Velocity AeroheadOC spoke length calculation?

[[email protected]]

This question is for Peter V or anyone else with experience building
rear wheels with OC rims.

Does a correction or adjustment need to be made in left/right spoke
length(s) to account for the offset? I'm planning my first build with
an OC. And I'm using a King Classic hub. According to the DT spoke
calculator, a rim with a 598 ERD (such as the AeroheadOC), a 3x
pattern, and 12mm nipples would call for 292mm left side and 289mm
right side length spokes. Should I use those lenghts or do I need to
make an adjustment?

And I assume the tension should be 100-110Kgf right side, and 80-90Kgf
left side. Any experienced opinions?

 

[jim beam]

[email protected] wrote:
> This question is for Peter V or anyone else with experience building
> rear wheels with OC rims.
>
> Does a correction or adjustment need to be made in left/right spoke
> length(s) to account for the offset? I'm planning my first build with
> an OC. And I'm using a King Classic hub. According to the DT spoke
> calculator, a rim with a 598 ERD (such as the AeroheadOC), a 3x
> pattern, and 12mm nipples would call for 292mm left side and 289mm
> right side length spokes. Should I use those lenghts or do I need to
> make an adjustment?

assuming 3mm rim offset, i make spoke lengths 291 & 289, so no
significant difference from what you calculated.

>
> And I assume the tension should be 100-110Kgf right side, and 80-90Kgf
> left side. Any experienced opinions?
>

i make tension ratio left to right to be about 68%, so you're looking
70Kgf max on a 100Kgf right side. /don't/ bother measuring left side
spoke tension for anything other than consistency. you can't increase
left side tension without affecting the dish - tension is a function of
geometry.

fwiw, the king hub is about the worst out there in terms of offset.
maximize the right side flange to center measurement to minimise dish
tension differential. shimano is about the best in this respect.

 

[Sven Longren]

Any correction is in the functional center-to-flange that you'll enter.
Even though that's not where the change is occuring, that's the only
variable that you can alter in any spoke length calculator I've seen. Add
2mm to the drive side c-t-f and subtract 2mm from the non-drive and run the
calcuations.

You may find that things don't change significantly enough to matter. If
you already have spokes that are 2mm different, you will probably be fine.
But change the c-t-f as I recommend and see what you get. My experience has
been that if the calculated difference is less than 2mm, you can use the
same length drive and non. I use the longer spoke and end up with just a
little spoke protruding beyond the nipple.

Off center should be to the non-drive side of the wheel. . .

Make the drive side spoke tension 100kg. The non-drive tension will be
whatever it needs to be to insure correct wheel dish. Just be sure the
non-drive spokes are as uniform in tension as you can muster. That helps
and can be adjusted if necessary.





<[email protected]> wrote in message
news:[email protected]...
> This question is for Peter V or anyone else with experience building
> rear wheels with OC rims.
>
> Does a correction or adjustment need to be made in left/right spoke
> length(s) to account for the offset? I'm planning my first build with
> an OC. And I'm using a King Classic hub. According to the DT spoke
> calculator, a rim with a 598 ERD (such as the AeroheadOC), a 3x
> pattern, and 12mm nipples would call for 292mm left side and 289mm
> right side length spokes. Should I use those lenghts or do I need to
> make an adjustment?
>
> And I assume the tension should be 100-110Kgf right side, and 80-90Kgf
> left side. Any experienced opinions?
>

 

[dianne_1234]

On Sat, 11 Dec 2004 18:13:57 -0800, "Sven Longren"
<[email protected]> wrote:

>Any correction is in the functional center-to-flange that you'll enter.
>Even though that's not where the change is occuring, that's the only
>variable that you can alter in any spoke length calculator I've seen. Add
>2mm to the drive side c-t-f and subtract 2mm from the non-drive and run the
>calcuations.

Sven is exactly correct.

The current version of spocalc has that feature included
automatically. Cell C25 is for rim offset, and it modifies cells C26
and C27 (flange spacing) to give new values in cells D32 and C33 for
use in calculating spoke lengths.