iirc hooked rims only exist because of inconsistent tire manufacturing decades ago. So basically hookless are not good if you want to run Rene Herse tires but otherwise they work fine? I believe that hookless allows for the construction of a stronger carbon rim. Anecdotally, I’ve been running ragged 48mm reens on some for years without an issue.
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I feel like so much in the bicycle industry it’s retroactive justification for something that saves cost.
I also think that it is transferring the burden for ensuring a safe product from something that is produced in relatively small quantities (rims) that can be subjected to extensive quality control to something that is mass produced in large quantities and can’t feasibly be QC’d to the level of a rim (even a mass produced rim).
It’s also dramatically increasing the risks associated with user error–meaning overinflating the tires, which tons of people will do especially when hookless rims start getting put on mass market bikes.
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I think that it makes sense with tubeless beads, which is where the bike world is now. And I do believe that you can build a rim lighter and stronger by simplifying the shape. It probably does save money too.
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Yup you need bearing ground for clearance if you run them back to back in shaft applications and they only go one way. For single bearing applications or when they’re separated they’re typically flush ground.
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Christ, is this true?!
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^ Dithering thoughts intensify
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But you’re acting like the rim manufacturers are just lining their pockets with the cost savings, when the reality is that hookless makes carbon tubeless wheels affordable for the non-dentists.
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I’ve pinch flatted tubeless twice.
I can feel a difference between 56mm and 25mm carbon rims, the latter having a distinct advantage in comfort. The “comfort” such as it is absorbs larger bumps better.
For example, there’s a section of cobble on my normal route in which tires make the bigger difference, the more supple, the less annoying the cobble. There’s a few spots where roots have kicked up a bump in the asphalt MUP that I generally hit at 18-20MPH. The shallower wheels absorb that a bit better.
Of course, 56mm to 25mm is an extreme difference. I’m guessing that at a certain depth that “comfort” goes away entirely. That is to say, I don’t think there’s a linear difference between the two.
Yep.
Light Switched ON While Cycling @ 10-30km/h
Schmidt SONdelux // 2.50w-6.50w drag
SP Dynamo PV8 // 2.75w-7.00w drag
Schmidt SON28 // 3.00w-6.50w drag
Sanyo H27 // 3.75w-7.25w drag
Shimano DH-3N80 // 3.50w-7.50w drag
This is pulled from a Wired article and actual drag is a moving target. Front wheel is much more important than the rear (I want to say 75% of total drag savings)
“For a normal human riding at 8.33 m/s (again, 18.64 mph, with the same bike and size as the reviewer), I get a power requirement of 148.0 watts. If I decrease the K value to 0.908*0.256 kg/m = 0.232 kg/m, I get a power requirement of 134.1 watts. At this slower speed, you see a power savings of 13.9 watts compared to the high performance savings of 35 watts.”
So yeah… aero wheels in general will at the minimum erase the loss to the dynamo and at best maybe still net you some more speed.
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IME indoor track racing/riding (a nicely controlled environment) it’s enough to actually notice.
Like putting a disc on the back looks cool and sounds cool but not a whole lot of watt savings over a regular wheel with similarly good tires.
Throw a H3, 808 or 1080 on the front (all wheels I’ve used on the track) and it’s like woah, I’m going faster with the same effort.
I’m not an expert… but it’s saving you roughly 10% off you wattage output. That ain’t nothing.
I have heard it kicked around that 15 watts of savings is going to be around .5 mph at normal human speeds and the improvement is non-linear in a good way as you go faster.
Of course, cost/benefit on this is far worse than going from slow or mediocre tires to fast tires. But marginal gains are a thing.
Some GP5ks and aero wheels are going to carry you somewhere between 1-2mph faster at the same effort. Or so the fuzzy math goes.
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Get me into alloy aero rims that aren’t anchors
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Why on earth would you want alloy?
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mig what are you smoking
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Well, this is also going on a bike that’s probably getting 50mm fenders, probably metal ones. I’m having trouble seeing aero wheels having much effect in front of even wider fenders scooping up all those gains.
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Bike has fenders
Do aero rims matter?
RR521?
I know deep wheels make a measurable difference at lower speeds, but when you get in that 40km/h+ range they feel so good and I just wanna go fast.
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Kind of don’t exist. There were the flo ones, do they still make them?
The 521 profile doesn’t look all that aero to me.
I have a set of alloy aero rims from a 3T wheelset. They have a modern U shaped profile, 30mm deep and 26mm wide. They weigh 590g, so they are most definitely boat anchors.
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Are you going to spend much time > 18mph
Why alloy?
only old skool aero rim I would consider buying is the cosmic carbone with the cf fairing. Would love to put them on a ridiculous 1000% doping era road bike.
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