Lace-over with small ERD difference

I have a Mavic CPX21 rim that came with my bike that has cracked after
28,000 miles. I'd like to do a lace-over with a new rim, but it looks
like the CPX21 was OEM and I don't know if I can get one. The CPX22 is
available, though, which looks like pretty much the same rim but with
an eyelet. However, Damon Rinard's spoke-length calculator database
gives the ERD of the CXP21 as 601.5 and the CXP22S as 599.5. Is that
too much different? If so, does anyone have any other suggestions? It
is for a real wheel, Ultegra hub, 9 speed, purchased in early 2002, and
I don't race.

On Nov 29, 6:55*pm, Jim West wrote:
I have a Mavic CPX21 rim that came with my bike that has cracked after
28,000 miles. I'd like to do a lace-over with a new rim, but it looks
like the CPX21 was OEM and I don't know if I can get one. The CPX22 is
available, though, which looks like pretty much the same rim but with
an eyelet. However, Damon Rinard's spoke-length calculator database
gives the ERD of the CXP21 as 601.5 and the CXP22S as 599.5.

Close enough for *me*. Have a look at the back of the nipples and see
how far the spokes are threaded before you make your decision. CXP22
isn't eyeletted AFAIK.

On Nov 29, 4:55*pm, Jim West wrote:
I have a Mavic CPX21 rim that came with my bike that has cracked after
28,000 miles. I'd like to do a lace-over with a new rim, but it looks
like the CPX21 was OEM and I don't know if I can get one. The CPX22 is
available, though, which looks like pretty much the same rim but with
an eyelet. However, Damon Rinard's spoke-length calculator database
gives the ERD of the CXP21 as 601.5 and the CXP22S as 599.5. Is that
too much different? If so, does anyone have any other suggestions? It
is for a real wheel, Ultegra hub, 9 speed, purchased in early 2002, and
I don't race.

Like LO alludes to, your main concern is that the nipples will bottom
out on the threads, and you won't be able to tension the wheel. I had
that problem when Spocalc gave the ERD of a rim as 606, but it was
actually 600, so I wound up with too-long spokes (even that wasn't a
deal-breaker, the wheel still built up OK, but some of the drive-side
nipples bottomed out to get proper tension). In your situation, you'll
only need 1mm of additional thread (less, actually, unless it's
radial) to pull it off. I'd really be surprised if you had any
problems.

On 2008-11-30, Hank wrote:
On Nov 29, 4:55Â*pm, Jim West wrote:
I have a Mavic CPX21 rim that came with my bike that has cracked after
28,000 miles. I'd like to do a lace-over with a new rim, but it looks
like the CPX21 was OEM and I don't know if I can get one. The CPX22 is
available, though, which looks like pretty much the same rim but with
an eyelet. However, Damon Rinard's spoke-length calculator database
gives the ERD of the CXP21 as 601.5 and the CXP22S as 599.5. Is that
too much different? If so, does anyone have any other suggestions? It
is for a real wheel, Ultegra hub, 9 speed, purchased in early 2002, and
I don't race.

Like LO alludes to, your main concern is that the nipples will bottom
out on the threads, and you won't be able to tension the wheel. I had
that problem when Spocalc gave the ERD of a rim as 606, but it was
actually 600, so I wound up with too-long spokes (even that wasn't a
deal-breaker, the wheel still built up OK, but some of the drive-side
nipples bottomed out to get proper tension). In your situation, you'll
only need 1mm of additional thread (less, actually, unless it's
radial) to pull it off. I'd really be surprised if you had any
problems.

I took a look and it looks like it will be okay so I'll give it a try.
Worst thing that could happen is I'll have to buy some spokes if it
doesn't work out. Thanks for the help, folks.

On 2008-11-30, landotter wrote:

CXP22
isn't eyeletted AFAIK.

I saw a web site that said it was eyeletted, but after seeing your post
I went to the Mavic site, and under "caracteristics" (sic) it says
(http://www.mavic.com/road/products/c...95216.2.aspx):

"6106 aluminum alloy
Aerodynamic profile
Clincher
External wear indicator
Non eyeletted
Pinned
Single eyelet
Traditional drilling"

Both Non eyeletted and Single eyelet? Anyone know what that means?

On Nov 29, 9:07*pm, Jim West wrote:
On 2008-11-30, landotter wrote:



CXP22
isn't eyeletted AFAIK.

I saw a web site that said it was eyeletted, but after seeing your post
I went to the Mavic site, and under "caracteristics" (sic) it says
(http://www.mavic.com/road/products/c...95216.2.aspx):

"6106 aluminum alloy
Aerodynamic profile
Clincher
External wear indicator
Non eyeletted
Pinned
Single eyelet
Traditional drilling"

Both Non eyeletted and Single eyelet? Anyone know what that means?

Means that there's a eyeletted version about along with the more
common non eyeletted one. I highly doubt you could find one with
eyelets--my google doesn't show one.

Also consider the Alex R390, ERD 603, so if the back of your current
build shows the spoke flush, it will bite fine. It's a cheaper and
stronger rim. Better alloy with eyelets to boot.

Good luck and have fun!

"landotter" wrote:
On Nov 29, 9:07 pm, Jim West wrote:
On 2008-11-30, landotter wrote:



CXP22
isn't eyeletted AFAIK.
I saw a web site that said it was eyeletted, but after seeing your post
I went to the Mavic site, and under "caracteristics" (sic) it says
(http://www.mavic.com/road/products/c...95216.2.aspx):

"6106 aluminum alloy
Aerodynamic profile
Clincher
External wear indicator
Non eyeletted
Pinned
Single eyelet
Traditional drilling"

Both Non eyeletted and Single eyelet? Anyone know what that means?

Means that there's a eyeletted version about along with the more
common non eyeletted one. I highly doubt you could find one with
eyelets--my google doesn't show one.

Also consider the Alex R390, ERD 603, so if the back of your current
build shows the spoke flush, it will bite fine. It's a cheaper and
stronger rim. Better alloy with eyelets to boot.

Good luck and have fun!

butbutbut, Alex® rims lack European Heritage & Mystique™!!!

--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the
precipitate. - Anon?

In article ,
Jim West wrote:

On 2008-11-30, landotter wrote:

CXP22
isn't eyeletted AFAIK.

I saw a web site that said it was eyeletted, but after seeing your post
I went to the Mavic site, and under "caracteristics" (sic) it says
(http://www.mavic.com/road/products/c...95216.2.aspx):

"6106 aluminum alloy
Aerodynamic profile
Clincher
External wear indicator
Non eyeletted
Pinned
Single eyelet
Traditional drilling"

Both Non eyeletted and Single eyelet? Anyone know what that means?

It means that as usual Mavic isn't paying attention to the details.

Jim West skrev:

Both Non eyeletted and Single eyelet? Anyone know what that means?

Could be that Mavic delivers the rim in two different versions; with
or without eylets. It is very common for rim manufacturers to make the
same rim in different configurations. In the Spocalc db the CXP 22 is
listed in both a CXP22N (ERD 598,5) and a CXP22S(ERD 599,5) version
with slightly different ERD's. The letter designation seems to point
to a N=Non eyletted and S=Single eyletted.

--
Regards

On Nov 29, 5:55*pm, Jim West wrote:
I have a Mavic CPX21 rim that came with my bike that has cracked after
28,000 miles. I'd like to do a lace-over with a new rim, but it looks
like the CPX21 was OEM and I don't know if I can get one. The CPX22 is
available, though, which looks like pretty much the same rim but with
an eyelet. However, Damon Rinard's spoke-length calculator database
gives the ERD of the CXP21 as 601.5 and the CXP22S as 599.5. Is that
too much different? If so, does anyone have any other suggestions? It
is for a real wheel, Ultegra hub, 9 speed, purchased in early 2002, and
I don't race.

Open Pro is 603mm erd, what we use when we build them.