Rim Strength ?

Velo Psycho said:

Now... what rims.... the open pro, the CXP-33, or other suggestions?

The CXP33 has no spoke offset. The Open Pro has spoke offset and you
can get more of the tension on the non drive side.

The Velocity Aerohead OC offset and off center permits even more
tension on the non drive side and, in my opinion, this will permit the
strongest wheel. I have had no spoke pull through on the Velocity
rims even though they have no eyelets.

Quoted message said:

I have had no spoke pull through on the Velocity
rims even though they have no eyelets.

Did you use washers on the nipples?

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

Quoted message said:

Velo Psycho said:

Now... what rims.... the open pro, the CXP-33, or other

suggestions?

Quoted message said:

The CXP33 has no spoke offset. The Open Pro has spoke offset and

you

Quoted message said:

can get more of the tension on the non drive side.

The Velocity Aerohead OC offset and off center permits even more
tension on the non drive side and, in my opinion, this will permit

the

Quoted message said:

strongest wheel. I have had no spoke pull through on the Velocity
rims even though they have no eyelets.

Velo Psycho said:

Anyone have an opinion on relative rim strength? (all other things on
the wheel being equal)

The Mavic Open Pro seems to be the standard... but someone made an
argument that the CXP-33, with its triangular shape, is a stronger rim.
I don't know anything about physics, so ... the argument makes sense
to me... but, figured I'd see what other people's experiences are.
I've ridden open pros, and been fine with them. I'm looking to build a
set of wheels for heavy commuting. Already decided on Campy Record
hubs, 36 hole.

Now... what rims.... the open pro, the CXP-33, or other suggestions?

What size tire will you use?
How much do you weigh?

I agree with Paul on the Aerohead OC for the rear. With Campagnolo spoke support angle on the right rear, the Aerohead OC makes a significant improvement... somewhere near 50% on the drive side pulling spokes.

If you are going with 28 mm or wider tires, I have also had very good results with Velocity Dyad rims (using them on our road touring tandem for 7,600 miles with 400+ pound load). As Paul said, they don't have eyelets, but they hold up well. You want to use lube at the nipple/rim interfaces on any rim you use.

Mavic rates the strength of OpenPro and CXP33 as equal. They rate the MA-3 as 15% weaker than the above... and the A719 as 25% stronger than the above Mavic rims.
The small nit that I will pick with Paul is that having no "offset" on the CXP33 makes a very small spoke angle support improvement compared to OpenPro for the rear drive side.
Very small amounts to 0.1 degrees average improved spoke support angle on the CXP-33 over the OpenPro right rear spokes. I used Campagnolo 9/10 speed and 36H 3X in my comparisons.
The Velocity Aerohead improves 0.7 degrees over the OpenPro in this instance. I know it doesn't sound like much, but the load taken up by the left rear spokes is significantly more in an Aeohead OC rear wheel.
I suggest you take some time doing the calculations and comparisons. 4 mm offset of the Velocity Aorohead OC spoke bed makes a difference in durability of the entire wheel.

The quality of the build will have much to say about strength and durability.

Hmmmm..... great info here. I guess to tweak the inquiry, I may have
been a little inaccurate - I commute to work on the bike, but do it
like a training ride. So... I like to run my 23mm tires, or I guess I
could beef up to 25s.

I'll definitely check out some of the other suggested rims on here
though. Thank you.

Quoted message said:

I'm looking to build a
set of wheels for heavy commuting. Already decided on Campy Record
hubs, 36 hole.

Quoted message said:

Now... what rims.... the open pro, the CXP-33, or other suggestions?

Part of the reason the CXP-33 can be built into a stronger wheel is that it
is heavier (480g) than the Open Pro (425g). All else being equal, a heavier
rim will permit higher spoke tension and make for a more durable wheel. Of
course, all else is not equal between those two rims, but the edge would go
to the CXP-33.

I agree with Paul that offset and off-center rims are a good idea, but I
would consider the Velocity Aerohead too light (405g) for heavy commuting.
Rivendell sells a 700C, offset/off-center Velocity Synergy rim in 36 hole.
I'm not sure of the exact quoted weight but it's closer to 500g, and it's
wider which would more easily allow wider commuting tires.

http://www.rivendellbicycles.com/webalog/wheels/18094.html

For off-center rear rims, there's also the similarly-constructed Bontrager
Fairlane and Ritchey Trekking.

Other appropriate rims would include the Velocity Dyad, Sun CR-18, and Alex
Adventurer.

Use butted spokes.

-Bruce-

Bruce Lange said:

> I'm looking to build a

Quoted message said:

set of wheels for heavy commuting. Already decided on Campy Record
hubs, 36 hole.

Quoted message said:

Now... what rims.... the open pro, the CXP-33, or other suggestions?

Part of the reason the CXP-33 can be built into a stronger wheel is that it
is heavier (480g) than the Open Pro (425g). All else being equal, a heavier
rim will permit higher spoke tension and make for a more durable wheel. Of
course, all else is not equal between those two rims, but the edge would go
to the CXP-33.

I agree with Paul that offset and off-center rims are a good idea, but I
would consider the Velocity Aerohead too light (405g) for heavy commuting.
Rivendell sells a 700C, offset/off-center Velocity Synergy rim in 36 hole.
I'm not sure of the exact quoted weight but it's closer to 500g, and it's
wider which would more easily allow wider commuting tires.

http://www.rivendellbicycles.com/webalog/wheels/18094.html

For off-center rear rims, there's also the similarly-constructed Bontrager
Fairlane and Ritchey Trekking.

Other appropriate rims would include the Velocity Dyad, Sun CR-18, and Alex
Adventurer.

Use butted spokes.

-Bruce-

Some of the weight of the CXP33 are "nipple washers" that Mavic uses to fortify the nipple/rim interface. Another part of the weight are "spring fingers" formed between the inner and outer rim walls and used to hold the "nipple washers" in place. There is no mechanical connection of the inner and outer rim walls at the spoke holes on the CXP33 like there is on the OpenPro.
MA-3 is of the same weight class as CXP-33, but is significantly weaker than OpenPro.
My point is: It's not just rim weight, but how the weight is used in material/structural application.

If you can use wider tires, you can benefit from rims like the OC version of 700C Velocity Synergy, Ritchey Trekking OC, Bontrager Fairlane OC. Some of these rims may be available in 36H and some not.

Your weight, riding style, and what will fit your bicycle frame/fork/brakes will tell you what the best combination available is. Fatter tires can not only protect your rims better, but often give you more miles per dollar. Just use caution in selecting tire and rim width combinations.

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

Quoted message said:

Quoted message said:

I'm looking to build a
set of wheels for heavy commuting. Already decided on Campy

Record

Quoted message said:

Quoted message said:

hubs, 36 hole.

Quoted message said:

Now... what rims.... the open pro, the CXP-33, or other

suggestions?

Quoted message said:

Quoted message said:

Part of the reason the CXP-33 can be built into a stronger

wheel is that it

Quoted message said:

is heavier (480g) than the Open Pro (425g). All else being

equal, a heavier

Quoted message said:

rim will permit higher spoke tension and make for a more

durable wheel. Of

Quoted message said:

course, all else is not equal between those two rims, but the

edge would go

Quoted message said:

to the CXP-33.

I agree with Paul that offset and off-center rims are a good

idea, but I

Quoted message said:

would consider the Velocity Aerohead too light (405g) for heavy

commuting.

Quoted message said:

Rivendell sells a 700C, offset/off-center Velocity Synergy rim

in 36 hole.

Quoted message said:

I'm not sure of the exact quoted weight but it's closer to

500g, and it's

Quoted message said:

wider which would more easily allow wider commuting tires.

http://www.rivendellbicycles.com/webalog/wheels/18094.html

For off-center rear rims, there's also the

similarly-constructed Bontrager

Quoted message said:

Fairlane and Ritchey Trekking.

Other appropriate rims would include the Velocity Dyad, Sun

CR-18, and Alex

Quoted message said:

Adventurer.

Use butted spokes.

I commute to work every day on a Velocity Aeorhead OC 32 spoke
rear wheel (14/15 spokes -- 23mm tires), about 110 Kgf, and it is
as true as the day I built it. I weigh 208 and frequently ride
with a back pack and my route home (depending on which one) may
include grades up to 20 percent and rough roads. The wheel sees
a lot of abuse. With that said, however, I trashed a 36 hole
Velocity Aeorhead OC on the same bike hitting a giant pot hole
(night commuting). I suspect the impact would have done less
damage to an MA2 or similar 500 gram-ish rim -- or any wheel with
a wider tire. The bottom line for me is that I like to ride home
through the hills on the way home, and a lighter set of commuting
wheels has always been to my taste. The Velocity may be too
light to withstand significant impacts, but it is certainly
strong enough to withstand spoke tension and ordinary impacts
encountered on paved-but-rough roads. It may also be the case
that a 25mm tire on the Velocity could have avoided the damage,
or a better headlight. -- Jay Beattie.

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

Anyone have an opinion on relative rim strength? (all other things on
the wheel being equal)
The Mavic Open Pro seems to be the standard... but someone made an
argument that the CXP-33, with its triangular shape, is a stronger rim.
I don't know anything about physics, so ... the argument makes sense
to me... but, figured I'd see what other people's experiences are.
I've ridden open pros, and been fine with them. I'm looking to build a
set of wheels for heavy commuting. Already decided on Campy Record
hubs, 36 hole.
Now... what rims.... the open pro, the CXP-33, or other suggestions?

What you are looking for is the strongest wheel. To get the strongest wheel
you need to get the spoke tension as high as possible. Rims that allow the
highest tension are usually V shaped rims. You would be better off if you
could find a set of CXP30's.
-------------
Alex

Velo Psycho said:

Anyone have an opinion on relative rim strength? (all other things on
the wheel being equal)

The Mavic Open Pro seems to be the standard... but someone made an
argument that the CXP-33, with its triangular shape, is a stronger rim.

Absolutely. That is why these triangular rims are used on extremely low
spoke-count wheels. They need a rim that is as strong as possible to stay
roughly round in between the spokes. The CXP- is not a great rim, with
its bogus eyelets, but I use them since they are strong. They are also
easy to keep true.

Quoted message said:

to me... but, figured I'd see what other people's experiences are. I've
ridden open pros, and been fine with them. I'm looking to build a set
of wheels for heavy commuting. Already decided on Campy Record hubs, 36
hole.

Unless you are quite heavy or the roads you commute on are really awful,
these should be fine.

--

David L. Johnson

__o | And though I have the gift of prophecy, and understand all
_`\(,_ | mysteries, and all knowledge; and though I have all faith, so
(_)/ (_) | that I could remove mountains, and have not charity, I am
nothing. [1 Corinth. 13:2]

Ronald van Tol said:

Quoted message said:

I have had no spoke pull through on the Velocity
rims even though they have no eyelets.

Did you use washers on the nipples?

No, I never used washers.

David L. Johnson said:

Absolutely. That is why these triangular rims are used on extremely low
spoke-count wheels. They need a rim that is as strong as possible to stay
roughly round in between the spokes. The CXP- is not a great rim, with
its bogus eyelets, but I use them since they are strong. They are also
easy to keep true.

I'm confused. I thought that a V shaped rim was stiffer. The longer
the V the stiffer. If you take a rim that's standing on edge and
press down on it, you can feel that the V shaped rim is more difficult
to bend. With fewer spokes, a rim that bends less is needed because
there are wider spaces between the spokes and the rim needs to flex
less between spokes.

Is stiffer stronger?

Paul Kopit said:

I'm confused. I thought that a V shaped rim was stiffer. The longer
the V the stiffer. If you take a rim that's standing on edge and
press down on it, you can feel that the V shaped rim is more difficult
to bend. With fewer spokes, a rim that bends less is needed because
there are wider spaces between the spokes and the rim needs to flex
less between spokes.

Is stiffer stronger?

In this context, yes.

--

David L. Johnson

__o | When you are up to your ass in alligators, it's hard to remember
_`\(,_ | that your initial objective was to drain the swamp. -- LBJ
(_)/ (_) |

Velo Psycho said:

Anyone have an opinion on relative rim strength? (all other things on
the wheel being equal)

The Mavic Open Pro seems to be the standard... but someone made an
argument that the CXP-33, with its triangular shape, is a stronger rim.
I don't know anything about physics, so ... the argument makes sense
to me... but, figured I'd see what other people's experiences are.
I've ridden open pros, and been fine with them. I'm looking to build a
set of wheels for heavy commuting. Already decided on Campy Record
hubs, 36 hole.

Now... what rims.... the open pro, the CXP-33, or other suggestions?

Standard?

We switched from Campagnolo Montreal to the offset Velocity
Aerohead OC for our standard clincher rim a couple of years
ago (when Campagnolo dropped their rim program)

IMHO that rim builds a superior wheel as the tension is
nearly even left to right. Costs no more than the old
fashioned symmetric rims we used to use before modern 9/10 hubs!

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

David L. Johnson said:

Paul Kopit said:

I'm confused. I thought that a V shaped rim was stiffer. The longer
the V the stiffer. If you take a rim that's standing on edge and
press down on it, you can feel that the V shaped rim is more difficult
to bend. With fewer spokes, a rim that bends less is needed because
there are wider spaces between the spokes and the rim needs to flex
less between spokes.

Is stiffer stronger?

In this context, yes.

i'd be careful with that statement. cookies are stiff, but not very
strong. stiffness & strength are different. stiffness is the slope of
the stress/strain line. strength is how long that line will extend
before it becomes non-linear. easily confusing.

jim beam said:

i'd be careful with that statement. cookies are stiff, but not very
strong....

Someone must not be familiar with "soft-bake" cookies, as they are
neither stiff nor strong.

--
Tom Sherman - Earth

jim beam said:

Quoted message said:

Quoted message said:

Is stiffer stronger?

In this context, yes.

i'd be careful with that statement. cookies are stiff, but not very
strong. stiffness & strength are different. stiffness is the slope of
the stress/strain line. strength is how long that line will extend
before it becomes non-linear. easily confusing.

Well, a thicker cookie would be stronger as well as stiffer. Since we're
talking about the same materials for both box-section and "aero" rims, I'd
be willing to bet that the v-shaped rim is both stiffer and stronger.
Heavier, too, of course. But my Mavic v-shaped rims have stayed round
over time much more reliably than the MA-2s (two of which did not
even start out round).

--

David L. Johnson

__o | It is a scientifically proven fact that a mid life crisis can
_`\(,_ | only be cured by something racy and Italian. Bianchis and
(_)/ (_) | Colnagos are a lot cheaper than Maserattis and Ferraris. --
Glenn Davies

In article <[email hidden]>, Velo

Psycho said:

Anyone have an opinion on relative rim strength? (all other things on
the wheel being equal)

The Mavic Open Pro seems to be the standard... but someone made an
argument that the CXP-33, with its triangular shape, is a stronger rim.
I don't know anything about physics, so ... the argument makes sense
to me... but, figured I'd see what other people's experiences are.
I've ridden open pros, and been fine with them. I'm looking to build a
set of wheels for heavy commuting. Already decided on Campy Record
hubs, 36 hole.

Now... what rims.... the open pro, the CXP-33, or other suggestions?

I have a CXP-33 on the front of my touring/commuting bike (36H) and
it's very strong. Had toured loaded with panniers in the front and no
problems and best of all, I got the rim off eBay for $15 new. I can't
complain about that!

David.

"Paul Kopit" <[email hidden]> wrote in message

Quoted message said:

The Velocity Aerohead OC offset and off center permits even more
tension on the non drive side and, in my opinion, this will permit the
strongest wheel. I have had no spoke pull through on the Velocity
rims even though they have no eyelets.

I have two questions about these non symmetric rims like the Aerohead OC and
Bontrager:

1) Is this design more prone to failure because it the rim is less stiff on
the side further from the spoke heads, do these rims tend to bend toward or
fail on the left side easier?

2) If I were really fast would the profile of this rim act as an airfoil and
suck the wheel ever so slightly to the left?

I suspect that the answer in both cases is yes but I have no idea if it
makes any practical difference in either case.

Dave
Noblesville Indiana

Dave Reckoning said:

"Paul Kopit" <[email hidden]> wrote in message

Quoted message said:

The Velocity Aerohead OC offset and off center permits even more
tension on the non drive side and, in my opinion, this will permit the
strongest wheel. I have had no spoke pull through on the Velocity
rims even though they have no eyelets.

I have two questions about these non symmetric rims like the Aerohead OC and
Bontrager:

1) Is this design more prone to failure because it the rim is less stiff on
the side further from the spoke heads, do these rims tend to bend toward or
fail on the left side easier?

2) If I were really fast would the profile of this rim act as an airfoil and
suck the wheel ever so slightly to the left?

I suspect that the answer in both cases is yes but I have no idea if it
makes any practical difference in either case.

It depends on which direction in which hemisphere you are riding in.
Google "coriolis effect". 😉

--
Tom Sherman – Earth