Replacing a cracked crank

Quoted message said:

I've just bought a second-hand road bike to replace a stolen one, but
I've now noticed that the LH crank has a crack running right across
the eye at the BB end. I can hear it creaking, so I think it may give
up sooner rather than later. The chainset is Campagnolo Avanti, about
10 years old. Since I bought the whole bike for £100, I need to
replace the crank equally cheaply otherwise I've wasted my money. It
doesn't need to be perfect, it just needs not to dump me in the road.

I imagine getting a genuine spare is out of the question, but from
what I've read most of the incompatibilities in chainsets should only
affect the RH crank. I'm hoping that I can get away with replacing
just the LH one with a random part off ebay. It looks like I pretty
much just need one the same length (170mm), with the same fitting
(square taper). Does that seem reasonable or am I being over-
optimistic?

Thanks

/J

Here's what I got when mine cracked at the pedal end:
http://tinyurl.com/yuo567

Quoted message said:

I've just bought a second-hand road bike to replace a stolen one, but
I've now noticed that the LH crank has a crack running right across
the eye at the BB end. I can hear it creaking, so I think it may give
up sooner rather than later. The chainset is Campagnolo Avanti, about
10 years old. Since I bought the whole bike for £100, I need to
replace the crank equally cheaply otherwise I've wasted my money. It
doesn't need to be perfect, it just needs not to dump me in the road.

I imagine getting a genuine spare is out of the question, but from
what I've read most of the incompatibilities in chainsets should only
affect the RH crank. I'm hoping that I can get away with replacing
just the LH one with a random part off ebay. It looks like I pretty
much just need one the same length (170mm), with the same fitting
(square taper). Does that seem reasonable or am I being over-
optimistic?

Thanks

/J

Here's what I got when mine cracked at the pedal end:
http://tinyurl.com/yuo567

Quoted message said:

I've just bought a second-hand road bike to replace a stolen one, but
I've now noticed that the LH crank has a crack running right across
the eye at the BB end. I can hear it creaking, so I think it may give
up sooner rather than later. The chainset is Campagnolo Avanti, about
10 years old. Since I bought the whole bike for £100, I need to
replace the crank equally cheaply otherwise I've wasted my money. It
doesn't need to be perfect, it just needs not to dump me in the road.

I imagine getting a genuine spare is out of the question, but from
what I've read most of the incompatibilities in chainsets should only
affect the RH crank. I'm hoping that I can get away with replacing
just the LH one with a random part off ebay. It looks like I pretty
much just need one the same length (170mm), with the same fitting
(square taper). Does that seem reasonable or am I being over-
optimistic?

Beware that Campy square-taper is not the same as Shimano (which has
become the generic) square-taper. They are the same angle, but
different beginning diameters, so it would either sit too far out, or
too far in, and neither is really good.

it may be a hundred-pound bike, but you want it to be a comfortable,
usable bike. I would suggest looking at a shop near you, or on-line,
for a matching arm. Don't worry about Record/Chorus/Avanti/Whatever,
but do go for campy, to get the right fit.

--

David L. Johnson

And what if you track down these men and kill them, what if you killed
all of us? From every corner of Europe, hundreds, thousands would
rise up to take our places. Even Nazis can't kill that fast.
-- Paul Henreid (Casablanca).

Quoted message said:

I've just bought a second-hand road bike to replace a stolen one, but
I've now noticed that the LH crank has a crack running right across
the eye at the BB end. I can hear it creaking, so I think it may give
up sooner rather than later. The chainset is Campagnolo Avanti, about
10 years old. Since I bought the whole bike for £100, I need to
replace the crank equally cheaply otherwise I've wasted my money. It
doesn't need to be perfect, it just needs not to dump me in the road.

I imagine getting a genuine spare is out of the question, but from
what I've read most of the incompatibilities in chainsets should only
affect the RH crank. I'm hoping that I can get away with replacing
just the LH one with a random part off ebay. It looks like I pretty
much just need one the same length (170mm), with the same fitting
(square taper). Does that seem reasonable or am I being over-
optimistic?

Beware that Campy square-taper is not the same as Shimano (which has
become the generic) square-taper. They are the same angle, but
different beginning diameters, so it would either sit too far out, or
too far in, and neither is really good.

it may be a hundred-pound bike, but you want it to be a comfortable,
usable bike. I would suggest looking at a shop near you, or on-line,
for a matching arm. Don't worry about Record/Chorus/Avanti/Whatever,
but do go for campy, to get the right fit.

--

David L. Johnson

And what if you track down these men and kill them, what if you killed
all of us? From every corner of Europe, hundreds, thousands would
rise up to take our places. Even Nazis can't kill that fast.
-- Paul Henreid (Casablanca).

In article <[email hidden]>,

tacos said:

bottombracket tapers have two differant tapers ISO and JIS there is a
4.5 mm differance between tham

http://sheldonbrown.com/bbtaper.html

hope this helps

What he said. Unfortunately, you have a Campy (ISO) crank. I say that
because the JIS ones are very common, and a typical bike shop will have
one kicking around for $10-20.

You can probably eBay one, or order an acceptable one from a local shop.
A good, road-oriented shop is likely to have ISO rh cranks in stock.

--
Ryan Cousineau [email hidden] http://www.wiredcola.com/
"My scenarios may give the impression I could be an excellent crook.
Not true - I am a talented lawyer." - Sandy in rec.bicycles.racing

In article <[email hidden]>,

tacos said:

bottombracket tapers have two differant tapers ISO and JIS there is a
4.5 mm differance between tham

http://sheldonbrown.com/bbtaper.html

hope this helps

What he said. Unfortunately, you have a Campy (ISO) crank. I say that
because the JIS ones are very common, and a typical bike shop will have
one kicking around for $10-20.

You can probably eBay one, or order an acceptable one from a local shop.
A good, road-oriented shop is likely to have ISO rh cranks in stock.

--
Ryan Cousineau [email hidden] http://www.wiredcola.com/
"My scenarios may give the impression I could be an excellent crook.
Not true - I am a talented lawyer." - Sandy in rec.bicycles.racing

In article
<[email hidden]>
,

Quoted message said:

I've just bought a second-hand road bike to replace a stolen one, but
I've now noticed that the LH crank has a crack running right across
the eye at the BB end. I can hear it creaking, so I think it may give
up sooner rather than later. The chainset is Campagnolo Avanti, about
10 years old. Since I bought the whole bike for £100, I need to
replace the crank equally cheaply otherwise I've wasted my money. It
doesn't need to be perfect, it just needs not to dump me in the road.

I imagine getting a genuine spare is out of the question, but from
what I've read most of the incompatibilities in chainsets should only
affect the RH crank. I'm hoping that I can get away with replacing
just the LH one with a random part off ebay. It looks like I pretty
much just need one the same length (170mm), with the same fitting
(square taper). Does that seem reasonable or am I being over-
optimistic?

Start calling bicycle shops. You may find a crank
in their bin of loose parts.

--
Michael Press

In article
<[email hidden]>
,

Quoted message said:

I've just bought a second-hand road bike to replace a stolen one, but
I've now noticed that the LH crank has a crack running right across
the eye at the BB end. I can hear it creaking, so I think it may give
up sooner rather than later. The chainset is Campagnolo Avanti, about
10 years old. Since I bought the whole bike for £100, I need to
replace the crank equally cheaply otherwise I've wasted my money. It
doesn't need to be perfect, it just needs not to dump me in the road.

I imagine getting a genuine spare is out of the question, but from
what I've read most of the incompatibilities in chainsets should only
affect the RH crank. I'm hoping that I can get away with replacing
just the LH one with a random part off ebay. It looks like I pretty
much just need one the same length (170mm), with the same fitting
(square taper). Does that seem reasonable or am I being over-
optimistic?

Start calling bicycle shops. You may find a crank
in their bin of loose parts.

--
Michael Press

For a LH crank that's pretty immaterial. There's no chainline to worry
about, so provided the replacement crank doesn't bottom out on the taper,
any crank of the correct length will do.

A quick search on eBay for left hand crank turns up half a dozen items
priced from under £1 to about £3.

Nick

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

Quoted message said:

bottombracket tapers have two differant tapers ISO and JIS there is a
4.5 mm differance between tham

http://sheldonbrown.com/bbtaper.html

hope this helps

For a LH crank that's pretty immaterial. There's no chainline to worry
about, so provided the replacement crank doesn't bottom out on the taper,
any crank of the correct length will do.

A quick search on eBay for left hand crank turns up half a dozen items
priced from under £1 to about £3.

Nick

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

Quoted message said:

bottombracket tapers have two differant tapers ISO and JIS there is a
4.5 mm differance between tham

http://sheldonbrown.com/bbtaper.html

hope this helps