Stripped crank arms = replace Tiagra cranks with 105 or Ultegra, new BB needed?



On 2006-01-31, [email protected] <[email protected]> wrote:

> Leo Lichtman wrote:


>> All true. A Helicoil is tougher and more durable than any aluminum thread.


> How can the Helicoil be better than or more durable than the original
> crank threading? Doesn't the Helicoil thread into the aluminum crank
> itself? Therefore, at best, at best, it can only be as durable as the
> original, not better than new or more durable.


Ah, but it's a larger diameter than the original, so the stresses are
spread over a larger area.

--

John ([email protected])
 
"Jeff Starr" <[email protected]> wrote in message
news:p[email protected]...
> On Wed, 01 Feb 2006 05:45:51 GMT, "Leo Lichtman"
> <[email protected]> wrote:
>
>>
>>"Brad Ford" I've had ulterior motives in taking the pedals off every 6
>>weeks. (clip)
>>^^^^^^^^^^^^^^^^
>>Go back to Recyclery and look in the room up front. They have BOXES of
>>used
>>pedals for very reasonable prices. You could probably find a pretty good
>>pair to save yourself a lot of work, wear and tear.
>>
>>And, YES! Aren't they great people to deal with? On top of that, the
>>money
>>you spend there goes to a very worthwhile cause. They take inner city
>>kids
>>for mountain bike rides. They also train kids to repair bikes, and often
>>this leads to employment in some of the local bike shops.
>>

>
> Do you think that he will find a used set of SPD-SL? Probably not.
>
>
> Life is Good!
> Jeff


Oh, it's quite possible. . . we get tons of great stuff . . . I know there
are SPD-R pedals pretty often. . . not sure if there are any SLs right now
though. . . it's always worth a look. . . .

Trips For Kids / The Re-Cyclery
610 Fourth Street
San Rafael, CA 94901
(415) 458-2986
 
In article <[email protected]>,
John Thompson <[email protected]> wrote:

> On 2006-01-31, Leo Lichtman <[email protected]> wrote:
>
> > "damyth" wrote: (clip) Go to a good bike shop and ask them to put a
> > 'helicoil' in the pedal eye. If you're mechanically inclined, and have the
> > right tools, you can perform this procedure yourself. If done properly the
> > crank will be better than new. (clip)

>
> > All true. A Helicoil is tougher and more durable than any aluminum thread.
> > It is extremely unlikely that you would have the right tools and still be
> > asking this question. And the tools ain't cheap. You need a special size
> > drill bit, which in this instance will probably be too big to fit in your
> > pistol drill. Then you need a special tap. And then an insertion tool.
> > You could probably replace the crank set for less money than it would cost
> > to buy all that stuff. Let your LBS do it.

>
> The OP will need a left-hand thread helicoil for his left crank arm as
> well.


Buy the right hand thread and run a
3D inversion: (x,y,z) |-> (-x,-y, -z).
Less expensive, and no need to buy a 4D rotation box.

--
Michael Press
 
A Muzi wrote:

>
> Are there LH 9/16-20 Helicoil brand coils/taps ? Ive never seen one.
>


My guess is that after you've buggered up the pedalhole, there usually
isn't enough hole left to get away with a tiny Helicoil
--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl
 
>>>"damyth" wrote: (clip) Go to a good bike shop and ask them to put a
>>>'helicoil' in the pedal eye. If you're mechanically inclined, and have the
>>>right tools, you can perform this procedure yourself. If done properly the
>>>crank will be better than new. (clip)


>>On 2006-01-31, Leo Lichtman <[email protected]> wrote:
>>>All true. A Helicoil is tougher and more durable than any aluminum thread.
>>>It is extremely unlikely that you would have the right tools and still be
>>>asking this question. And the tools ain't cheap. You need a special size
>>>drill bit, which in this instance will probably be too big to fit in your
>>>pistol drill. Then you need a special tap. And then an insertion tool.
>>>You could probably replace the crank set for less money than it would cost
>>>to buy all that stuff. Let your LBS do it.


> John Thompson <[email protected]> wrote:
>>The OP will need a left-hand thread helicoil for his left crank arm as
>>well.


Michael Press wrote:
> Buy the right hand thread and run a
> 3D inversion: (x,y,z) |-> (-x,-y, -z).
> Less expensive, and no need to buy a 4D rotation box.


This is actually not so silly.
Steel sleeves with 9/16 inside and 5/8" outer thread, with
matching reamer and tap are standard service items at better
LBS anywhere. Vendors from Germany, UK, Japan supply
interchangeable sleeves/tools so there seems to be something
like uniformity if not an actual standard.

Are there LH 9/16-20 Helicoil brand coils/taps ? Ive never
seen one.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
 
"M-gineering" wrote: My guess is that after you've buggered up the
pedalhole, there usually isn't enough hole left to get away with a tiny
Helicoil
^^^^^^^^^^^^^^^^^
9/16" is not a tiny Helicoil. Generally a stripped or buggered thread can
be tapped with the proper Helicoil tap to provide a perfect fit for the
replacement thread. BTW, Helicoil even makes inserts that are designed for
the case where there is not enough parent material left to hold the
replacement thread. You tap way oversize, and the thread the Helicoil into
a Helicoil. Probably not available for LH threads, though.
 
In article <[email protected]>,
A Muzi <[email protected]> wrote:

> >>>"damyth" wrote: (clip) Go to a good bike shop and ask them to put a
> >>>'helicoil' in the pedal eye. If you're mechanically inclined, and have the
> >>>right tools, you can perform this procedure yourself. If done properly the
> >>>crank will be better than new. (clip)

>
> >>On 2006-01-31, Leo Lichtman <[email protected]> wrote:
> >>>All true. A Helicoil is tougher and more durable than any aluminum thread.
> >>>It is extremely unlikely that you would have the right tools and still be
> >>>asking this question. And the tools ain't cheap. You need a special size
> >>>drill bit, which in this instance will probably be too big to fit in your
> >>>pistol drill. Then you need a special tap. And then an insertion tool.
> >>>You could probably replace the crank set for less money than it would cost
> >>>to buy all that stuff. Let your LBS do it.

>
> > John Thompson <[email protected]> wrote:
> >>The OP will need a left-hand thread helicoil for his left crank arm as
> >>well.

>
> Michael Press wrote:
> > Buy the right hand thread and run a
> > 3D inversion: (x,y,z) |-> (-x,-y, -z).
> > Less expensive, and no need to buy a 4D rotation box.

>
> This is actually not so silly.


Drat!

> Steel sleeves with 9/16 inside and 5/8" outer thread, with
> matching reamer and tap are standard service items at better
> LBS anywhere. Vendors from Germany, UK, Japan supply
> interchangeable sleeves/tools so there seems to be something
> like uniformity if not an actual standard.
>
> Are there LH 9/16-20 Helicoil brand coils/taps ? Ive never
> seen one.


Are the threads really 9/16-20? I see 9/16-18.

<http://www.newmantools.com/price/stkpr04.htm>

--
Michael Press
 
> "M-gineering" wrote: My guess is that after you've buggered up the
> pedalhole, there usually isn't enough hole left to get away with a tiny
> Helicoil


Leo Lichtman wrote:
> 9/16" is not a tiny Helicoil. Generally a stripped or buggered thread can
> be tapped with the proper Helicoil tap to provide a perfect fit for the
> replacement thread. BTW, Helicoil even makes inserts that are designed for
> the case where there is not enough parent material left to hold the
> replacement thread. You tap way oversize, and the thread the Helicoil into
> a Helicoil. Probably not available for LH threads, though.


By "tiny Helicoil" I assumed he was referring to the
Helicoil's small section. Th usual repair piece is a more
substantial insert, not just an open coil.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
 
>>>>>"damyth" wrote: (clip) Go to a good bike shop and ask them to put a
>>>>>'helicoil' in the pedal eye. If you're mechanically inclined, and have the
>>>>>right tools, you can perform this procedure yourself. If done properly the
>>>>>crank will be better than new. (clip)


>>>>On 2006-01-31, Leo Lichtman <[email protected]> wrote:
>>>>>All true. A Helicoil is tougher and more durable than any aluminum thread.
>>>>>It is extremely unlikely that you would have the right tools and still be
>>>>>asking this question. And the tools ain't cheap. You need a special size
>>>>>drill bit, which in this instance will probably be too big to fit in your
>>>>>pistol drill. Then you need a special tap. And then an insertion tool.
>>>>>You could probably replace the crank set for less money than it would cost
>>>>>to buy all that stuff. Let your LBS do it.


>>> John Thompson <[email protected]> wrote:
>>>>The OP will need a left-hand thread helicoil for his left crank arm as
>>>>well.


>>Michael Press wrote:
>>>Buy the right hand thread and run a
>>>3D inversion: (x,y,z) |-> (-x,-y, -z).
>>>Less expensive, and no need to buy a 4D rotation box.


> A Muzi <[email protected]> wrote:
>>This is actually not so silly.
>>Steel sleeves with 9/16 inside and 5/8" outer thread, with
>>matching reamer and tap are standard service items at better
>>LBS anywhere. Vendors from Germany, UK, Japan supply
>>interchangeable sleeves/tools so there seems to be something
>>like uniformity if not an actual standard.
>>Are there LH 9/16-20 Helicoil brand coils/taps ? Ive never
>>seen one.


Michael Press wrote:
> Are the threads really 9/16-20? I see 9/16-18.
> <http://www.newmantools.com/price/stkpr04.htm>


Bicycle pedals are 9/16 x 20
Or 1/2 x 20
and at one time 14mm x 1.25
but never 9/16 x 18

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971