Hi Craig and
to the forum.
Check out
this post for some useful information on calculating spoke lengths.
You will need to enter the correct details for the ERD and the left and right offset of the spoke holes in relation to the centreline of the rim.
With a wide rim, your left and right spokes are likely to be wider apart at the rim than they are at the hub, so you will want to have the elbows on the inner side of the flanges to increase the lateral strength as shown above.
With a standard rim, they are typically closer together at the rim than they are at the hub:
In this case, the wheel will have more lateral strength if the elbows are on the outer side of the flanges as shown above.
Hopefully this is all you will need to determine the correct length spokes for your build.
Alan
