Shimano DuraAce 7700 Octalink BB races
Ronko
Bottom Brackets and both have pitted bearing races on the spindle.
The races will pop out. Are these still available, what would be the
part number, and hopefully not at some ridiculous price.
thanks!
Ronko
ronkr...@gmail.com says...
1TG 07000
bfd
> In article <i7j1p5$je...@news.eternal-september.org>,
> ronkreu...@gmail.com says...
>
> >Ok, here's a real stab in the dark. I have two of the 7700 DuraAce
> >Bottom Brackets and both have pitted bearing races on the spindle.
> >The races will pop out. Are these still available, what would be the
> >part number, and hopefully not at some ridiculous price.
>
> >thanks!
>
> As a quick followup to my initial post, Shimano calls it a "cone" part #: Y-
> 1TG 07000
Talk to an LBS and have them check with Shimano. The problem is the bb
has been discontinued and is no longer available. Further, the fact
that you actually found a part number helps, but that doesn't
necessarily mean anything as Shimano is not very good with supplying
small parts. Otherwise, go look for another on ebay or one of the
euro bike shops. Good Luck!
Ronko
0cd262...@x18g2000pro.googlegroups.com>, bfd...@gmail.com
says...
Jay Beattie
> In article <cbdbba80-1c68-42e9-ab67-
> 0cd2621cb...@x18g2000pro.googlegroups.com>, bfd...@gmail.com
>
> - Show quoted text -
BTW, even if you can find races, you will end up with a BB that was
worse than the 105 grade BB. My friends who owned those cranks were
very critical of the BBs in PNW wet conditions and switched to the
cheaper BB. I would not waste my time and money trying to fix the old
one and would buy a cheap replacement, particularly since you will
want to upgrade to an all new, incompatible system soon enough. And if
you wait long enough, it will be incompatible system 1.1, whatever
that might be. Perhaps a one piece crank that slips in through a trap
door in the BB. -- Jay Beattie.
Jobst Brandt
> OK, here's a real stab in the dark. I have two of the 7700 DuraAce
> Bottom Brackets and both have pitted bearing races on the spindle.
> The races will pop out. Are these still available, what would be
> the part number, and hopefully not at some ridiculous price.
A good reason why Shimano discontinued this system is that the eight
fluted spline is not a press fit, and therefore, has actual and
elastic backlash that develops greater rotational clearance
(backlash) in use.
I think this may be where Shimano discovered how to mesh
steel-to-aluminum splines as in the Hollow-tech system. This problem
exists in various bicycle parts including the pedal-to-crank
interface. The left hand thread on left pedals serves only to prevent
unscrewing, but it does not prevent plastic erosion of the aluminum
crank, often leading to pedal eye break-outs.
Jobst Brandt
Ronko
42c6c5...@q16g2000prf.googlegroups.com>, jbea...@lindsayhart.com
says...
shining hour in terms of design. Although about 40-50g lighter than the
Ultegra 6500 octalink BB, this 7700 BB is not sealed well, requires finicky
adjustment after installation, and because of the bad seals require
reinstallation with any significant use. Anectodally I have heard when
teams at the Tour de France were using these, the mechanics got tired of
reinstalling and readjusting frequently and replaced these with the Ultegra
sealed octalink. I'm just looking for the cones as preparation to selling them
in good working order to those who still think highly of these.
thirty-six
No it doesn't!
>
> Jobst Brandt
thirty-six
> you wait long enough, it will be incompatible system 1.1, whatever
> that might be. Perhaps a one piece crank that slips in through a trap
> door in the BB. -- Jay Beattie.
Any sketches yet? A unit crank assembly seems like a good idea, as
was the helicomatic freewheel. At least as a unit system, you can
play about to your hearts content with bearing size, ]
placement and sealing etc.
Jobst Brandt
> No it doesn't!
Who is "it"? I broke at least one crank per year for about 30 years
until I modified the pedal attachment to simulate what cars did with
the conical faced lug nut that got rid of their left hand thread and
wheel stud failures. Beside that there was a thread here about
threads and their function and clearances that you may have missed.
Jobst Brandt
m-gineering
>>> As a quick followup to my initial post, Shimano calls it a "cone" part #:
> Y-
>>> 1TG 07000
>>
>> Talk to an LBS and have them check with Shimano. The problem is the bb
>> has been discontinued and is no longer available.
It still continues in the track groupset
Further, the fact
>> that you actually found a part number helps, but that doesn't
>> necessarily mean anything as Shimano is not very good with supplying
>> small parts. Otherwise, go look for another on ebay or one of the
>> euro bike shops. Good Luck!
> Which specific euro bike shops are your referring to? Thanks.
>
Shimano Europe lists it, it should retail for 25-30 euro's!
--
/Marten
info(apestaartje)m-gineering(punt)nl
Barry
>>> serves only to prevent unscrewing, but it does not prevent plastic
>>> erosion of the aluminum crank, often leading to pedal eye
>>> break-outs.
>
>> No it doesn't!
>
> Who is "it"? I broke at least one crank per year for about 30 years
> until I modified the pedal attachment to simulate what cars did with
> the conical faced lug nut that got rid of their left hand thread and
> wheel stud failures.
What is "often" in this context? Do modern (but unmodified) cranks still fail
like this? How often do others (especially the shop owners and full-time
mechanics) see this type of failure?
Jay Beattie
They still break, but not at the pedal eye -- or at least not in the
same way at the pedal eye. I cracked a threaded insert at the pedal
eye in a CF crank, but it did not migrate in to the surrounding
material. It was just a crappy insert in a now-discontinued FSA ISIS
crank (which in itself was a failure). Every "modern" crank failure
I have had has been above the pedal eye -- by quite some margin.
See http://www.yellowjersey.org/jayscranks.html -- Jay
Beattie.
Jobst Brandt
>>>>> The left hand thread on left pedals serves only to prevent
>>>>> unscrewing, but it does not prevent plastic erosion of the
>>>>> aluminum crank, often leading to pedal eye break-outs.
>>>> No it doesn't!
>>> Who is "it"? I broke at least one crank per year for about 30
>>> years until I modified the pedal attachment to simulate what cars
>>> did with the conical faced lug nut that got rid of their left hand
>>> thread and wheel stud failures.
>> What is "often" in this context? Do modern (but unmodified) cranks
>> still fail like this? How often do others (especially the shop
>> owners and full-time mechanics) see this type of failure?
Sorry, I meant aluminum cranks, both solid and hollow tech.
> They still break, but not at the pedal eye -- or at least not in the
> same way at the pedal eye. I cracked a threaded insert at the pedal
> eye in a CF crank, but it did not migrate in to the surrounding
> material. It was just a crappy insert in a now-discontinued FSA ISIS
> crank (which in itself was a failure). Every "modern" crank failure
> I have had has been above the pedal eye -- by quite some margin.
> See:
http://www.yellowjersey.org/jayscranks.html
I've got the remains of a pair of those, but that's Hollowtech with a
built in crack generator at the sharp ends of the void (fore and aft).
If they last longer, the pedal eye goes next, the pedal attchment
being the same as "solid tech".
Jobst Brandt
kolldata
>
> - Show quoted text -
THAT'S because you never change your spokes
kolldata
unitized BB from Nashbar for $3.98 with free shipping are 10x better
than ball and cone.
thirty-six
> Who is "it"? I broke at least one crank per year for about 30 years
> until I modified the pedal attachment to simulate what cars did with
There was no inducement for you to make changes because the breakages
carried little risk to you personally and the replacements were made
at no cost to you.
So what pedals? What fastening torque? Why weren't you using
Stronglight or TA instead of lightweight racing cranks?
A deep chamfer on the crank thread is sufficient to remove thread
stresses from the crank surface and so protect from crack formation.
You fancy solution is overty extravagent and irrelevant to modern
metal racing cranks and pedals.
Jobst Brandt
>> Who is "it"? I broke at least one crank per year for about 30 years
>> until I modified the pedal attachment to simulate what cars did with
> There was no inducement for you to make changes because the breakages
> carried little risk to you personally and the replacements were made
> at no cost to you.
Neither is correct. I paid to have the colletts made and the cranks
to be countersunk. Beside that, starting a traffic light controlled
crossing was a standing start next to, at times, heavy trucks. If a
left crank broke once I got some speed on, I would fall under the
dual tires of the adjacent truck (possibly a loaded ready -mix truck).
That is a fatal hazard to me and others with such cranks.
> So what pedals? What fastening torque? Why weren't you using
> Stronglight or TA instead of lightweight racing cranks?
Dura Ace solid cranks are as thick as any at the pedal eye. What do
you have in mind?
http://www.chiark.greenend.org.uk/~damerell/bikes/brandt-cranks.jpg
>> the conical faced lug nut that got rid of their left hand thread and
>> wheel stud failures. Beside that there was a thread here about
>> threads and their function and clearances that you may have missed.
> A deep chamfer on the crank thread is sufficient to remove thread
> stresses from the crank surface and so protect from crack formation.
> You fancy solution is overty extravagent and irrelevant to modern
> metal racing cranks and pedals.
If the pedal spindle is flat faced, it will wear cracks into the crank
face. As I said, cars switched to conical lug nuts to get rid of the
motion at the interface.
Jobst Brandt
thirty-six
> Trevor Jeffrey wrote:
> >> Who is "it"? I broke at least one crank per year for about 30 years
> >> until I modified the pedal attachment to simulate what cars did with
> > There was no inducement for you to make changes because the breakages
> > carried little risk to you personally and the replacements were made
> > at no cost to you.
>
> Neither is correct. I paid to have the colletts made and the cranks
Irrelevant to the cranks you repeatedly broke which were replaced free
of charge to you.
> to be countersunk. Beside that, starting a traffic light controlled
> crossing was a standing start next to, at times, heavy trucks. If a
> left crank broke once I got some speed on, I would fall under the
> dual tires of the adjacent truck (possibly a loaded ready -mix truck).
> That is a fatal hazard to me and others with such cranks.
>
> > So what pedals? What fastening torque? Why weren't you using
> > Stronglight or TA instead of lightweight racing cranks?
>
> Dura Ace solid cranks are as thick as any at the pedal eye. What do
> you have in mind?
You didn't break dura-ace cranks, your modification is a superfluous
affectation.
You free cranks were Campag's.
I'll ask again, what pedals were you using with these cranks you kept
breaking?
What was the fastening torque?
>
> http://www.chiark.greenend.org.uk/~damerell/bikes/brandt-cranks.jpg
>
> >> the conical faced lug nut that got rid of their left hand thread and
> >> wheel stud failures. Beside that there was a thread here about
> >> threads and their function and clearances that you may have missed.
> > A deep chamfer on the crank thread is sufficient to remove thread
> > stresses from the crank surface and so protect from crack formation.
> > You fancy solution is overty extravagent and irrelevant to modern
> > metal racing cranks and pedals.
>
> If the pedal spindle is flat faced,
Modern racing pedals have a small radius so the boss is not entirely
flat.
> it will wear cracks into the crank
They dont.
> face. As I said, cars switched to conical lug nuts to get rid of the
> motion at the interface.
Irrelevance.
>
> Jobst Brandt
Tim McNamara
Jobst Brandt <jbr...@sonic.net> wrote:
Some samples here, if this has not already been referenced:
http://pardo.net/bike/pic/fail-001/000.html
--
That'll put marzipan in your pie plate, Bingo.
Jay Beattie
> In article <4ca12033$0$1588$742ec...@news.sonic.net>,
I broke a bunch of NR cranks, too (among others) -- but always above
the pedal eye. I don't think I ever had a true pedal-eye failure, at
least not of the type shown in some of those pictures. It does seem
that using a conical attachment would be a pretty easy thing to do,
and with all the proprietary parts these days, money could be made
with a pedal/crank/BB "system." Maybe a BB30 or something exotic with
CF or CF graphics (some contact paper or silk screen). -- Jay Beattie.
Jobst Brandt
>>>>>>>> The left hand thread on left pedals serves only to prevent
>>>>>>>> unscrewing, but it does not prevent plastic erosion of the
>>>>>>>> aluminum crank, often leading to pedal eye break-outs.
>>>>>>> No it doesn't!
>>>>>> Who is "it"? I broke at least one crank per year for about 30
>>>>>> years until I modified the pedal attachment to simulate what
>>>>>> cars did with the conical faced lug nut that got rid of their
>>>>>> left hand thread and wheel stud failures.
>>>>> What is "often" in this context? Do modern (but unmodified)
>>>>> cranks still fail like this? How often do others (especially
>>>>> the shop owners and full-time mechanics) see this type of
>>>>> failure?
>>> Sorry, I meant aluminum cranks, both solid and hollow tech.
>>>> They still break, but not at the pedal eye -- or at least not in
>>>> the same way at the pedal eye. I cracked a threaded insert at
>>>> the pedal eye in a CF crank, but it did not migrate in to the
>>>> surrounding material. It was just a crappy insert in a
>>>> now-discontinued FSA ISIS crank (which in itself was a failure).
>>>> Every "modern" crank failure I have had has been above the pedal
>>>> eye -- by quite some margin. See:
http://www.yellowjersey.org/jayscranks.html
http://www.yellowjersey.org/photosfromthepast/yesdeydo.jpg
>>> I've got the remains of a pair of those, but that's Hollowtech
>>> with a built in crack generator at the sharp ends of the void
>>> (fore and aft). If they last longer, the pedal eye goes next, the
>>> pedal attachment being the same as "solid tech".
>> Some samples here, if this has not already been referenced:
http://pardo.net/bike/pic/fail-001/000.html
> I broke a bunch of NR cranks, too (among others) -- but always above
> the pedal eye. I don't think I ever had a true pedal-eye failure,
> at least not of the type shown in some of those pictures. It does
> seem that using a conical attachment would be a pretty easy thing to
> do, and with all the proprietary parts these days, money could be
> made with a pedal/crank/BB "system." Maybe a BB30 or something
> exotic with CF or CF graphics (some contact paper or silk screen).
This is not something that will come along soon. I've spent a few
years at InterBike showing a cracked (but un-separated) crank and a
modified countersunk pedal-to-crank assembly to various manufacturers,
including senior Japanese Shimano managers, all of whom expressed
disbelief in the occurrence of such a failure and that the conical
face would affect it.
This response may be brought on by the fear that any change would be
proof for damage claims by users. That seems absurd to me but the
tone of some of these folks was in that vein.
Jobst Brandt
Tim McNamara
<a667a18f-a165-417e...@q16g2000prf.googlegroups.com>,
Jay Beattie <jbea...@lindsayhart.com> wrote:
> I broke a bunch of NR cranks, too (among others) -- but always above
> the pedal eye. I don't think I ever had a true pedal-eye failure, at
> least not of the type shown in some of those pictures. It does seem
> that using a conical attachment would be a pretty easy thing to do,
> and with all the proprietary parts these days, money could be made
> with a pedal/crank/BB "system." Maybe a BB30 or something exotic with
> CF or CF graphics (some contact paper or silk screen). -- Jay Beattie.
"TCA Technology" stickers on the cranks in garish colors.
thirty-six
> This is not something that will come along soon. I've spent a few
> years at InterBike showing a cracked (but un-separated) crank and a
> modified countersunk pedal-to-crank assembly to various manufacturers,
> including senior Japanese Shimano managers, all of whom expressed
> disbelief in the occurrence of such a failure and that the conical
> face would affect it.
It doesn't happen when good pedals are matched to good cranks and
assembled with the appropriate procedure. Oil the threads and stand
(rider's weight) on the pedal spanner to get the correct torque.
>
> This response may be brought on by the fear that any change would be
> proof for damage claims by users. That seems absurd to me but the
> tone of some of these folks was in that vein.
Certainly. If correct procedure is followed then failures do not
occur. Why should they change a proven system for the inept mechanic?
I'll ask again, what pedals were you using with these cranks you kept
destroying?
DirtRoadie
Apparently you missed the part at:
http://pardo.net/bike/pic/fail-001/FAIL-001.html
that says
"Pedal eye failures seem ominous but not some decisive majority.
Fixing that so that cranks last long enough to break elsewhere,
catastrophically of course, is possibly misspent. "
DR