WMW wrote:I very much doubt it improves anything when you acheive this angle by attaching the spoke off the center of the rim. I haven't tested or modeled the effect (detailed FEM), but it doesn't sound like you have either...?
We did test the principle with a wide carbon MTB rim about 1 year ago with the same principle but external nipples and 3mm offset instead of 2. We compared it to the same wheel with 0 offset. We laced the wheels with same spokes, same hub and same tension. Put the rims between 2 workbenches (and used 3 extra rims below it to support the rim) and hanged a 50Kg weight at the hub and measured deflection.
There was a noticeable difference which proved us the concept worked.
After the campaign when i receive first batch of rims i will redo the test with the Al33 wheels.
WMW wrote:2.15mm nipple bed sounds good. I see you have a 9mm brake track which is nice, but not "weight saving". Compared to a Pacenti SL23 (~430g) you are adding weight in places, plus the taller sidewalls should result in ~50g more weight. Where did you acheive the weight savings? If it is in the sidewall thickness I'd expect a lot of dimpling. Aluminum alloys differ greatly in strength, but density and stiffness do not vary much at all. Do you have a cross sectional diagram which gives all the thicknesses?
WMW wrote:They already posted diagrams of their "proprietary rim shape", and given most of the dimensions. There isn't any magic possible with aluminum unfortunately. You can't make them light unless you remove material, and removing material presents compromises. I wanted to know all the thicknesses so I know what they compromised... or how much they are going to miss their weight target.
Weight is 465 grams for the rim wthout ceramic coating and 24holes for external nipples.
20 hole internal nipples weighed in at 474 grams.
When it comes to wall thicknesses, not a single point is the same, All based upon computer simulations how forces are divided over the rim. Development took us quite a while and also a considerable sum of money. So as far as the sizes go, Everything which we published is what we are open to tell. Hope you can understand we won't be posting our design files straight to the internet.
As said before, the alloy has extremely good material properties compared to other alloys. which allowed us to get the weight down to this point. And when it comes to lateral stiffness, It is really plenty stiff as the rim is 26mm wide at its widest point. Stiffer compared to quite a few less deep, less wide rims we got to work with over the years (same weight or lighter).
svendsvin wrote:bellebikes wrote:svendsvin wrote:... possibility of custom paired spoking patterns...
...It would be too expensive for me to test this first so i simply can not supply warranty on this specific setup. I would recommend equally divided spokes always.
Hi Thanks for your detailed answer. A clarifying question: Is that a No, you will not do it because of no warranty, extra tooling and trouble to make custom drillings (which I understand)
or
Yes, custom drillings would be possible but without any kind of warranty/at my own risk?
Send me an email and we can discuss details, If agreed i can contact my factory and see whats possible. (
info@bellebikes.com).