Spoke Tension of Rear Wheel

Gig Miller

This is my first wheel build. Using 700C Velocity Deep V rims and
Wheelsmith DB14 spokes.

I have been told by the folks at Velocity that they build their rear
wheels with spoke tension of 110-120KgF.

Something doesn't seem right. If I take the left side spokes to
110KgF, I have to tighten the right side spokes to appox. 180KgF in
order to get the dish right.

Does this sound right? Is 180KgF too much? If I take the right side
spokes to 120, the left side seems loose at about 72 KgF.

I'm using a Park Tool Tension Meter to get these values. Am I missing
something?

Thanks,

Greg



We build all of our wheels at the same spoke tension. Spoke tension
is measured in Kilograms of Force (KGF). We build the front wheel
between 105 – 115 KGF, and the rear between 110 – 120 KGF. I hope this
helps, let me know if you have any further questions.

A Muzi

Gig Miller wrote:
> This is my first wheel build. Using 700C Velocity Deep V rims and
> Wheelsmith DB14 spokes.
>
> I have been told by the folks at Velocity that they build their rear
> wheels with spoke tension of 110-120KgF.
>
> Something doesn't seem right. If I take the left side spokes to
> 110KgF, I have to tighten the right side spokes to appox. 180KgF in
> order to get the dish right.
>
> Does this sound right? Is 180KgF too much? If I take the right side
> spokes to 120, the left side seems loose at about 72 KgF.
>
> I'm using a Park Tool Tension Meter to get these values. Am I missing
> something?
>
> We build all of our wheels at the same spoke tension. Spoke tension
> is measured in Kilograms of Force (KGF). We build the front wheel
> between 105 – 115 KGF, and the rear between 110 – 120 KGF. I hope this
> helps, let me know if you have any further questions.

No conflict. The specified tension is for the right side! The left ends
at whatever is necessary to center the wheel with your hub spacing.
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

Werehatrack

On Sun, 11 May 2008 18:39:40 -0700 (PDT), Gig Miller
<thunderhawkk@yahoo.com> may have said:

>This is my first wheel build. Using 700C Velocity Deep V rims and
>Wheelsmith DB14 spokes.
>
>I have been told by the folks at Velocity that they build their rear
>wheels with spoke tension of 110-120KgF.
>
>Something doesn't seem right. If I take the left side spokes to
>110KgF, I have to tighten the right side spokes to appox. 180KgF in
>order to get the dish right.
>
>Does this sound right? Is 180KgF too much? If I take the right side
>spokes to 120, the left side seems loose at about 72 KgF.
>
>I'm using a Park Tool Tension Meter to get these values. Am I missing
>something?

Measure the tension of the drive side, not the non-drive, when
building. The non-drive will end up at a lower tension, and that's
normal. Tensioning the spokes beyond the rated maximum for the rim is
not recommended.

The accuracy of the Park tool is subject to fudge factors relating to
its handling of spoke thickness, if I recall correctly. Jobst Brandt
can elaborate on that issue.



--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

jim beam

Werehatrack wrote:
<snip for clarity>

>
> The accuracy of the Park tool is subject to fudge factors relating to
> its handling of spoke thickness, if I recall correctly. Jobst Brandt
> can elaborate on that issue.

he sure can - his elaboration is to declare it irrelevant to spoke
stiffness!

jim beam

Gig Miller wrote:
> This is my first wheel build. Using 700C Velocity Deep V rims and
> Wheelsmith DB14 spokes.
>
> I have been told by the folks at Velocity that they build their rear
> wheels with spoke tension of 110-120KgF.
>
> Something doesn't seem right. If I take the left side spokes to
> 110KgF, I have to tighten the right side spokes to appox. 180KgF in
> order to get the dish right.

that's too high. pay attention to the drive side spoke tension, not the
non-drive side. [if you want to check the math on this, i believe it's
now included in damon rinard's spokecalc.


>
> Does this sound right? Is 180KgF too much? If I take the right side
> spokes to 120, the left side seems loose at about 72 KgF.
>
> I'm using a Park Tool Tension Meter to get these values. Am I missing
> something?

tension differential is a function of hub spacing and therefore spoke
angle differential.


>
> Thanks,
>
> Greg
>
>
>
> We build all of our wheels at the same spoke tension. Spoke tension
> is measured in Kilograms of Force (KGF). We build the front wheel
> between 105 � 115 KGF, and the rear between 110 � 120 KGF. I hope this
> helps, let me know if you have any further questions.

Gig Miller

72KgF as indicated by the Park Tension Meter feels way too loose. I
question the precision, not accuracy of the Park meter. Anyone else
ever run into this with this meter? Has anyone ever set up their own
calibration apparatus and checked the values?

Greg


On May 11, 10:30 pm, A Muzi <a...@yellowjersey.org> wrote:
> Gig Miller wrote:
> > This is my first wheel build. Using 700C Velocity Deep V rims and
> > Wheelsmith DB14 spokes.
>
> > I have been told by the folks at Velocity that they build their rear
> > wheels with spoke tension of 110-120KgF.
>
> > Something doesn't seem right. If I take the left side spokes to
> > 110KgF, I have to tighten the right side spokes to appox. 180KgF in
> > order to get the dish right.
>
> > Does this sound right? Is 180KgF too much? If I take the right side
> > spokes to 120, the left side seems loose at about 72 KgF.
>
> > I'm using a Park Tool Tension Meter to get these values. Am I missing
> > something?
>
> > We build all of our wheels at the same spoke tension. Spoke tension
> > is measured in Kilograms of Force (KGF). We build the front wheel
> > between 105 – 115 KGF, and the rear between 110 – 120 KGF. I hope this
> > helps, let me know if you have any further questions.
>
> No conflict. The specified tension is for the right side! The left ends
> at whatever is necessary to center the wheel with your hub spacing.
> --
> Andrew Muzi
> <www.yellowjersey.org/>
> Open every day since 1 April, 1971
> ** Posted fromhttp://www.teranews.com**

jim beam

Gig Miller wrote:
> 72KgF as indicated by the Park Tension Meter feels way too loose. I
> question the precision, not accuracy of the Park meter. Anyone else
> ever run into this with this meter? Has anyone ever set up their own
> calibration apparatus and checked the values?

"feels way too loose"? if your judgment is better than the tensiometer,
why are you bothering with it at all?

more importantly, do you understand why dished wheels have a tension
differential? what are you hoping to achieve with higher tension?


>
> Greg
>
>
> On May 11, 10:30 pm, A Muzi <a...@yellowjersey.org> wrote:
>> Gig Miller wrote:
>>> This is my first wheel build. Using 700C Velocity Deep V rims and
>>> Wheelsmith DB14 spokes.
>>> I have been told by the folks at Velocity that they build their rear
>>> wheels with spoke tension of 110-120KgF.
>>> Something doesn't seem right. If I take the left side spokes to
>>> 110KgF, I have to tighten the right side spokes to appox. 180KgF in
>>> order to get the dish right.
>>> Does this sound right? Is 180KgF too much? If I take the right side
>>> spokes to 120, the left side seems loose at about 72 KgF.
>>> I'm using a Park Tool Tension Meter to get these values. Am I missing
>>> something?
>>> We build all of our wheels at the same spoke tension. Spoke tension
>>> is measured in Kilograms of Force (KGF). We build the front wheel
>>> between 105 � 115 KGF, and the rear between 110 � 120 KGF. I hope this
>>> helps, let me know if you have any further questions.
>> No conflict. The specified tension is for the right side! The left ends
>> at whatever is necessary to center the wheel with your hub spacing.
>> --
>> Andrew Muzi
>> <www.yellowjersey.org/>
>> Open every day since 1 April, 1971
>> ** Posted fromhttp://www.teranews.com**
>

Art Harris

Gig Miller wrote:
> 72KgF as indicated by the Park Tension Meter feels way too loose. I
> question the precision, not accuracy of the Park meter. Anyone else
> ever run into this with this meter? Has anyone ever set up their own
> calibration apparatus and checked the values?
>

What tension does it indicate on the drive side? It's not unusual for
left side spokes to be half the tension of right side spokes.

Art Harris

daveornee

[QUOTE=Gig Miller]72KgF as indicated by the Park Tension Meter feels way too loose. I
question the precision, not accuracy of the Park meter. Anyone else
ever run into this with this meter? Has anyone ever set up their own
calibration apparatus and checked the values?

Greg


<SNIP>
The charts provided require you to identify the spoke guage involved and look in that column to take the numeric value from the TM-1 and equate it to the spoke tension. There is some friction in the system that impacts the accuracy of the results. I take a couple squeeze & release cycles to make sure the readings come out the same.
I use 220 pounds of weight hanging from a fixture I put together to measure and "calibrate" the TM-1. The chart supplied with my TM-1 says 21 = 99 kgf.
I look to see if 21 is the reading on the Sapim Race 14/15 DB spokes I use. So far the TM-1 has been at 21 each time I have checked it.
I developed the fixture to test my Wheelsmith guage and it seems to have held it's calibration for over 10 years.
I think Jobst helped develope the FSA tension guage. It is more expensive, but it also has very little friction in the measuring system.

jim beam

daveornee wrote:
> Gig Miller Wrote:
>> 72KgF as indicated by the Park Tension Meter feels way too loose. I
>> question the precision, not accuracy of the Park meter. Anyone else
>> ever run into this with this meter? Has anyone ever set up their own
>> calibration apparatus and checked the values?
>>
>> Greg
>>
>>
>> <SNIP>
>> The charts provided require you to identify the spoke guage involved
>> and look in that column to take the numeric value from the TM-1 and
>> equate it to the spoke tension. There is some friction in the system
>> that impacts the accuracy of the results. I take a couple squeeze &
>> release cycles to make sure the readings come out the same.
>> I use 220 pounds of weight hanging from a fixture I put together to
>> measure and "calibrate" the TM-1. The chart supplied with my TM-1 says
>> 21 = 99 kgf.
>> I look to see if 21 is the reading on the Sapim Race 14/15 DB spokes I
>> use. So far the TM-1 has been at 21 each time I have checked it.
>> I developed the fixture to test my Wheelsmith guage and it seems to
>> have held it's calibration for over 10 years.
>> I think Jobst helped develope the FSA tension guage. It is more
>> expensive, but it also has very little friction in the measuring system.
>
>

the friction, while not ideal, doesn't matter that much if it's
consistent and accounted for in calibration. consistency is the vital
thing.

Ron Ruff

On May 13, 4:32*am, Gig Miller <thunderha...@yahoo.com> wrote:
> 72KgF as indicated by the Park Tension Meter feels way too loose. I
> question the precision, not accuracy of the Park meter. Anyone else
> ever run into this with this meter? Has anyone ever set up their own
> calibration apparatus and checked the values?

The Park meter is sensitive to friction, and if this varies you will
get inaccurate readings. I had one with a pivot that would keep coming
loose. After locktiting it and lubing it, the readings changed a lot.
Apparently each unit is crudely calibrated in an unlubricated state,
and the friction (at least on mine) was enough to make a considerable
difference.

I'd recommend checking with another meter to see if they are close. If
they aren't, Park will happily recalibrate it for a small fee.

Tosspot

jim beam wrote:
> Gig Miller wrote:
>> 72KgF as indicated by the Park Tension Meter feels way too loose. I
>> question the precision, not accuracy of the Park meter. Anyone else
>> ever run into this with this meter? Has anyone ever set up their own
>> calibration apparatus and checked the values?
>
> "feels way too loose"? if your judgment is better than the tensiometer,
> why are you bothering with it at all?

I got on a new set of bathroom scales at the weekend. The put me at
55kg, given I'm 6" tall, a fat bastard, with no muscle tone, my "gut
feeling" is they might be a bit out.

However, for you weight weenies, I can offer these scales at a reduced
price of 100 USD, delivery excluded, I can guarantee they'll take 20kgs
of your weight, 30 at a push. The cheapest, quickest, weight loss
you'll ever experience.

dabac

+1

If I do some crude 2-out-of-3 voting on the readings I'm sure there are other factors that will be far more influential to the final quality and characteristics of the wheel than measurement errors.

Tim McNamara

In article
<3c93f945-83ea-4aa0-a1eb-f7f94d1c982e@d1g2000hsg.googlegroups.com>,
Gig Miller <thunderhawkk@yahoo.com> wrote:

> This is my first wheel build. Using 700C Velocity Deep V rims and
> Wheelsmith DB14 spokes.
>
> I have been told by the folks at Velocity that they build their rear
> wheels with spoke tension of 110-120KgF.
>
> Something doesn't seem right. If I take the left side spokes to
> 110KgF, I have to tighten the right side spokes to appox. 180KgF in
> order to get the dish right.
>
> Does this sound right? Is 180KgF too much? If I take the right side
> spokes to 120, the left side seems loose at about 72 KgF.
>
> I'm using a Park Tool Tension Meter to get these values. Am I missing
> something?

Welcome to the dilemma of dished wheels. In order to make room for the
cogs, the right side flange is offset towards the center plane of the
wheel. That results in the left side spokes being much more slack.

The measurement they sent you is for the drive (right) side. The
non-drive (left) side is left to its own devices. If you've got 120 KgF
on the right and 72 KgF on the left, that's as good as it gets with 130
mm spacing and an 8/9/10 speed cassette. I've seen 9 and 10 speed
wheels where the differential is 120/40.

7 speed wheels should have been 130 mm spacing and 8/9/10 should have
been 135 at a minimum. 140 would be better. But because we have to have
fat aluminum/CF/unobtanium chain stays that are stupidly short, that's
not feasible. My 7 speed bike with 135 mm spacing is nearly zero dish
and has been a trouble free wheel since 1996, with virtually even spoke
tension just like a front wheel.