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Main
Date: 05 May 2007 22:05:58
From: PJay
Subject: Fitting cartridge BB - how to get it right
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I'm trying to develop a feel for fitting cartridge bottom brackets
(Octalink). Shimano specs. state that both the cartridge and non-driveside
adapter should be torqued to between 50-70Nm.
Is it okay just to go for 'nice and tight' with both flanges up tight
against the BB shell or do I need to be more accurate than this? I
understand that a loose BB could damage the thread in the shell and I don't
want to risk this. Would a BB and/or adapter that were loose enough to cause
thread damage be obvious (creak or wobble) or is it more subtle than that?
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Date: 07 May 2007 07:56:55
From: Michael Warner
Subject: Re: Fitting cartridge BB - how to get it right
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On Sat, 5 May 2007 22:05:58 +0100, PJay wrote:
> I'm trying to develop a feel for fitting cartridge bottom brackets
> (Octalink). Shimano specs. state that both the cartridge and non-driveside
> adapter should be torqued to between 50-70Nm.
>
> Is it okay just to go for 'nice and tight' with both flanges up tight
> against the BB shell or do I need to be more accurate than this? I
> understand that a loose BB could damage the thread in the shell and I don't
> want to risk this. Would a BB and/or adapter that were loose enough to cause
> thread damage be obvious (creak or wobble) or is it more subtle than that?
At such high torque, it's pretty hard to do any damage by using maximum
force (but not jerking) on hand tools of reasonable size - I use a 30cm
wrench for this. I set the body snug against the shell, without tightening
it, then use max force on the lockring, then max force on the
cartridge again. Remember to clean and grease up the threads and
body/lockring interface first, since this gives your torque maximum
effectiveness, and makes disassembly easier later.
--
Home page: http://members.westnet.com.au/mvw
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Date: 07 May 2007 09:16:21
From: PJay
Subject: Re: Fitting cartridge BB - how to get it right
|
Thanks all,
I've used a torque wrench in the past but it's an old second hand one so
quite possibly not that accurate, rather than go blindy by what it says it
feel like a good idea to start to develop a feel for things (not that easy
when you're only working on your own bike - I tend to pop the BB out every 6
months just to regrease the threads, so I don't do a lot of BBs).
I've got a steel frame so I'm careful to ensure that the threads are well
greased. As a bit of a beginner I just need to feel comfortable that I'm not
damaging anything.
It sounds as if a BB that's loose enough to damage the shell threads would
be clearly apparent (creaking and/or wobbling).
Thanks again for the help.
"Michael Warner" <mvw@westnet.com.au > wrote in message
news:sfo3t87pfy9h$.emznop6huei9.dlg@40tude.net...
> On Sat, 5 May 2007 22:05:58 +0100, PJay wrote:
>
>> I'm trying to develop a feel for fitting cartridge bottom brackets
>> (Octalink). Shimano specs. state that both the cartridge and
>> non-driveside
>> adapter should be torqued to between 50-70Nm.
>>
>> Is it okay just to go for 'nice and tight' with both flanges up tight
>> against the BB shell or do I need to be more accurate than this? I
>> understand that a loose BB could damage the thread in the shell and I
>> don't
>> want to risk this. Would a BB and/or adapter that were loose enough to
>> cause
>> thread damage be obvious (creak or wobble) or is it more subtle than
>> that?
>
> At such high torque, it's pretty hard to do any damage by using maximum
> force (but not jerking) on hand tools of reasonable size - I use a 30cm
> wrench for this. I set the body snug against the shell, without tightening
> it, then use max force on the lockring, then max force on the
> cartridge again. Remember to clean and grease up the threads and
> body/lockring interface first, since this gives your torque maximum
> effectiveness, and makes disassembly easier later.
>
>
> --
> Home page: http://members.westnet.com.au/mvw
>
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Date: 06 May 2007 03:48:07
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
PJay wrote:
> I'm trying to develop a feel for fitting cartridge bottom brackets
> (Octalink). Shimano specs. state that both the cartridge and non-driveside
> adapter should be torqued to between 50-70Nm.
>
> Is it okay just to go for 'nice and tight' with both flanges up tight
> against the BB shell or do I need to be more accurate than this? I
> understand that a loose BB could damage the thread in the shell and I don't
> want to risk this. Would a BB and/or adapter that were loose enough to cause
> thread damage be obvious (creak or wobble) or is it more subtle than that?
>
>
Just a suggestion here.
If you are reasonably good at things mechanical you can try to tighten
it yourself and see how it works. Once you hit the point where all
wiggle room disappears only apply a little more torque or you will be
killing your bearings.
If you are unsure of 'anything' then, before riding, figure out what Nm
converts to in foot pounds or something you can walk into an auto store
or LBS and buy the appropriate torque wrench.
Next check how much torque you have applied by your previous best guess
reasoning. You may find yourself dead on or way out in left field.
Remember, any doubts and you take it to a pro.
My 2 cents.
I like working on things when not riding, even if only to find out how
they work.
Best of luck.
Bill Baka
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Date: 07 May 2007 07:58:43
From: Michael Warner
Subject: Re: Fitting cartridge BB - how to get it right
|
On Sun, 06 May 2007 03:48:07 GMT, Bill wrote:
> If you are reasonably good at things mechanical you can try to tighten
> it yourself and see how it works. Once you hit the point where all
> wiggle room disappears only apply a little more torque or you will be
> killing your bearings.
Bill, you don't appear to know what a cartridge is.
--
Home page: http://members.westnet.com.au/mvw
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Date: 06 May 2007 19:24:26
From: DI
Subject: Re: Fitting cartridge BB - how to get it right
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"Michael Warner" <mvw@westnet.com.au > wrote in message
news:ev4onz5bntv2.11afvassgkdf8.dlg@40tude.net...
> On Sun, 06 May 2007 03:48:07 GMT, Bill wrote:
>
>> If you are reasonably good at things mechanical you can try to tighten
>> it yourself and see how it works. Once you hit the point where all
>> wiggle room disappears only apply a little more torque or you will be
>> killing your bearings.
>
> Bill, you don't appear to know what a cartridge is.
>
> --
> Home page: http://members.westnet.com.au/mvw
It appears he's referring to the cheaper *mart type bikes or BMX bikes with
one piece cranks and attempting to explain how to preload the bearings.
Not doing a very good job at that.
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Date: 07 May 2007 01:08:20
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
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DI wrote:
> "Michael Warner" <mvw@westnet.com.au> wrote in message
> news:ev4onz5bntv2.11afvassgkdf8.dlg@40tude.net...
>> On Sun, 06 May 2007 03:48:07 GMT, Bill wrote:
>>
>>> If you are reasonably good at things mechanical you can try to tighten
>>> it yourself and see how it works. Once you hit the point where all
>>> wiggle room disappears only apply a little more torque or you will be
>>> killing your bearings.
>> Bill, you don't appear to know what a cartridge is.
>>
>> --
>> Home page: http://members.westnet.com.au/mvw
>
> It appears he's referring to the cheaper *mart type bikes or BMX bikes with
> one piece cranks and attempting to explain how to preload the bearings.
> Not doing a very good job at that.
>
>
Not a chance on that. I won't even take one of those for free. All my
mountain bikes have removable cranks with square holes. I even have both
large and small shell types. Whatever you guys do may be different than
the way I do it, but my bottom brackets have gotten a little loose and I
have tightened them 'just enough'. I learned to check after losing all
the bearings from the Huffy and having to walk home and then drive the
bike to the LBS. $20 something later and I was riding again, with a much
better bottom bracket. None of this is rocket science so I figure that
if somebody takes one apart they should be able to put it back together
again. Just reverse the sequence. I have a torque wrench for the car but
it goes to 150 foot pounds so it is vast overkill for anything bike.
Bill Baka
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Date: 07 May 2007 13:54:14
From: Antti Salonen
Subject: Re: Fitting cartridge BB - how to get it right
|
Bill <bbaka@comcast.net > wrote:
> Whatever you guys do may be different than
> the way I do it, but my bottom brackets have gotten a little loose and I
> have tightened them 'just enough'. I learned to check after losing all
> the bearings from the Huffy and having to walk home and then drive the
> bike to the LBS. $20 something later and I was riding again, with a much
> better bottom bracket. None of this is rocket science so I figure that
> if somebody takes one apart they should be able to put it back together
> again. Just reverse the sequence. I have a torque wrench for the car but
> it goes to 150 foot pounds so it is vast overkill for anything bike.
Well the range given in the Shimano instructions is about 40 to 50 foot
pounds, so your torque wrench sounds like a proper tool for the job.
The point is that 50 to 70 Nm is a lot of torque - much more than "just
enough". With a cartridge bottom bracket more torque doesn't damage the
bearings as long as the threads in the bottom bracket shell are straight.
Antti
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Date: 07 May 2007 07:49:32
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
Antti Salonen wrote:
> Bill <bbaka@comcast.net> wrote:
>
>> Whatever you guys do may be different than
>> the way I do it, but my bottom brackets have gotten a little loose and I
>> have tightened them 'just enough'. I learned to check after losing all
>> the bearings from the Huffy and having to walk home and then drive the
>> bike to the LBS. $20 something later and I was riding again, with a much
>> better bottom bracket. None of this is rocket science so I figure that
>> if somebody takes one apart they should be able to put it back together
>> again. Just reverse the sequence. I have a torque wrench for the car but
>> it goes to 150 foot pounds so it is vast overkill for anything bike.
>
> Well the range given in the Shimano instructions is about 40 to 50 foot
> pounds, so your torque wrench sounds like a proper tool for the job.
>
> The point is that 50 to 70 Nm is a lot of torque - much more than "just
> enough". With a cartridge bottom bracket more torque doesn't damage the
> bearings as long as the threads in the bottom bracket shell are straight.
>
> Antti
Hmmmm,
I was basing my response on things like car front wheel bearings 'and'
bottom brackets and 40-50 foot pounds seems a bit tight.
But, hey, I don't know how each manufacturer does it. That amount of
torque should only be for a secondary lock nut if I am correct.
I would never dream of tightening my car's wheel bearings that tight.
Bill Baka
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Date: 07 May 2007 10:46:01
From: DI
Subject: Re: Fitting cartridge BB - how to get it right
|
"Bill" <bbaka@comcast.net > wrote in message
news:V%G%h.1440$SC4.960@nlpi068.nbdc.sbc.com...
> Antti Salonen wrote:
>> Bill <bbaka@comcast.net> wrote:
>>
>>> Whatever you guys do may be different than the way I do it, but my
>>> bottom brackets have gotten a little loose and I have tightened them
>>> 'just enough'. I learned to check after losing all the bearings from the
>>> Huffy and having to walk home and then drive the bike to the LBS. $20
>>> something later and I was riding again, with a much better bottom
>>> bracket. None of this is rocket science so I figure that if somebody
>>> takes one apart they should be able to put it back together again. Just
>>> reverse the sequence. I have a torque wrench for the car but it goes to
>>> 150 foot pounds so it is vast overkill for anything bike.
>>
>> Well the range given in the Shimano instructions is about 40 to 50 foot
>> pounds, so your torque wrench sounds like a proper tool for the job.
>>
>> The point is that 50 to 70 Nm is a lot of torque - much more than "just
>> enough". With a cartridge bottom bracket more torque doesn't damage the
>> bearings as long as the threads in the bottom bracket shell are straight.
>>
>> Antti
>
> Hmmmm,
> I was basing my response on things like car front wheel bearings 'and'
> bottom brackets and 40-50 foot pounds seems a bit tight.
> But, hey, I don't know how each manufacturer does it. That amount of
> torque should only be for a secondary lock nut if I am correct.
> I would never dream of tightening my car's wheel bearings that tight.
> Bill Baka
Bill, why don't you admit you don't have the slightest idea what you are
talking about and save some face. You're just getting in deeper,
preloading the taper roller bearing like what's used on car wheels is
entirely different than ball bearings of a bicycle bottom bracket where the
nut has no relation to the bearing itself. BTW, there is no secondary
locknut.
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Date: 07 May 2007 17:54:10
From: T. Ling Yu
Subject: Re: Fitting cartridge BB - how to get it right
|
"DI" <di9999@cox.net > wrote in news:_QH%h.63277$Fk2.52000@newsfe08.phx:
>
> "Bill" <bbaka@comcast.net> wrote in message
> news:V%G%h.1440$SC4.960@nlpi068.nbdc.sbc.com...
>> Antti Salonen wrote:
>>> Bill <bbaka@comcast.net> wrote:
>>>
>>>> Whatever you guys do may be different than the way I do it, but my
>>>> bottom brackets have gotten a little loose and I have tightened
>>>> them 'just enough'. I learned to check after losing all the
>>>> bearings from the Huffy and having to walk home and then drive the
>>>> bike to the LBS. $20 something later and I was riding again, with a
>>>> much better bottom bracket. None of this is rocket science so I
>>>> figure that if somebody takes one apart they should be able to put
>>>> it back together again. Just reverse the sequence. I have a torque
>>>> wrench for the car but it goes to 150 foot pounds so it is vast
>>>> overkill for anything bike.
>>>
>>> Well the range given in the Shimano instructions is about 40 to 50
>>> foot pounds, so your torque wrench sounds like a proper tool for the
>>> job.
>>>
>>> The point is that 50 to 70 Nm is a lot of torque - much more than
>>> "just enough". With a cartridge bottom bracket more torque doesn't
>>> damage the bearings as long as the threads in the bottom bracket
>>> shell are straight.
>>>
>>> Antti
>>
>> Hmmmm,
>> I was basing my response on things like car front wheel bearings
>> 'and' bottom brackets and 40-50 foot pounds seems a bit tight.
>> But, hey, I don't know how each manufacturer does it. That amount of
>> torque should only be for a secondary lock nut if I am correct.
>> I would never dream of tightening my car's wheel bearings that tight.
>> Bill Baka
>
> Bill, why don't you admit you don't have the slightest idea what you
> are talking about and save some face. You're just getting in
> deeper, preloading the taper roller bearing like what's used on car
> wheels is entirely different than ball bearings of a bicycle bottom
> bracket where the nut has no relation to the bearing itself. BTW,
> there is no secondary locknut.
>
Bill just realizes that cartridge tightening is too simple a
topic for him to adequately display his expertise, so he steers the
discussion towards proper tightening of cup-and-cone bearings
so that we may be suitably impressed with not only his bicycle
accumen, but also his automotive knowledge.
Bill is a modern day Renaissance Man. All he needs are the
colorful tights, but lycra can do in a pinch.
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Date: 06 May 2007 22:31:17
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
Michael Warner wrote:
> On Sun, 06 May 2007 03:48:07 GMT, Bill wrote:
>
>> If you are reasonably good at things mechanical you can try to tighten
>> it yourself and see how it works. Once you hit the point where all
>> wiggle room disappears only apply a little more torque or you will be
>> killing your bearings.
>
> Bill, you don't appear to know what a cartridge is.
>
Pointer?
That was mostly general info for a beginning wrench artist.
Bill Baka
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Date: 07 May 2007 08:22:29
From: Michael Warner
Subject: Re: Fitting cartridge BB - how to get it right
|
On Sun, 06 May 2007 22:31:17 GMT, Bill wrote:
> That was mostly general info for a beginning wrench artist.
As opposed to a useful answer to the question.
Even though you may have completely misled the OP, I'm
sure he's gone away in awe of your mechanical skills, and
that's the important thing, isn't it?
--
Home page: http://members.westnet.com.au/mvw
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Date: 06 May 2007 22:55:51
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
Michael Warner wrote:
> On Sun, 06 May 2007 22:31:17 GMT, Bill wrote:
>
>> That was mostly general info for a beginning wrench artist.
>
> As opposed to a useful answer to the question.
>
> Even though you may have completely misled the OP, I'm
> sure he's gone away in awe of your mechanical skills, and
> that's the important thing, isn't it?
>
Not really.
I can rebuild an automatic transmission pretty well though.
Bill
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Date: 07 May 2007 00:09:55
From: T. Ling Yu
Subject: Re: Fitting cartridge BB - how to get it right
|
Bill <bbaka@comcast.net > wrote in news:X1t%h.7503$rO7.20
@newssvr25.news.prodigy.net:
> Michael Warner wrote:
>> On Sun, 06 May 2007 22:31:17 GMT, Bill wrote:
>>
>>> That was mostly general info for a beginning wrench artist.
>>
>> As opposed to a useful answer to the question.
>>
>> Even though you may have completely misled the OP, I'm
>> sure he's gone away in awe of your mechanical skills, and
>> that's the important thing, isn't it?
>>
> Not really.
> I can rebuild an automatic transmission pretty well though.
Without a smiley, it's hard to tell if you're trying to
be ironic. :)
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Date: 06 May 2007 18:00:45
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
T. Ling Yu wrote:
> Bill <bbaka@comcast.net> wrote in news:X1t%h.7503$rO7.20
> @newssvr25.news.prodigy.net:
>
>> Michael Warner wrote:
>>> On Sun, 06 May 2007 22:31:17 GMT, Bill wrote:
>>>
>>>> That was mostly general info for a beginning wrench artist.
>>> As opposed to a useful answer to the question.
>>>
>>> Even though you may have completely misled the OP, I'm
>>> sure he's gone away in awe of your mechanical skills, and
>>> that's the important thing, isn't it?
>>>
>> Not really.
>> I can rebuild an automatic transmission pretty well though.
>
> Without a smiley, it's hard to tell if you're trying to
> be ironic. :)
>
No smiley's from me since they are not enabled, but it is true.
I used to rebuild racing type trannies for me and few friends.
Same goes for my car's engine. I started when I was 16 and my first car
was a Buick with a Dyna-slow transmission and a straight 8. 2 weeks
after I got the car reverse went out so I dove in and learned.
Doing it yourself is ever so much better than trying to learn from a book.
I'm a hopeless do it yourself'er.
Bill Baka
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Date: 06 May 2007 18:17:05
From: Bill Sornson
Subject: Re: Fitting cartridge BB - how to get it right
|
Bill wrote:
> No smiley's from me since they are not enabled
ROTFL LOL ROTFL
:-D :-P <eg > :o) 8-) 8-O
Good stuff, MENSA! ;-)
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Date: 07 May 2007 01:27:54
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
Bill Sornson wrote:
> Bill wrote:
>
>> No smiley's from me since they are not enabled
>
> ROTFL LOL ROTFL
>
> :-D :-P <eg> :o) 8-) 8-O
>
> Good stuff, MENSA! ;-)
>
>
Sore Knee,
I just don't use them much because as I am writing this your smileys
just turned into basic characters. ;<)
It takes long enough to get through this group as is.
:-D :-P <eg > :o) 8-) 8-O
Bye now.
Bill Baka
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Date: 06 May 2007 19:34:09
From: Bill Sornson
Subject: Re: Fitting cartridge BB - how to get it right
|
Bill wrote:
> Bill Sornson wrote:
>> Bill wrote:
>>
>>> No smiley's from me since they are not enabled
>>
>> ROTFL LOL ROTFL
>>
>> :-D :-P <eg> :o) 8-) 8-O
>>
>> Good stuff, MENSA! ;-)
>>
>>
> Sore Knee,
> I just don't use them much because as I am writing this your smileys
> just turned into basic characters. ;<)
> It takes long enough to get through this group as is.
> :-D :-P <eg> :o) 8-) 8-O
> Bye now.
> Bill Baka
You wrote that they're not "enabled", not that you don't use them. (Sort of
like you wrote long ago that you couldn't block individual posters.)
Rather strange for a brilliant computer expert like you.
Out.
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Date: 07 May 2007 08:32:51
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
Bill Sornson wrote:
> Bill wrote:
>> Bill Sornson wrote:
>>> Bill wrote:
>>>
>>>> No smiley's from me since they are not enabled
>>> ROTFL LOL ROTFL
>>>
>>> :-D :-P <eg> :o) 8-) 8-O
>>>
>>> Good stuff, MENSA! ;-)
>>>
>>>
>> Sore Knee,
>> I just don't use them much because as I am writing this your smileys
>> just turned into basic characters. ;<)
>> It takes long enough to get through this group as is.
>> :-D :-P <eg> :o) 8-) 8-O
>> Bye now.
>> Bill Baka
>
> You wrote that they're not "enabled", not that you don't use them. (Sort of
> like you wrote long ago that you couldn't block individual posters.)
>
> Rather strange for a brilliant computer expert like you.
>
> Out.
>
>
I'm using Thunderbird and it won't block people in the news groups.
I just searched and there is not even an option for smileys.
Sorry, but that's the way Thunderbird does things.
Bill Baka
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Date: 07 May 2007 09:27:52
From: Bill Sornson
Subject: Re: Fitting cartridge BB - how to get it right
|
Bill wrote:
> Bill Sornson wrote:
>> Bill wrote:
>>> Bill Sornson wrote:
>>>> Bill wrote:
>>>>
>>>>> No smiley's from me since they are not enabled
>>>> ROTFL LOL ROTFL
>>>>
>>>> :-D :-P <eg> :o) 8-) 8-O
>>>>
>>>> Good stuff, MENSA! ;-)
>>>>
>>>>
>>> Sore Knee,
>>> I just don't use them much because as I am writing this your smileys
>>> just turned into basic characters. ;<)
>>> It takes long enough to get through this group as is.
>>> :-D :-P <eg> :o) 8-) 8-O
>>> Bye now.
>>> Bill Baka
>>
>> You wrote that they're not "enabled", not that you don't use them. (Sort
>> of like you wrote long ago that you couldn't block individual
>> posters.) Rather strange for a brilliant computer expert like you.
>>
>> Out.
>>
>>
> I'm using Thunderbird and it won't block people in the news groups.
> I just searched and there is not even an option for smileys.
> Sorry, but that's the way Thunderbird does things.
Last comment: :) or ;-) or whatever are called "emoticons" -- people see
the /symbols/ and know what they mean. This only applies to conscious
people, however, so that obviously leaves you out.
<eg > !
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Date: 06 May 2007 21:13:40
From: PJay
Subject: Re: Fitting cartridge BB - how to get it right
|
Thanks,
I've used a torque wrench in the past but when I mention it I'm often told
that you don't need a toruqe wrench or that I should learn to develop a
'feel'. Most of the maintenance books I've read just tend to suggest that it
needs to be done up tight. Shimano give a torque range of 50-70Nm which is
fairly wide.
I guess that my main concern is getting it too loose so that it could damage
the shell threads. Would a BB that was loose enough to do this be obvious
(wobbly and/or creaking)?
Thanks for taking the time to reply :-)
"Bill" <bbaka@comcast.net > wrote in message
news:Xdc%h.16826$YL5.3379@newssvr29.news.prodigy.net...
> PJay wrote:
>> I'm trying to develop a feel for fitting cartridge bottom brackets
>> (Octalink). Shimano specs. state that both the cartridge and
>> non-driveside adapter should be torqued to between 50-70Nm.
>>
>> Is it okay just to go for 'nice and tight' with both flanges up tight
>> against the BB shell or do I need to be more accurate than this? I
>> understand that a loose BB could damage the thread in the shell and I
>> don't want to risk this. Would a BB and/or adapter that were loose enough
>> to cause thread damage be obvious (creak or wobble) or is it more subtle
>> than that?
> Just a suggestion here.
> If you are reasonably good at things mechanical you can try to tighten it
> yourself and see how it works. Once you hit the point where all wiggle
> room disappears only apply a little more torque or you will be killing
> your bearings.
> If you are unsure of 'anything' then, before riding, figure out what Nm
> converts to in foot pounds or something you can walk into an auto store or
> LBS and buy the appropriate torque wrench.
> Next check how much torque you have applied by your previous best guess
> reasoning. You may find yourself dead on or way out in left field.
> Remember, any doubts and you take it to a pro.
> My 2 cents.
> I like working on things when not riding, even if only to find out how
> they work.
> Best of luck.
> Bill Baka
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Date: 07 May 2007 08:01:01
From: Michael Warner
Subject: Re: Fitting cartridge BB - how to get it right
|
On Sun, 6 May 2007 21:13:40 +0100, PJay wrote:
> I guess that my main concern is getting it too loose so that it could damage
> the shell threads. Would a BB that was loose enough to do this be obvious
> (wobbly and/or creaking)?
When a BB starts to loosen, it creaks when you apply extra force (i.e.
standing on the pedals). If you let it get bad, you'll be able to feel it
shift under the pressure, by which time it may well be doing
and/or suffering some damage.
--
Home page: http://members.westnet.com.au/mvw
|
| | | |
Date: 06 May 2007 20:57:09
From: Bill
Subject: Re: Fitting cartridge BB - how to get it right
|
PJay wrote:
> Thanks,
>
> I've used a torque wrench in the past but when I mention it I'm often told
> that you don't need a toruqe wrench or that I should learn to develop a
> 'feel'. Most of the maintenance books I've read just tend to suggest that it
> needs to be done up tight. Shimano give a torque range of 50-70Nm which is
> fairly wide.
Yes, but do you have a calibrated feel?
>
> I guess that my main concern is getting it too loose so that it could damage
> the shell threads. Would a BB that was loose enough to do this be obvious
> (wobbly and/or creaking)?
I would think (no guarantees) that you would notice it well before
damage was done. I give the cranks a test before I ride. It's kind of
simple but effective. If you can grab both pedals and feel **any**
wiggle then you need to tighten things a bit. If the crank is hard to
turn then you need to loosen a bit. Eventually (I hope) you will develop
that 'feel'.
Bill Baka
>
> Thanks for taking the time to reply :-)
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