How to true bladed spoked wheels

I've built and trued lots of regular wheels, but not the newer bladed spoke
wheels. I have a set of Bontager Race X-lites that, while they are true at
the moment, I'd like to know how to true them if and when they go out of
true.

Are there any online sites discussing this topic? Sheldon Brown doesn't
discuss these wheels specifically. I have heard that some manufacturers
include a "blade holding tool" with their wheels.

All help appreciated, and if you could email me directly I'd appreciate it
since my ISP seems to have trouble getting me NG access.

--

- - - John - - -
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~
John Baughman - Ohio State, Class of ' 72
P.O. Box 153
PLacida, FL 33946
www.FreeWheels.itgo.com
Mo-Town Forever!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~

John Baughman wrote:

I've built and trued lots of regular wheels, but not the newer bladed spoke
wheels. I have a set of Bontager Race X-lites that, while they are true at
the moment, I'd like to know how to true them if and when they go out of
true.

Are there any online sites discussing this topic? Sheldon Brown doesn't
discuss these wheels specifically. I have heard that some manufacturers
include a "blade holding tool" with their wheels.

Pretty much the same as normal. Spokes don't (or shouldn't) rotate when
being trued - only the nipples do. An advantage of bladed spokes is
that you can *see* if they get twisted and make sure you unwind them
before you're finished. Some lubricant on the nipples will help.

anonymous writes:

I've built and trued lots of regular wheels, but not the newer
bladed spoke wheels. I have a set of Bontrager Race X-lites that,
while they are true at the moment, I'd like to know how to true
them if and when they go out of true.

Are there any online sites discussing this topic? Sheldon Brown
doesn't discuss these wheels specifically. I have heard that some
manufacturers include a "blade holding tool" with their wheels.

Pretty much the same as normal. Spokes don't (or shouldn't) rotate
when being trued - only the nipples do. An advantage of bladed
spokes is that you can *see* if they get twisted and make sure you
unwind them before you're finished. Some lubricant on the nipples
will help.

What do you mean by "shouldn't" for spoke twist. Flat spokes have so
little torsional resistance that they twist like leaves in the wind.
Not only that, but they twist off if turned far enough. Torsional
stiffness varies as the 4th power of diameter. You lose fast and that
is why even 1.5mm diameter spokes easily twist off.

The proper way to tighten such spokes is to unload them at the moment
their nipples are turned. This can be done in a wheel truing machine
by applying a radial force on the rim with a pneumatic piston or
manually by pulling the rim toward the side of the spoke in question.

The best way is to not use such wheels.

Jobst Brandt

In article ,
says...

The proper way to tighten such spokes is to unload them at the moment
their nipples are turned. This can be done in a wheel truing machine
by applying a radial force on the rim with a pneumatic piston or
manually by pulling the rim toward the side of the spoke in question.

I've never done this, so I have to ask. Can't you just hold the spoke
on the flats to keep it from turning?
----------------
Alex

Jobst Brandt wrote:
The proper way to tighten such spokes is to unload them at the moment
their nipples are turned. This can be done in a wheel truing machine
by applying a radial force on the rim with a pneumatic piston or
manually by pulling the rim toward the side of the spoke in question.

Hm. Great but not easy to do at home without a fixed truing stand.
Can one use some marking on the spokes to see the twist? For example,
paint a strip along all the spoke with a white correction fluid.
And check that it does not turn into a nice winding spiral.

The best way is to not use such wheels.

Why not get 100g of weight savings with no loss in reliability?

Konstantin.

Alex Rodriguez writes:

The proper way to tighten such spokes is to unload them at the
moment their nipples are turned. This can be done in a wheel
truing machine by applying a radial force on the rim with a
pneumatic piston or manually by pulling the rim toward the side of
the spoke in question.

I've never done this, so I have to ask. Can't you just hold the
spoke on the flats to keep it from turning?

Yes, but you don't do it without damaging the spoke. Torsional
stiffness of the spoke is weak all the way into the transition to the
round part. Therefore, the transition, that starts flat and becomes
round, beyond the wrench that is on the flat part is as weak as the
rest of the flat part. Even though the affected length is short and
may not reveal any twist, it is yielding. This is then the newest
point of residual high stress. The weakest cross section is in the
flat part and that is the only place it can be clamped.

Jobst Brandt

"John Baughman" wrote in message
...
I've built and trued lots of regular wheels, but not the newer bladed
spoke
wheels. I have a set of Bontager Race X-lites that, while they are true at
the moment, I'd like to know how to true them if and when they go out of
true.

Are there any online sites discussing this topic? Sheldon Brown doesn't
discuss these wheels specifically. I have heard that some manufacturers
include a "blade holding tool" with their wheels.

All help appreciated, and if you could email me directly I'd appreciate it
since my ISP seems to have trouble getting me NG access.

--
One of the mechanics I worked with cut a small slot in a piece of 1/4" id
tubing to hold bladed spoke in place while truing the wheel. Seemed to
work.

Not having that tool, sometimes I'll wrap a pair of needlenose pliers in
shop rags and use them to keep the spoke straight. Ya gotta be real careful
here not to screw up the spoke... Stress risers and all that y'know.

Nice thing about truing bladed spokes is that you can see them twist and
counteract it.

Mike

Konstantin Shemyak writes:

The proper way to tighten such spokes is to unload them at the
moment their nipples are turned. This can be done in a wheel
truing machine by applying a radial force on the rim with a
pneumatic piston or manually by pulling the rim toward the side of
the spoke in question.

Hmm. Great but not easy to do at home without a fixed truing stand.
Can one use some marking on the spokes to see the twist? For
example, paint a strip along all the spoke with a white correction
fluid. And check that it does not turn into a nice winding spiral.

It's not twist per se that is interesting but to tighten a flat spoke
to effective tension is typically more than 1.5mm diameter spoke will
structurally withstand (it will rupture). Flat spokes are even weaker
and cannot be effectively tightened without going to yield.

The best way is to not use such wheels.

Why not get 100g of weight savings with no loss in reliability?

It's the "no loss in reliability" that you don't get easily, and that
is what we're talking about.

Jobst Brandt

Having built hundreds of these, a lubed nipple and hand pressure usually
nets 1/4-1/3 turnof twist which is then removed with the wrench, which is
good practice on round spoked wheels also (usually only 1/8 turn).
Tom

--
Bruni Bicycles
"Where art meets science"
brunibicycles.com
410.426.3420
Konstantin Shemyak wrote in message
...
Jobst Brandt wrote:
The proper way to tighten such spokes is to unload them at the moment
their nipples are turned. This can be done in a wheel truing machine
by applying a radial force on the rim with a pneumatic piston or
manually by pulling the rim toward the side of the spoke in question.

Hm. Great but not easy to do at home without a fixed truing stand.
Can one use some marking on the spokes to see the twist? For example,
paint a strip along all the spoke with a white correction fluid.
And check that it does not turn into a nice winding spiral.

The best way is to not use such wheels.

Why not get 100g of weight savings with no loss in reliability?

Konstantin.

Mike Shaw writes:

I've built and trued lots of regular wheels, but not the newer
bladed spoke wheels. I have a set of Bontrager Race X-lites that,
while they are true at the moment, I'd like to know how to true
them if and when they go out of true.

Are there any online sites discussing this topic? Sheldon Brown
doesn't discuss these wheels specifically. I have heard that some
manufacturers include a "blade holding tool" with their wheels.

All help appreciated, and if you could email me directly I'd
appreciate it since my ISP seems to have trouble getting me NG
access.

One of the mechanics I worked with cut a small slot in a piece of
1/4" id tubing to hold bladed spoke in place while truing the wheel.
Seemed to work.

Not having that tool, sometimes I'll wrap a pair of needle nose
pliers in shop rags and use them to keep the spoke straight. Ya
gotta be real careful here not to screw up the spoke... Stress
risers and all that y'know.

Nice thing about truing bladed spokes is that you can see them twist
and counteract it.

Not so nice as it seems. Most people using flat spokes also use fewer
than 32 spokes, meaning that the ones that are left must be tighter
than usual. When doing that, torque is high enough to damage the flat
spoke at its transition to its round cross section. It may look OK
but the spoke suffers plastic deformation at its end. This may not be
visible without a closer look because the shaft of the spoke is
straight. The permanent twist is at the transition, and that is not
readily visible. Out of sight, out of mind... but it will fail there
after fatiguing service.

Jobst Brandt