New Shimano parts group

[rideit]

DW isn't doing 'bents, so Spats don't care.

[pechelman]

ok
so yea, a serious post

Im sorta with spats here and sorta on the other side.
The jump to 15mm really is pretty stupid and pointless.
Sure it will be marginally stiffer, but as he mentions, thats not where the most gain is to be had. Unfortunately, compromises must be made and reality prevails with changing flange width and therefore hub width.

Im not sure anyone would disagree a wider hub would be better, but what would it take to make that happen? As it is companies are all into their own proprietary shit.

Also, I might question your numbers spats. Where did you get them?
Im also under the impression people currently use and ride on rims that weight ~400gms.
I mean at least I know I do on my old hardtail and current FS bike.

Further, and granted we're just talking a few degrees here, but increasing flange width will place more side loads on the spoke ends, nipples, and wheels. Those will need to be made bigger or stronger in those areas to accommodate this. Im just not saying its so black and white and without compromise to go wider. (cause I do agree with you)

Also, ive never built a wheel or looked into it, but wouldnt a wider flange spacing and therefore higher spoke angle require a higher spoke tension to maintain the same vertical stiffness? (or is it the other way around)

and like you mentioned with C-Dale, its really surprising they didnt go with a wider spacing on their lefty. Their was no constraint to keep them from doing so. Of course I just think thats a stupid Idea to begin with anyway, so whatever

[rideit]

This has no relevance to the conversation, but I have built ~1000 wheels in 25 years.

That is all.

[chaka]

for the weight weenie xc crowd, i bet you could design a lighter 20mm version of things, and still retain the major stiffness from a 20mm axle without having to resort to a new standard.

This gets at my issue... I suppose I fall into the 'weight weenie xc' crowd in that I consider weight as a factor (not obsess over it but def consider it) when buying components, ride predominantly xc, and enjoy xc /endurance racing. I'm fairly light at 155lbs, and would guess a lot of other WWXC types who are either recreationally or seriously interested in racing are fairly light as well. I have never noticed flex from a standard QR hub axle, the flex I have noticed in wheels most often came from poorly tensionsed wheels, thin spokes, less than high end rims, or some combo of the these. Or, in the front, I've found a small stanchion diameter fork can introduce a lot more flex than the wheel.

I haven't ridden a 20mm thru axle wheel. Would I be blown away by a 20mm/15mm wheel, or are the standard QR axles plenty stiff for me at my weight and riding preference. I guess I've never bought the argument that people like me need a stiffer axle. What are you guys riding (and eating) who fall into the "ride XC but standard QR is too flexy" category.

[Spats]

pechelman: The numbers are just basic trig on bracing angle. There are plenty of other things involved -- obviously rim stiffness matters, and spokes don't have zero lateral stiffness, but it's easy to calculate the stiffness gained/lost from spoke triangulation. I actually took some real-world lateral deflection numbers from one of Damon Rinard's pages and put it up against the simple model, and though the data is very noisy, it is in the correct range. Which doesn't conclusively prove anything, but it suggests that the simple approximation isn't too far off.

As far as vertical stiffness/compliance, it's hardly affected at all by increased bracing angle, because cos(small) is barely changing vs. sin(small). And AFAIK, increasing flange with causes the spokes and hub flanges to take more tension and *less* lateral/bending load. Think about it: if the wheel gets a side load outside the bracing angle of the spokes, the spoke's bending resistance is the only thing keeping the wheel together, and you usually get this:



For the record, I think DW is awesome, because he's one of the few real engineers working in the industry -- and after many years, he's finally starting to get a little clout, which is good for him.

However, Trek is using Split Pivot, not the dw-link, and Split Pivot is just a clever way to get around the Horst Link patent. The rest of those companies are tiny boutique operations that don't matter in the grand scheme of bicycle retail.

[rideit]

Flange width and spoke strength issues can be resolved/addressed with straight-pull spokes, of course.

[bagtagley]

Think about it: if the wheel gets a side load outside the bracing angle of the spokes, the spoke's bending resistance is the only thing keeping the wheel together, and you usually get this:

Usually? Give me a break, Spats.

However, Trek is using Split Pivot, not the dw-link, and Split Pivot is just a clever way to get around the Horst Link patent. The rest of those companies are tiny boutique operations that don't matter in the grand scheme of bicycle retail.

I added Trek in jest because, last I heard, dw is in the middle of a legal battle with them over patent infringement. Split Pivot is dw's system, Trek calls it the Active Braking Pivot. None of that really matters, though. If you still think IH is a "third-tier operation", you haven't been paying attention.

[superstator]

This gets at my issue... I suppose I fall into the 'weight weenie xc' crowd in that I consider weight as a factor (not obsess over it but def consider it) when buying components, ride predominantly xc, and enjoy xc /endurance racing. I'm fairly light at 155lbs, and would guess a lot of other WWXC types who are either recreationally or seriously interested in racing are fairly light as well. I have never noticed flex from a standard QR hub axle, the flex I have noticed in wheels most often came from poorly tensionsed wheels, thin spokes, less than high end rims, or some combo of the these.

Amen. I'm an xc fatty at 200lbs, and I've never noticed flex in the axles. Spokes, rims, forks, but never the qr axle. If I'm that worried about weight, I'll start spending my big mac money on titanium skewers.

My guess is they're more interested in replacing 20mm than QR's. They're just trying to get traction for the idea with us xc nerds and hoping it'll percolate up to the DH and FR crowd...

[rideit]

It's not the Axle that flexes, it is independent movement of the fork legs.

[gravitylover]

If you still think IH is a "third-tier operation", you haven't been paying attention.

If you've ever had the "pleasure" of doing business with them you too would consider them a third rate operation. They may have a few nice bikes in their line but otherwise they suck.

[kidwoo]

I actually took some real-world lateral deflection numbers from one of Damon Rinard's pages and put it up against the simple model, and though the data is very noisy, it is in the correct range.

How noisy?

Like orders of magnitude? I can't follow your reasoning until I know your standard deviation, the results of a weighted mean with regards to material alloys assumed in the model...... and at the very least.......the last time you got laid.

[bagtagley]

If you've ever had the "pleasure" of doing business with them you too would consider them a third rate operation. They may have a few nice bikes in their line but otherwise they suck.

To me, third rate <> third tier. Love 'em or hate 'em, they don't seem to be having any trouble selling bikes.

[gravitylover]

Lets see what happens without DW in their camp anymore...

[bagtagley]

Lets see what happens without DW in their camp anymore...

That's a solid point. I guess we'll see just how dedicated the Sam Hill fanbois really are. Unless Hill follows DW. It'll be a massive bike forum fanboi brand migration.

[BeyondDan]

Lets see what happens without DW in their camp anymore...

It'll empty as fast as the Jim Jones camp post Kool Aid shindig. Maybe I'm biased having owned an IH MKIII, Mojo and Mojo SL (typing with my DW Link tshirt on).