Cheers for the input.
-Triplet lacing greatly restricts rim choices. You need a pretty stiff center drilled rim, or a rim specifically designed for triplet. Triplet has other disadvantages as well.
Please list rims where the manufacturer has stated that they are not OK for triplet lacing; I have never experienced a problem with this kind of lacing, on any rim. If anything, the fact that the tensions are more balanced for each spoke means the rim is happier being laced like this, than a 'conventional' system with a larger discrepancy between the DS and NDS spokes. If this is an issue, though, it would be good to look through it and assess.
-Straight pull NDS puts spokes in the way of where you want the bearings to be.
We have not even started thinking about bearing positions yet, so this point is invalid at the moment. There is the possibility to design a hub with straight pull radial spokes which sit near, or over the bearings, I agree, but we are nowhere near that part of the design stage yet, and it may not even be an issue.
-J Bend is best on the DS for optimizing the offset. This is very important, BTW.
Can you explain what you mean by this in detail please; again, we have not started designing the hub yet, so offsets etc., can not be commented on with absolutes.
-17mm bearings are ok for the rear, but it might be better to reduce the axle diameter on the NDS side of the hub.
'OK'? OK in terms of what? In comparison to what, and why, against what criteria? Also, what good will reducing the NDS axle diametre do?
-Axle and end caps are one unit, with a collar on the outside of the NDS to set clearance.
Again, can you explain (or sketch and photo) what you mean by this?
-Shoulders? You mean steel serrations?
No, I mean shoulders; raised sections in the middle of the axle for the DS and NDS hub shell bearing inner race to sit against, meaning that any lateral load on the inner race will not be able to push the inner race inwards.
I'd advise using higher capacity bearings in the hub body with an axle that captures these bearings, so that the thin freehub bearings won't be subjected to sideloads. I'd probably make the DS hub bearing a 6903 and taper the axle down to 15mm and put a 6902 on the NDS, as close to the dropout as possible. 6803s in the freehub.
I think the first part of this is kind of related to my idea of shoulders on the axle; can you explain more of what you mean by this, as I think we are getting at the same thing! Again though, why do you want to taper down from 17mm to 15mm? Why not just go with a 6803 on the NDS?
About the freebody bearings; I wonder, has anybody got access to, or has indeed carried out, any accurate research about the stresses put through a freebody in a bicycle hub during pedaling? It would be interesting to see what research / engineering theory there is out there, as this will allow us to design a more appropriate bearing system; would the use of angular contact bearings be suitable and better for any part of this, for example?