the bearings started to drop out when opened. I'd just drop them back in place with a dab of grease and everything would reinstall and feel fine. Shimano engineers consistently tell me that the 7700 was their finest bottom bracket ever. But they say that with performance in mind (plus a bit of engineering ego). They agree that it isn't made to last forever, and definitely isn't made to last without regular maintenance.

What this thread is really about is ... there's no such thing as a maintenance free bottom bracket. If the bottom bracket bearings themselves don't go bad, the contact of the bottom bracket cartridge shell and the bottom frame shell will get you. This is where a PF30 bottom bracket with a Delrin adapter starts to make a whole lot more sense.

Really..even if octalink answered no question, solved no problem while adding a few?