Front Wheel Stiffness: 28 vs. 32 spokes?

Plan on building up a set of lightweight training wheels, and normally
I would use a 32-hole front hub with DT Revolution spokes. I can get
a good deal on 28-hole hub, but I'm hesitant to use it - not sure if
he wheel will be stiff enough. How much difference in stiffness
can I expect between a 28 and a 32 spoke wheel (DT Revo spokes,
Open-Pro rims)?

Thanks in advance,
Steve T

SteveT wrote:
Plan on building up a set of lightweight training wheels, and normally
I would use a 32-hole front hub with DT Revolution spokes. I can get
a good deal on 28-hole hub, but I'm hesitant to use it - not sure if
he wheel will be stiff enough. How much difference in stiffness
can I expect between a 28 and a 32 spoke wheel (DT Revo spokes,
Open-Pro rims)?

32 spokes is almost always a better choice than 28 spokes. However,
that's a matter of structural integrity and durability, and not a
stiffness issue. The bracing angle of a front hub us usually wide
enough that any wheel strong enough to hold up to any given use will
neccessarily be plenty stiff for that use.

If you use thicker spokes on the lower spoke count wheel, you'll
increase its stiffness over what you'd get from DT Revolutions. In
this case, even 15/16ga. spokes qualify as "thicker". DT Competitions
are also way less expensive and come with brass nipples, which are
superior to the aluminum ones supplied with DT Revs.

If you haven't already bought your rim, I recommend not using a Mavic
rim. I think it's difficult to buy worse rims for the money than
Mavics anymore. If cost-effectiveness and durability matter to you,
check out Rigida, Alex, and Sun rims-- which have proven to me to offer
consistently better quality than Mavic rims at a fraction of the cost.
Ambrosio and Fir rims have a good reputation for quality, and they cost
much less than Mavics as well.

SteveT wrote:
Plan on building up a set of lightweight training wheels, and normally
I would use a 32-hole front hub with DT Revolution spokes. I can get
a good deal on 28-hole hub, but I'm hesitant to use it - not sure if
he wheel will be stiff enough. How much difference in stiffness
can I expect between a 28 and a 32 spoke wheel (DT Revo spokes,
Open-Pro rims)?

Thanks in advance,
Steve T


how heavy are you? most builders would not recommend going too skinny
on the spokes with a low count wheel and a heavy rider.

to perform a real rough comparison between the two wheels, add up the
total cross sectional area of your total spoke count. area of 1.5mm
diameter x 32 vs. the same for 28. then compare it with 28 spokes at
1.8mm diameter or some other size as you fancy. 28 x 1.8mm spokes will
be stiffer than 32 x 1.5mm. i have a 24 x 2.0mm spoke front wheel and
it's plenty stiff under my #205.

SteveT wrote:
How much difference in stiffness
can I expect between a 28 and a 32 spoke wheel (DT Revo spokes,
Open-Pro rims)?

Too little to notice. In a test, reducing the spoke stiffness by half
only resulted in an 11% reduction in lateral wheel stiffness. See #7:
http://www.sheldonbrown.com/rinard/wheel/

But the issue isn't stiffness, but rather fatigue strength. If you are
a lightweight you should be fine... 28 spoke front wheels are certainly
common these days. That isn't to say that 32 or 36 wouldn't be better.
For an "everyday" wheel I'd opt for greater durability... and lower
cost.

What do you intend to use this wheel for? The wheel you have described
is not aero, so it would not be the best choice for racing. If you
wanted a fast wheel, I'd advise a deep (30mm) aero rim and butted oval
spokes... it need not cost any more than Open Pro and Revos.

SteveT wrote:
Plan on building up a set of lightweight training wheels

Why light weight 'training' wheel?

, and normally
I would use a 32-hole front hub with DT Revolution spokes. I can get
a good deal on 28-hole hub, but I'm hesitant to use it - not sure if
he wheel will be stiff enough. How much difference in stiffness
can I expect between a 28 and a 32 spoke wheel (DT Revo spokes,
Open-Pro rims)?

Probably not enough to notice but just use `14/15 spokes on that 28,
laced 2 cross and you'll be fine. I see no need for Revs on any
'training' wheel.

Thanks in advance,
Steve T

Chalo wrote:
SteveT wrote:
Plan on building up a set of lightweight training wheels, and normally
I would use a 32-hole front hub with DT Revolution spokes. I can get
a good deal on 28-hole hub, but I'm hesitant to use it - not sure if
he wheel will be stiff enough. How much difference in stiffness
can I expect between a 28 and a 32 spoke wheel (DT Revo spokes,
Open-Pro rims)?

32 spokes is almost always a better choice than 28 spokes. However,
that's a matter of structural integrity and durability, and not a
stiffness issue. The bracing angle of a front hub us usually wide
enough that any wheel strong enough to hold up to any given use will
neccessarily be plenty stiff for that use.

If you use thicker spokes on the lower spoke count wheel, you'll
increase its stiffness over what you'd get from DT Revolutions. In
this case, even 15/16ga. spokes qualify as "thicker". DT Competitions
are also way less expensive and come with brass nipples, which are
superior to the aluminum ones supplied with DT Revs.

If you haven't already bought your rim, I recommend not using a Mavic
rim. I think it's difficult to buy worse rims for the money than
Mavics anymore. If cost-effectiveness and durability matter to you,
check out Rigida, Alex, and Sun rims-- which have proven to me to offer
consistently better quality than Mavic rims at a fraction of the cost.
Ambrosio and Fir rims have a good reputation for quality, and they cost
much less than Mavics as well.

Interesting choices. Of the ones you mention, only a few are available
in the US. Sun and Alex are really poor rims, IMO, after building some
wheels with them. Ambrosio as well. Fir used to be great but I don't
think ZAR is importing them any more. Velocity is the one I recommend
and Open Pros, CXP-33s are not the horror story that I can see. We
build with 200 or so Mavic rims per year..

SteveT wrote:
Plan on building up a set of lightweight training wheels, and normally
I would use a 32-hole front hub with DT Revolution spokes. I can get
a good deal on 28-hole hub, but I'm hesitant to use it - not sure if
he wheel will be stiff enough.

http://www.damonrinard.com/wheel/

Light, training? --D-y

Qui si parla Campagnolo wrote:

Chalo wrote:

If you haven't already bought your rim, I recommend not using a Mavic
rim. I think it's difficult to buy worse rims for the money than
Mavics anymore. If cost-effectiveness and durability matter to you,
check out Rigida, Alex, and Sun rims-- which have proven to me to offer
consistently better quality than Mavic rims at a fraction of the cost.
Ambrosio and Fir rims have a good reputation for quality, and they cost
much less than Mavics as well.

Interesting choices. Of the ones you mention, only a few are available
in the US. Sun and Alex are really poor rims, IMO, after building some
wheels with them. Ambrosio as well. Fir used to be great but I don't
think ZAR is importing them any more. Velocity is the one I recommend
and Open Pros, CXP-33s are not the horror story that I can see. We
build with 200 or so Mavic rims per year..

I used to favor Mavic rims, and I was very happy with the Module 3,
Module 4, and M281 back when those were available. Every experience
I've had with a Mavic rim more recently than that has been a
disappointment. They are weaker than other comparable rims in several
different ways-- in my experience they are vulnerable to spoke bed,
rim joint, and sidewall failures. They are made from unusually weak
aluminum alloy.

OTOH, Alex rims have been a very pleasant surprise to me. I never
expected them to be great rims due to their low prices. I have used
their DM-24, DM-18, Adventurer, Supra RX, and X-101 in various
diameters. They have always built up without any complications and
they have seemed to require less truing and to support higher spoke
tensions than comparable rims, including those made by Sun.

Sun Rims have been a standby for me for many years. I have come to
appreciate their reliability and overall strength, and I love the
polished finish in which some of them have traditionally been
available. The Rhyno Lite and CR-18 have gotten most of my repeat
business, but I also like the Venus, Mammoth/BFR, and Big City.

Velocity rims seem OK to me, but I don't like their lack of eyelets (it
often imposes a lower practical tension limit than they would otherwise
have, and it can complicate maintenance truing) and I think most of
them look cheesy. They are also way more expensive than their level of
construction warrants IMO. They are $20 rims that cost $60. Like
Mavics, they are made from softer, weaker alloy (6106) than for example
Alex rims (6061). The use of this weak alloy gives them the benefit of
cleaner cosmetic finish at the expense of structural integrity-- a
/terrible/ bargain in my book.

Some of the most expensive Mavic rims are made from some alloy called
"Maxtal" for which they claim "30 percent stronger". If true, that's
30 percent stronger than the alloy that composes most of their rims--
which is about 25% weaker than good old 6061. It makes me wonder
whether "Maxtal" is their marketing-speak for the same 6061 alloy that
Alex are using to make rims that cost 1/4 as much.

As for Rigida rims, I have bought them in the aftermarket here in the
USA, and I like them. The ones I've used most are 48H 700c tandem rims
with double eyelets, superfically comparable to the Mavic T519/T520 and
A719. But while those particular Mavic rims have given me a great deal
of trouble, the Rigidas (which I have on three different bikes) have
been stone reliable.

Chalo Colina