Wheels for 700lb guy?

Pete Biggs wrote:

wrote:

Presumably I had uneven spoke tension that I should have kept an eye
on, and I got cracks from that, causing the wheel to go out of true.
Does that sound right?

Cracks around the spoke holes sounds like excessive spoke tension.

--which is only a chronic issue with Mavic rims from the last ~20
years. "Excessive" spoke tension therefore can be evaluated
alternatively as "substandard" rim structure.

I can say that recent Mavic rims have failed for me at spoke tensions
where lighter rims from other makers have held up fine.

Chalo

On Nov 16, 10:49*pm, landotter wrote:
On Nov 16, 9:56*pm, wrote:

Alex DM18s are a good choice for a clyde. It's got even more meat than
the Mavic. Less than $20. ERD is close enough to the 604 I found for
the Mavics for you do tape 'em up and do a direct swap. You'll need to
emery paper the joints as they aren't welded, if you want smooth
braking.

Well that sounds like maybe a good combo of cheap solution and an
intro to wheel building. *If I mess it up, not such a big deal for
$20. *It does look like a pretty hefty cross section too.

You'll have to double check the ERD for sure, but if it's within a
couple mms--indeed, just tape the rims together, making sure that the
"handedness" of the spoke holes is correct, and swap the spokes one by
one. Use an electric driver from the inside to do this. A flat head
will do, or a philips bit with most of two fins ground off works as
well. If you don't have a truing stand, like most of us, do remember
to set your brake pads very carefully and closely before you do this--
and you can use your bike as a truing stand.

The Alex is a good strong rim--it's not machined and it's not welded,
so it will take emery paper for a minute or three on the joint. It
should solve your problem if built right and tensioned well. My last
rerimming I did with some has a couple thousand miles on 'em with no
touch ups needed. I've hauled groceries, ice biked--you name it, DM18s
is strong stuff. Don't let the non-Eurosnob price tag fool you.

I'll cast another vote for Alex, but I say spring for another 5 bucks
and get the Adventurer, which has eyeleted spoke holes.

wrote:

landotter wrote:

Alex DM18s are a good choice for a clyde. It's got even more meat than
the Mavic. Less than $20. ERD is close enough to the 604 I found for
the Mavics for you do tape 'em up and do a direct swap. You'll need to
emery paper the joints as they aren't welded, if you want smooth
braking.

Well that sounds like maybe a good combo of cheap solution and an
intro to wheel building. If I mess it up, not such a big deal for
$20. It does look like a pretty hefty cross section too.

After trying a variety of spoke types and gauges we switched to a 48
spoke rim and haven't had any more problems.

That sounds like the correct long term solution for me. I'm going to
take a hard look at tandem wheels. Rebuilding with a cheap rim is
probably better given my grad school budget at the moment, but more
spokes sound like a good idea as soon as I can.

I second landotter's recommendation of the Alex DM18. It's a sane
cross-section, heavy enough for the job, made of good strong 6061-T6
alloy, and cheap to buy. It's what most people should have on their
road bikes if they don't like to repair their wheels and don't want to
spend a lot of money on them.

If you intend to run tires at least 30mm wide (and you should do so),
the Sun Rhyno Lite 700c is another good candidate. It weighs in the
same range as the DM18, but it has a larger cross-section (therefore
more stiffness and better load sharing among spokes).

Both of the above rims are made from much more ductile and less crack-
prone than anything Mavic has made in a long time.

If you want to use narrow tires of less than 28mm width, the Velocity
Deep-V is a more expensive but very strong rim, especially when laced
with 36 or more spokes. It's pretty lightweight, too-- just 520g
claimed, though all rims vary from one specimen to the next.

Most of my bikes have 48 spoke wheels. (I weigh about 350 lbs. at the
moment, but I have weighed as much as 400 lbs. I am 6'8" tall.) But
most of my bikes have rims that are no longer available. To
complicate matters, most of today's strongest rims come only in 32 and
36 hole versions. So it's no longer the undisputed best idea to use
48 spokes if you want the strongest possible wheel. You have to weigh
your priorities against the available options. Where 48 spokes may
still offer the best weight bearing and the greatest future
serviceability, some 36 spoke wheels may offer better stiffness and
less frequent maintenance simply because the choice of rims is
better.

For the ultimate in strength, but a width that makes it incompatible
with most road bikes, the Kris Holm 29" (700c) mountain unicycle rim
is currently without peer in its rim diameter. It's 38mm wide and
weighs in the neighborhood of 900g. It comes only in 32 and 36 hole
variants.

http://www.unicycle.com/shopping/shopexd.asp?id=805

I don't think that will be necessary for you. I think that a good
wheel build with 36 14ga. or 14/15ga. spokes and Alex DM18 rims should
do the trick. If your riding habits or road conditions are
particularly harsh and that does not solve your problems, it is at
least the cheapest and most effective next step along your way. 300
pounds is really not all that much in the grand scheme of things. 700
pounds, well... that's another matter. Check back in with me in that
case. I have some ideas.

I encourage you to read _The Bicycle Wheel_ by Jobst Brandt, or
http://www.sheldonbrown.com/wheelbuild.html, or b oth, and try your
hand at building your own wheels. If your above average mass, like
mine, is a permanent condition rather than a weight fluctuation, you
will do yourself a service in the long term by building and
maintaining your own wheels.

Chalo

On Nov 17, 1:33*am, Hank wrote:
On Nov 16, 10:49*pm, landotter wrote:



On Nov 16, 9:56*pm, wrote:

Alex DM18s are a good choice for a clyde. It's got even more meat than
the Mavic. Less than $20. ERD is close enough to the 604 I found for
the Mavics for you do tape 'em up and do a direct swap. You'll need to
emery paper the joints as they aren't welded, if you want smooth
braking.

Well that sounds like maybe a good combo of cheap solution and an
intro to wheel building. *If I mess it up, not such a big deal for
$20. *It does look like a pretty hefty cross section too.

You'll have to double check the ERD for sure, but if it's within a
couple mms--indeed, just tape the rims together, making sure that the
"handedness" of the spoke holes is correct, and swap the spokes one by
one. Use an electric driver from the inside to do this. A flat head
will do, or a philips bit with most of two fins ground off works as
well. If you don't have a truing stand, like most of us, do remember
to set your brake pads very carefully and closely before you do this--
and you can use your bike as a truing stand.

The Alex is a good strong rim--it's not machined and it's not welded,
so it will take emery paper for a minute or three on the joint. It
should solve your problem if built right and tensioned well. My last
rerimming I did with some has a couple thousand miles on 'em with no
touch ups needed. I've hauled groceries, ice biked--you name it, DM18s
is strong stuff. Don't let the non-Eurosnob price tag fool you.

I'll cast another vote for Alex, but I say spring for another 5 bucks
and get the Adventurer, which has eyeleted spoke holes.

DM18 in 700c *is* eyeleted.* The Adventurer is powder coated and has
machined walls and handsomer for sure, but the ERD ain't right.

On Nov 17, 12:09*am, landotter wrote:
On Nov 17, 1:33*am, Hank wrote:



On Nov 16, 10:49*pm, landotter wrote:

On Nov 16, 9:56*pm, wrote:

Alex DM18s are a good choice for a clyde. It's got even more meat than
the Mavic. Less than $20. ERD is close enough to the 604 I found for
the Mavics for you do tape 'em up and do a direct swap. You'll need to
emery paper the joints as they aren't welded, if you want smooth
braking.

Well that sounds like maybe a good combo of cheap solution and an
intro to wheel building. *If I mess it up, not such a big deal for
$20. *It does look like a pretty hefty cross section too.

You'll have to double check the ERD for sure, but if it's within a
couple mms--indeed, just tape the rims together, making sure that the
"handedness" of the spoke holes is correct, and swap the spokes one by
one. Use an electric driver from the inside to do this. A flat head
will do, or a philips bit with most of two fins ground off works as
well. If you don't have a truing stand, like most of us, do remember
to set your brake pads very carefully and closely before you do this--
and you can use your bike as a truing stand.

The Alex is a good strong rim--it's not machined and it's not welded,
so it will take emery paper for a minute or three on the joint. It
should solve your problem if built right and tensioned well. My last
rerimming I did with some has a couple thousand miles on 'em with no
touch ups needed. I've hauled groceries, ice biked--you name it, DM18s
is strong stuff. Don't let the non-Eurosnob price tag fool you.

I'll cast another vote for Alex, but I say spring for another 5 bucks
and get the Adventurer, which has eyeleted spoke holes.

DM18 in 700c *is* eyeleted.* The Adventurer is powder coated and has
machined walls and handsomer for sure, but the ERD ain't right.

ERD for A719 is 600.5 (per Spocalc)
Adventurer is 603.1
DM18 is 606.4 (per alexrims.com)

I'd say you're much more likely to be able to do the swap with the
Adventurer.

I second landotter's recommendation of the Alex DM18. It's a sane
cross-section, heavy enough for the job, made of good strong 6061-T6
alloy, and cheap to buy. It's what most people should have on their
road bikes if they don't like to repair their wheels and don't want to
spend a lot of money on them.

Got some in my future then.


*700
pounds, well... that's another matter. *Check back in with me in that
case. *I have some ideas.

Maybe someday with the full load of groceries and the dog ;-)

I encourage you to read _The Bicycle Wheel_ by Jobst Brandt, orhttp://www..sheldonbrown.com/wheelbuild.html, or b oth, and try your
hand at building your own wheels. *If your above average mass, like
mine, is a permanent condition rather than a weight fluctuation,

It is. I'm a big guy, dad was a big guy, I've been right around 300
for at least six years now, with practically no gain or loss. I was a
little lower in college but *that* was the fluctuation ;-)

you
will do yourself a service in the long term by building and
maintaining your own wheels.

I'm a handy guy overall, so that appeals to me (as does some of your
custom machined stuff, by the way ! ) I'm a little low on time at the
moment, so the idea of the quick swap to the DM18 as people have
described is pretty attractive, rather than lacing a new wheel from
scratch, but I see the point to doing the work myself.

I've spent way too much on broken wheels...

Thanks for the advice, everyone, I think I'm going to go with the
DM18's and do the taped swap with the existing spokes and hub; that
sounds like the best and cheapest way to get me going again right now,
and I'll learn to build from scratch by the next time.

Thanks a lot, the existence of $20 decent rims makes me a lot more
comfortable re-rimming my wheel somehow ;-)

Dan

On Nov 16, 5:42*pm, wrote:
Ok, I don't weigh 700 pounds. *I weigh a solid 300. I don't care about
the weight of my rims, I care only about strength and fatigue
performance. * I have a short, flat, bike ride to work every day.

I bought some Mavic A719 36 hole wheels for my bike and kept an eye
(not good enough, apparently) on them to see if they were still
running true. *They ran true for a long time but when did go out, I
already had fatigue cracks around several spokes and I need a new rear
wheel again.

Presumably I had uneven spoke tension that I should have kept an eye
on, and I got cracks from that, causing the wheel to go out of true.
Does that sound right?

There's nothing rough or hard about my ride...the big sin I'm
committing, if any, is not paying enough attention to my spokes on a
regular basis, but I'd really like to come up with a wheel
configuration where I didn't have to ping each spoke every morning and
sit right down there in the driveway with the spoke wrench if
something's off.

I used this subject line because I find plenty of "I'm 250lb and
touring with 50lb of gear and my Mavic A719's are fine" kind of posts
on the internet, but what I want to know is "I'm 300 pounds and want
wheels I can ignore at least a little in the interest of just getting
into work." *I'm not saying I'm not going to true the things, I'm just
saying I want to do it on Saturday and I don't want eight miles of out-
of-true ride to be an absolute death knell for my wheels

Is that a ridiculous hope? *Is the 300-lb fat-guy wheel **with a
margin of error** a pipe dream, at least in a price range under
several hundred bucks? *Hopefully I'm not offending everyone by even
asking ;-)

I've gone through a couple decent sets of rims with fatigue cracks
around the spoke holes (yes, both were eyeletted), and I suppose it's
just my fault for being cavalier about maintenance *but it seems like
cracking rims on an 8 mile round trip, flat, minimally bumpy ride
means I'm right up at the capacity limit for the wheel, and I want
something that will do more. *I probably can't have it, but I figured
I'd ask.

-Dan Zimmerman

Set of these-

http://www.velocityusa.com/default.asp?contentID=584

36 front, 48 rear. Good enough for a tandem, good enough for you.
shimano tandem hubs modified for your frame or Phil Wood.

On Sun, 16 Nov 2008 23:02:41 -0800, Chalo wrote:

Pete Biggs wrote:

wrote:

Presumably I had uneven spoke tension that I should have kept an eye
on, and I got cracks from that, causing the wheel to go out of true.
Does that sound right?

Cracks around the spoke holes sounds like excessive spoke tension.

--which is only a chronic issue with Mavic rims from the last ~20 years.
"Excessive" spoke tension therefore can be evaluated alternatively as
"substandard" rim structure.

not if the spoke tension is to spec. spoke tension "as high as the rim
can bear" is not only wrong, it's borne of a fundamental misunderstanding
of the rim's function in a wheel.





I can say that recent Mavic rims have failed for me at spoke tensions
where lighter rims from other makers have held up fine.

but that is not the same as the manufacturers spec. applying the cylinder
head bolt spec from a '57 chevy to a 2007 honda civic isn't a useful
comparison. with rims, it's not overall weight, but where the material is
distributed that matters.

On Mon, 17 Nov 2008 01:43:12 +0100, Pete Biggs wrote:

wrote:
Ok, I don't weigh 700 pounds. I weigh a solid 300. I don't care about
the weight of my rims, I care only about strength and fatigue
performance. I have a short, flat, bike ride to work every day.

I bought some Mavic A719 36 hole wheels for my bike and kept an eye
(not good enough, apparently) on them to see if they were still running
true. They ran true for a long time but when did go out, I already had
fatigue cracks around several spokes and I need a new rear wheel again.

Presumably I had uneven spoke tension that I should have kept an eye
on, and I got cracks from that, causing the wheel to go out of true.
Does that sound right?

Cracks around the spoke holes sounds like excessive spoke tension.

~PB


indeed - that's why manufacturers have spoke tension specifications for
their rims.

On Sun, 16 Nov 2008 16:42:33 -0800, n3ox.dan wrote:

Ok, I don't weigh 700 pounds. I weigh a solid 300. I don't care about
the weight of my rims, I care only about strength and fatigue
performance. I have a short, flat, bike ride to work every day.

I bought some Mavic A719 36 hole wheels for my bike and kept an eye (not
good enough, apparently) on them to see if they were still running true.
They ran true for a long time but when did go out, I already had
fatigue cracks around several spokes and I need a new rear wheel again.

Presumably I had uneven spoke tension that I should have kept an eye on,
and I got cracks from that, causing the wheel to go out of true. Does
that sound right?

There's nothing rough or hard about my ride...the big sin I'm
committing, if any, is not paying enough attention to my spokes on a
regular basis, but I'd really like to come up with a wheel configuration
where I didn't have to ping each spoke every morning and sit right down
there in the driveway with the spoke wrench if something's off.

I used this subject line because I find plenty of "I'm 250lb and touring
with 50lb of gear and my Mavic A719's are fine" kind of posts on the
internet, but what I want to know is "I'm 300 pounds and want wheels I
can ignore at least a little in the interest of just getting into work."
I'm not saying I'm not going to true the things, I'm just saying I want
to do it on Saturday and I don't want eight miles of out- of-true ride
to be an absolute death knell for my wheels

Is that a ridiculous hope? Is the 300-lb fat-guy wheel **with a margin
of error** a pipe dream, at least in a price range under several hundred
bucks? Hopefully I'm not offending everyone by even asking ;-)

I've gone through a couple decent sets of rims with fatigue cracks
around the spoke holes (yes, both were eyeletted),

excess spoke tension - pure and simple. use a tensiometer and build to
the manufacturer's spoke tension spec.



and I suppose it's
just my fault for being cavalier about maintenance but it seems like
cracking rims on an 8 mile round trip, flat, minimally bumpy ride means
I'm right up at the capacity limit for the wheel, and I want something
that will do more. I probably can't have it, but I figured I'd ask.



use tandem wheels. and deep section rims distort less at the loading zone
and thus do not lose as much spoke tension. thus there is less fatigue
cycling and less spoke loosening.

again, observe the rim manufacturer's spoke tension spec.