Crank arm length question - Cycling Mob: Road Cycling, Mountain Biking and More

05-17-2004, 07:06 AM

The root question:

How do I determine the appropriate starting-point for crank-arm
length?

The background:

I have posted in the past about a minor soreness across the top of my
kneecap which shows up several miles into a ride, and which always goes
away by the next day. I have raised my seat as much as I can without
rocking my hips, and the last adjustment of 3mm or so a month ago helped
significantly, but not completely. Some other reading I've done has
indicated that a too-long crank arm can contribute to knee soreness,
which of course brings up the question of how to determine the correct
length. My current ones are 175mm, and I wear pants with a 32 inch
inseam (I haven't measured my crotch-to-ground height yet). Is it
likely that a shorter crank might help? If so, how short?

--
Remove the ns_ from if replying by e-mail (but keep posts in the
newsgroups if possible).

05-17-2004, 08:27 AM

On Mon, 17 May 2004 10:06:31 -0400, David Kerber
<ns_dkerber@ns_ids.net> wrote:

>The root question:
>
> How do I determine the appropriate starting-point for crank-arm
>length?
>
>

Find a helpful bike shop that will let you try different lengths?

>The background:
>
>I have posted in the past about a minor soreness across the top of my
>kneecap which shows up several miles into a ride, and which always goes
>away by the next day. I have raised my seat as much as I can without
>rocking my hips, and the last adjustment of 3mm or so a month ago helped
>significantly, but not completely. Some other reading I've done has
>indicated that a too-long crank arm can contribute to knee soreness,
>which of course brings up the question of how to determine the correct
>length. My current ones are 175mm, and I wear pants with a 32 inch
>inseam (I haven't measured my crotch-to-ground height yet). Is it
>likely that a shorter crank might help? If so, how short?

Have you tried moving the seat forward? That took away my upper
kneecap aches. I've even lowered the saddle down a bit, having raised
it again and again while the seat was back, and things are fine.

A discussion of crank length, with links to other articles-

[Only registered and activated users can see links. ]

05-17-2004, 08:27 AM

On Mon, 17 May 2004 10:06:31 -0400, David Kerber
<ns_dkerber@ns_ids.net> wrote:

>The root question:
>
> How do I determine the appropriate starting-point for crank-arm
>length?
>
>

Find a helpful bike shop that will let you try different lengths?

>The background:
>
>I have posted in the past about a minor soreness across the top of my
>kneecap which shows up several miles into a ride, and which always goes
>away by the next day. I have raised my seat as much as I can without
>rocking my hips, and the last adjustment of 3mm or so a month ago helped
>significantly, but not completely. Some other reading I've done has
>indicated that a too-long crank arm can contribute to knee soreness,
>which of course brings up the question of how to determine the correct
>length. My current ones are 175mm, and I wear pants with a 32 inch
>inseam (I haven't measured my crotch-to-ground height yet). Is it
>likely that a shorter crank might help? If so, how short?

Have you tried moving the seat forward? That took away my upper
kneecap aches. I've even lowered the saddle down a bit, having raised
it again and again while the seat was back, and things are fine.

A discussion of crank length, with links to other articles-

[Only registered and activated users can see links. ]

05-17-2004, 08:27 AM

On Mon, 17 May 2004 10:06:31 -0400, David Kerber
<ns_dkerber@ns_ids.net> wrote:

>The root question:
>
> How do I determine the appropriate starting-point for crank-arm
>length?
>
>

Find a helpful bike shop that will let you try different lengths?

>The background:
>
>I have posted in the past about a minor soreness across the top of my
>kneecap which shows up several miles into a ride, and which always goes
>away by the next day. I have raised my seat as much as I can without
>rocking my hips, and the last adjustment of 3mm or so a month ago helped
>significantly, but not completely. Some other reading I've done has
>indicated that a too-long crank arm can contribute to knee soreness,
>which of course brings up the question of how to determine the correct
>length. My current ones are 175mm, and I wear pants with a 32 inch
>inseam (I haven't measured my crotch-to-ground height yet). Is it
>likely that a shorter crank might help? If so, how short?

Have you tried moving the seat forward? That took away my upper
kneecap aches. I've even lowered the saddle down a bit, having raised
it again and again while the seat was back, and things are fine.

A discussion of crank length, with links to other articles-

[Only registered and activated users can see links. ]

05-17-2004, 08:27 AM

On Mon, 17 May 2004 10:06:31 -0400, David Kerber
<ns_dkerber@ns_ids.net> wrote:

>The root question:
>
> How do I determine the appropriate starting-point for crank-arm
>length?
>
>

Find a helpful bike shop that will let you try different lengths?

>The background:
>
>I have posted in the past about a minor soreness across the top of my
>kneecap which shows up several miles into a ride, and which always goes
>away by the next day. I have raised my seat as much as I can without
>rocking my hips, and the last adjustment of 3mm or so a month ago helped
>significantly, but not completely. Some other reading I've done has
>indicated that a too-long crank arm can contribute to knee soreness,
>which of course brings up the question of how to determine the correct
>length. My current ones are 175mm, and I wear pants with a 32 inch
>inseam (I haven't measured my crotch-to-ground height yet). Is it
>likely that a shorter crank might help? If so, how short?

Have you tried moving the seat forward? That took away my upper
kneecap aches. I've even lowered the saddle down a bit, having raised
it again and again while the seat was back, and things are fine.

A discussion of crank length, with links to other articles-

[Only registered and activated users can see links. ]

05-17-2004, 08:27 AM

On Mon, 17 May 2004 10:06:31 -0400, David Kerber
<ns_dkerber@ns_ids.net> wrote:

>The root question:
>
> How do I determine the appropriate starting-point for crank-arm
>length?
>
>

Find a helpful bike shop that will let you try different lengths?

>The background:
>
>I have posted in the past about a minor soreness across the top of my
>kneecap which shows up several miles into a ride, and which always goes
>away by the next day. I have raised my seat as much as I can without
>rocking my hips, and the last adjustment of 3mm or so a month ago helped
>significantly, but not completely. Some other reading I've done has
>indicated that a too-long crank arm can contribute to knee soreness,
>which of course brings up the question of how to determine the correct
>length. My current ones are 175mm, and I wear pants with a 32 inch
>inseam (I haven't measured my crotch-to-ground height yet). Is it
>likely that a shorter crank might help? If so, how short?

Have you tried moving the seat forward? That took away my upper
kneecap aches. I've even lowered the saddle down a bit, having raised
it again and again while the seat was back, and things are fine.

A discussion of crank length, with links to other articles-

[Only registered and activated users can see links. ]

05-17-2004, 10:50 AM

In article <[Only registered and activated users can see links. ]>,
[Only registered and activated users can see links. ] says...
> On Mon, 17 May 2004 10:06:31 -0400, David Kerber
> <ns_dkerber@ns_ids.net> wrote:
>
> >The root question:
> >
> > How do I determine the appropriate starting-point for crank-arm
> >length?
> >
> >
>
> Find a helpful bike shop that will let you try different lengths?

>
>
> >The background:
> >
> >I have posted in the past about a minor soreness across the top of my
> >kneecap which shows up several miles into a ride, and which always goes
> >away by the next day. I have raised my seat as much as I can without
> >rocking my hips, and the last adjustment of 3mm or so a month ago helped
> >significantly, but not completely. Some other reading I've done has
> >indicated that a too-long crank arm can contribute to knee soreness,
> >which of course brings up the question of how to determine the correct
> >length. My current ones are 175mm, and I wear pants with a 32 inch
> >inseam (I haven't measured my crotch-to-ground height yet). Is it
> >likely that a shorter crank might help? If so, how short?
>
>
> Have you tried moving the seat forward? That took away my upper
> kneecap aches. I've even lowered the saddle down a bit, having raised
> it again and again while the seat was back, and things are fine.

The seat's already close to as far forward as it can go, but I'll see if
I've got any room left at all.

> A discussion of crank length, with links to other articles-
>
> [Only registered and activated users can see links. ]

Thanks for that.

--
Remove the ns_ from if replying by e-mail (but keep posts in the
newsgroups if possible).

05-17-2004, 10:50 AM

In article <[Only registered and activated users can see links. ]>,
[Only registered and activated users can see links. ] says...
> On Mon, 17 May 2004 10:06:31 -0400, David Kerber
> <ns_dkerber@ns_ids.net> wrote:
>
> >The root question:
> >
> > How do I determine the appropriate starting-point for crank-arm
> >length?
> >
> >
>
> Find a helpful bike shop that will let you try different lengths?

>
>
> >The background:
> >
> >I have posted in the past about a minor soreness across the top of my
> >kneecap which shows up several miles into a ride, and which always goes
> >away by the next day. I have raised my seat as much as I can without
> >rocking my hips, and the last adjustment of 3mm or so a month ago helped
> >significantly, but not completely. Some other reading I've done has
> >indicated that a too-long crank arm can contribute to knee soreness,
> >which of course brings up the question of how to determine the correct
> >length. My current ones are 175mm, and I wear pants with a 32 inch
> >inseam (I haven't measured my crotch-to-ground height yet). Is it
> >likely that a shorter crank might help? If so, how short?
>
>
> Have you tried moving the seat forward? That took away my upper
> kneecap aches. I've even lowered the saddle down a bit, having raised
> it again and again while the seat was back, and things are fine.

The seat's already close to as far forward as it can go, but I'll see if
I've got any room left at all.

> A discussion of crank length, with links to other articles-
>
> [Only registered and activated users can see links. ]

Thanks for that.

--
Remove the ns_ from if replying by e-mail (but keep posts in the
newsgroups if possible).

05-17-2004, 10:50 AM

In article <[Only registered and activated users can see links. ]>,
[Only registered and activated users can see links. ] says...
> On Mon, 17 May 2004 10:06:31 -0400, David Kerber
> <ns_dkerber@ns_ids.net> wrote:
>
> >The root question:
> >
> > How do I determine the appropriate starting-point for crank-arm
> >length?
> >
> >
>
> Find a helpful bike shop that will let you try different lengths?

>
>
> >The background:
> >
> >I have posted in the past about a minor soreness across the top of my
> >kneecap which shows up several miles into a ride, and which always goes
> >away by the next day. I have raised my seat as much as I can without
> >rocking my hips, and the last adjustment of 3mm or so a month ago helped
> >significantly, but not completely. Some other reading I've done has
> >indicated that a too-long crank arm can contribute to knee soreness,
> >which of course brings up the question of how to determine the correct
> >length. My current ones are 175mm, and I wear pants with a 32 inch
> >inseam (I haven't measured my crotch-to-ground height yet). Is it
> >likely that a shorter crank might help? If so, how short?
>
>
> Have you tried moving the seat forward? That took away my upper
> kneecap aches. I've even lowered the saddle down a bit, having raised
> it again and again while the seat was back, and things are fine.

The seat's already close to as far forward as it can go, but I'll see if
I've got any room left at all.

> A discussion of crank length, with links to other articles-
>
> [Only registered and activated users can see links. ]

Thanks for that.

--
Remove the ns_ from if replying by e-mail (but keep posts in the
newsgroups if possible).

05-17-2004, 10:50 AM

In article <[Only registered and activated users can see links. ]>,
[Only registered and activated users can see links. ] says...
> On Mon, 17 May 2004 10:06:31 -0400, David Kerber
> <ns_dkerber@ns_ids.net> wrote:
>
> >The root question:
> >
> > How do I determine the appropriate starting-point for crank-arm
> >length?
> >
> >
>
> Find a helpful bike shop that will let you try different lengths?

>
>
> >The background:
> >
> >I have posted in the past about a minor soreness across the top of my
> >kneecap which shows up several miles into a ride, and which always goes
> >away by the next day. I have raised my seat as much as I can without
> >rocking my hips, and the last adjustment of 3mm or so a month ago helped
> >significantly, but not completely. Some other reading I've done has
> >indicated that a too-long crank arm can contribute to knee soreness,
> >which of course brings up the question of how to determine the correct
> >length. My current ones are 175mm, and I wear pants with a 32 inch
> >inseam (I haven't measured my crotch-to-ground height yet). Is it
> >likely that a shorter crank might help? If so, how short?
>
>
> Have you tried moving the seat forward? That took away my upper
> kneecap aches. I've even lowered the saddle down a bit, having raised
> it again and again while the seat was back, and things are fine.

The seat's already close to as far forward as it can go, but I'll see if
I've got any room left at all.

> A discussion of crank length, with links to other articles-
>
> [Only registered and activated users can see links. ]

Thanks for that.

--
Remove the ns_ from if replying by e-mail (but keep posts in the
newsgroups if possible).