Enduro/AM - The Weight Game

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Enduro/AM - The Weight Game
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Posted: Aug 26, 2019 at 20:24 Quote
Circe wrote:
The real MVP here

Tks Salute

Perfect opportunity to whore out....(for reference purposes only)


Posted: Aug 26, 2019 at 21:10 Quote
Genuine question and I know I must be missing something..

When a wheel hits a bump, the spokes that actually get pulled on are the ones at 135°since the wheel tries to turn into an egg shape. And wheels are only really in tension and the top spokes are really what's taking the pressure.. But for the moto rims to twist, are they relying on some sort of "compression" force from the spoke to serve as a pivot point? I would think that fiber spokes wouldn't offer that.. But I may be completely over thinking that..

Posted: Aug 26, 2019 at 22:30 Quote
seraph wrote:
sosburn wrote:
seraph wrote:


It's funny that Zipp hubs suck, but the old SRAM X0 hubs were sick. 900 hubs are nice too.

its funny you say that, i have a set of X0 hubs laced to wtb rims, theyre so solid. my only complaint is i wish they were quieter

I love how loud they are. I just picked up a set of the boost 32h version. The rear hub was on closeout in QBP for 50% off regular cost. Thinking of lacing them to Praxis C32 rims.

for 36 poe they are definitely loud, and i do love being able to announce my presence to people before passing with loud hubs but i really feel like i need silent hubs around here. when i eventually ruin those wtb rims ill definitely re-lace the XO hubs, as they are the boost 32h ones as well.

Posted: Aug 26, 2019 at 22:32 Quote
ktm87 wrote:
I wanna do a set of moto rims with berd spokes. Building a wheelset with berd spokes this winter but not sure I wanna pony up the money for the Moto rims

they dont seem to be any more costly than a lot of other big name carbon rims

Posted: Aug 26, 2019 at 22:40 Quote
You didn't get the tirewiz!?

Posted: Aug 27, 2019 at 1:24 Quote
swan3609 wrote:
Genuine question and I know I must be missing something..

When a wheel hits a bump, the spokes that actually get pulled on are the ones at 135°since the wheel tries to turn into an egg shape. And wheels are only really in tension and the top spokes are really what's taking the pressure.. But for the moto rims to twist, are they relying on some sort of "compression" force from the spoke to serve as a pivot point? I would think that fiber spokes wouldn't offer that.. But I may be completely over thinking that..


Hoping the outcome of the above question doesn't involve putting you off purchasing those Berd spokes !

Posted: Aug 27, 2019 at 5:04 Quote
swan3609 wrote:
Genuine question and I know I must be missing something..

When a wheel hits a bump, the spokes that actually get pulled on are the ones at 135°since the wheel tries to turn into an egg shape. And wheels are only really in tension and the top spokes are really what's taking the pressure.. But for the moto rims to twist, are they relying on some sort of "compression" force from the spoke to serve as a pivot point? I would think that fiber spokes wouldn't offer that.. But I may be completely over thinking that..

Here's where your thinking when awry: Spokes don't act in compression. At all*. They act in tension, which is why fiber spokes can work just as well as steel.

There's nothing to lock spokes into the rim, so they just "de-stretch" until they go slack, then they buckle or poke through the rim as if you were lacing a wheel and everything was slack. When you build or true a wheel, you probably put the wheel flat on your work bench and push down on the rim to get the wind-up out of the spokes. If so, you've probably felt spokes go slack and either buckle or poke through the rim's spoke bed and touch your fingers. One of the challenges of tubeless, single-wall rims is how to accommodate the "poking through" without damaging or detaching the rim tape.

The twisting of the rim - which isn't unique to the Zipp rims, though I'm sure they can do it a lot more - is simply because the rim has very little torsional stiffness. That's not to say the wheel has little lateral stiffness, though, because that's mostly a combination of spoke stiffness and the lateral - not torsional - stiffness of the rim.


* Except Mavic Tracomp spokes and rims, but who uses those? Solid carbon wheels, like Bike Ahead, also work in compression.

Posted: Aug 27, 2019 at 8:33 Quote
If you are closer to 200 lbs than 160 lbs and really like to drive the corners I would give the Moto rim's a pass. Talking with someone that has tested them he said they felt like he was riding a low pressure flimsy sidewall tire.

Posted: Aug 27, 2019 at 8:44 Quote
R-M-R wrote:
swan3609 wrote:
Genuine question and I know I must be missing something..

When a wheel hits a bump, the spokes that actually get pulled on are the ones at 135°since the wheel tries to turn into an egg shape. And wheels are only really in tension and the top spokes are really what's taking the pressure.. But for the moto rims to twist, are they relying on some sort of "compression" force from the spoke to serve as a pivot point? I would think that fiber spokes wouldn't offer that.. But I may be completely over thinking that..

Here's where your thinking when awry: Spokes don't act in compression. At all*. They act in tension, which is why fiber spokes can work just as well as steel.

There's nothing to lock spokes into the rim, so they just "de-stretch" until they go slack, then they buckle or poke through the rim as if you were lacing a wheel and everything was slack. When you build or true a wheel, you probably put the wheel flat on your work bench and push down on the rim to get the wind-up out of the spokes. If so, you've probably felt spokes go slack and either buckle or poke through the rim's spoke bed and touch your fingers. One of the challenges of tubeless, single-wall rims is how to accommodate the "poking through" without damaging or detaching the rim tape.

The twisting of the rim - which isn't unique to the Zipp rims, though I'm sure they can do it a lot more - is simply because the rim has very little torsional stiffness. That's not to say the wheel has little lateral stiffness, though, because that's mostly a combination of spoke stiffness and the lateral - not torsional - stiffness of the rim.


* Except Mavic Tracomp spokes and rims, but who uses those? Solid carbon wheels, like Bike Ahead, also work in compression.

Totally didn't thinking about the fact that there is nothing from stopping the spoke from pushing through the rim.. Duh on my part.. So the spokes are holding the rim true, but the moto rims just have lots of torsional flex compared to other double wall rims..

Posted: Aug 27, 2019 at 8:58 Quote
swan3609 wrote:
So the spokes are holding the rim true, but the moto rims just have lots of torsional flex compared to other double wall rims..

Exactly.

Posted: Aug 27, 2019 at 10:56 Quote
R-M-R wrote:
swan3609 wrote:
So the spokes are holding the rim true, but the moto rims just have lots of torsional flex compared to other double wall rims..

Exactly.

Sweet.. I wish I understood more about wheels and the physics behind them.. I build a dozen or so custom wheels a year. We have a wheel builder in house, but I get a hand full of custom wheel builds myself in.. Our Phil wood machine is rad and allows us to build custom wheels on the spot lots of times for customers.

Posted: Aug 27, 2019 at 11:09 Quote
fredro wrote:
Circe wrote:
The real MVP here

Tks Salute

Perfect opportunity to whore out....(for reference purposes only)


needs some EE-Wings

Posted: Aug 27, 2019 at 11:27 Quote
EE-Wings cranks are nice but personally I think the titanium color ruins a lot of builds. They look more at home on a titanium hardtail.

Posted: Aug 27, 2019 at 12:18 Quote
seraph wrote:
EE-Wings cranks are nice but personally I think the titanium color ruins a lot of builds. They look more at home on a titanium hardtail.

couple of guys here are running them on enduro/park rigs and love them. these guys have bent most other cranks.


 
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