remove sq taper crank - puller thread damaged

ellis said:

Anything else can try to get this crank arm off?

First, unscrew the axle/crank arm bolt just a few turns, and ride
carfefully the bike on a flat parking lot - the crank arm may suddenly
break loose, don't harm yourself while doing this on a technical
downhill ;o).

The hammer can also be used ain a counterintuitive but very efficient
way on a square axle, by striking on the side of the crank, in the
diagonal of the square. see p18 of
http://www.bbinstitute.com/BM5%20chap%2020.pdf for a very clear sketch.

NB : on a splined (not squared) axle, these two methods may probably be
unadapted.
..

"ellis" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

I've tried using a mallet to hammer it out off the BB spindle, put the
drive
side crank arm back on and tried jerking and pulling it out, but of course
it's rusted or ground shut in place and won't budge.

Anything else can try to get this crank arm off?

TIA.

Ditto on the loosen the crank bolt and ride around. It works everytime.
But be careful don't go very far from home, as it usually comes loose
unexpectedly.

ellis said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

I've tried using a mallet to hammer it out off the BB spindle, put the drive
side crank arm back on and tried jerking and pulling it out, but of course
it's rusted or ground shut in place and won't budge.

Anything else can try to get this crank arm off?

TIA.

This question comes up often - see http://tinyurl.com/p7f8z
My favorite technique is sawing off the arm. It's awkward to cut so
close to the frame, but a hacksaw will tear right through most cranks.
It helps to remove the pedal and secure the crank in a vise.

In your case, you might want to try grinding away the damaged portion
of the crank so that you can thread the tool into it.

-Vee

ellis said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

I've tried using a mallet to hammer it out off the BB spindle, put the drive
side crank arm back on and tried jerking and pulling it out, but of course
it's rusted or ground shut in place and won't budge.

Anything else can try to get this crank arm off?

If you aren't concerned about the possibility of buggering the end of
the BB shell, an automotive tie rod end separator (also called a
"pickle fork", available as a loaner tool at many auto parts chain
stores like Autozone) will usually pop it right off. Wedge the fork
behind the arm, give the other end of it a whack with a BFH, and the
crank will probably fall off. A small gear puller will often work,
and poses no hazard to the BB as long as the end of the ram screw
isn't so small that it chews up the hole in the shaft. And, as a last
resort, you can always destructively remove it by splitting the end
with a chisel or a hacksaw. Use appropriate caution with all of
these; none are free of risk of either injury to the user or damage to
the bike.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Werehatrack said:

A small gear puller will often work,
and poses no hazard to the BB as long as the end of the ram screw
isn't so small that it chews up the hole in the shaft.
the bike.

Gentlemen, gentleman... riding without a crank bolt? hammers? chisels
and hacksaws ?

There's a kinder, gentler way. Put the bolt back in the crank hole,
complete with washer, bring it down within a couple mm of tight. Then
use a small gear puller to gently pull the arm off. The bolt/washer
will prevent anything abrupt from happening when it comes loose.

The arm can still be used if you don't mind having to use a puller
whenever you want to remove it.

On Tue, 04 Jul 2006 17:08:25 GMT, - Bob - <[email hidden]>

Quoted message said:

Werehatrack said:

A small gear puller will often work,
and poses no hazard to the BB as long as the end of the ram screw
isn't so small that it chews up the hole in the shaft.
the bike.

Gentlemen, gentleman... riding without a crank bolt? hammers? chisels
and hacksaws ?

There's a kinder, gentler way. Put the bolt back in the crank hole,
complete with washer, bring it down within a couple mm of tight. Then
use a small gear puller to gently pull the arm off. The bolt/washer
will prevent anything abrupt from happening when it comes loose.

The arm can still be used if you don't mind having to use a puller
whenever you want to remove it.

That's part of why I mentioned it, but from experience I can state
that it doesn't always work (for a variety of potential reasons that
may or may not apply in a given case) and it's not a practical
approach if the appropriate puller isn't at hand or readily available.
That's why the alternatives (with their hazards) were listed.

BTW, the "ride with the bolt loose" method doesn't always chew up the
crank; used with enough care, it's as safe as any other.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

ellis said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

I've tried using a mallet to hammer it out off the BB spindle, put the drive
side crank arm back on and tried jerking and pulling it out, but of course
it's rusted or ground shut in place and won't budge.

Anything else can try to get this crank arm off?

TIA.

http://groups.google.com/groups?query=remove+crank+damaged+extractor+thread&sa=N&tab=wg&q=remove%20crank%20damaged%20extractor%20thread
Kinky Cowboy*

*Batteries not included
May contain traces of nuts
Your milage may vary

<[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

ellis said:

Anything else can try to get this crank arm off?

First, unscrew the axle/crank arm bolt just a few turns, and ride
carfefully the bike on a flat parking lot - the crank arm may suddenly
break loose, don't harm yourself while doing this on a technical
downhill ;o).

The hammer can also be used ain a counterintuitive but very efficient
way on a square axle, by striking on the side of the crank, in the
diagonal of the square. see p18 of
http://www.bbinstitute.com/BM5%20chap%2020.pdf for a very clear sketch.

NB : on a splined (not squared) axle, these two methods may probably be
unadapted.
.

Merci! I'll try that.

- Bob - said:

There's a kinder, gentler way. Put the bolt back in the crank hole,
complete with washer, bring it down within a couple mm of tight. Then
use a small gear puller to gently pull the arm off. The bolt/washer
will prevent anything abrupt from happening when it comes loose.

The problem with gear pullers is that it's very difficult to get the
gear puller's arms to grab around the crankarm's spider, stay centered,
and hold on. This is more of a problem with right crankarms (obviously)
and odd-number spiders.

Jeff

JeffWills said:

- Bob - said:

There's a kinder, gentler way. Put the bolt back in the crank hole,
complete with washer, bring it down within a couple mm of tight. Then
use a small gear puller to gently pull the arm off. The bolt/washer
will prevent anything abrupt from happening when it comes loose.

The problem with gear pullers is that it's very difficult to get the
gear puller's arms to grab around the crankarm's spider, stay centered,
and hold on. This is more of a problem with right crankarms (obviously)
and odd-number spiders.

The OP said it was a left arm.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

ellis said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

Take it a good shop that can chase or re-tap the threads ??

- Don Gillies
San Diego, CA

ellis said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

Have you considered taking it to a good shop that can chase or re-tap the
threads ?

- Don Gillies
San Diego, CA

You could try chasing out the threads (special tool) or using the
appropriate size bearing puller. Special tool also, but may be more
available, try an automotive repair shop if your LBS isn't equipped..

- -
Comments and opinions compliments of,
"Your Friendly Neighborhood Wheelman"

My web Site:
http://geocities.com/czcorner

To E-mail me:
ChrisZCorner "at" webtv "dot" net

ellis said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

I've tried using a mallet to hammer it out off the BB spindle, put the drive
side crank arm back on and tried jerking and pulling it out, but of course
it's rusted or ground shut in place and won't budge.

Anything else can try to get this crank arm off?

Bicycle Research makes a crank thread chaser that may fix the threads
enough to allow you to use the proper tool. Perhaps your bike shop
already has one? If not, try here:

http://www.biketoolsetc.com/index.cgi?id=739728964948&d=single&c=Tools&sc=Crank&tc=Thread%20Repair&item_id=BR-TC8

VAR makes a kit for rethreading arms to a larger diameter, but it is
considerably more expensive:

http://www.biketoolsetc.com/index.cgi?id=739728964948&d=single&c=Tools&sc=Crank&tc=Thread%20Repair&item_id=VR-PE11000

Once again, perhaps your bike shop already has one of these.

--

John ([email hidden])

ellis said:

Quoted message said:

I'm trying to remove a left crank arm on an old mtb where the thread for
crank puller (Park CCP-2) is damaged by side swapping a city curb: it
flattened just the part where the thread starts, so the crank puller won't
thread in.

Quoted message said:

Quoted message said:

Anything else can try to get this crank arm off?

Coming in late on this thread; please forgive me if this has been
suggested previously. Have you tried using a gear puller?