https://cyclingtips.com/...firecrest-wheelsets/
“A wider tire bead interface also allows for a wider tire, which allows for lower tire pressure. Lowering tire pressure can increase overall system efficiency, reduce rider fatigue, and offers better handling in rough conditions.†-Zipp
The new 858 NSWs are priced at $4400 USD / €4000 / £3570 / $6630 AU and 808 Firecrest wheelset will set you back US$2300.00 / £2235.00 / AU$3466 / €2500.00.
So many dumb comments by Zipp.
Let’s start with this one: majority of the 250g saved are from going hookless. Measure the dimensions of the hooks on your wheels and multiply the volume by the density of carbon. Hint, your answer will be somewhere in the 10g range.
28mm will not have lower RR than 25mm unless you’re pumping them to the same pressure. Which you wouldn’t. At the same vertical compliance, RR is essentially the same (within BRR error margins). In any case, if you want to have 23mm inner width to allow for bigger tires, you can still meet 105 rule by making the outside width greater. Just add hooks. They’ll even allow you to run 75psi with those 25mm tires without popping off.
Don’t even get me started on the “smooth interface” being more aero when the tire is wider than the rim. And then unironically followed by dimples right next to the interface.
I will say though, kudos on making a 75mm+ wheel sub-1600g. That’s mighty impressive. Un-kudos for the asinine price. I thought hookless was what made the 303s so much cheaper. What happened to that logic?
So many dumb comments by Zipp.
Let’s start with this one: majority of the 250g saved are from going hookless. Measure the dimensions of the hooks on your wheels and multiply the volume by the density of carbon. Hint, your answer will be somewhere in the 10g range.
I’m confused that you continue to make this claim about carbon volume between hooked and hookless. You are making the assumption that they remove the hooks and that is the difference between the rim styles. The real difference comes in the layup of the rim. Those manufacturers using hookless are consistently yielding much lighter rims because they don’t have to reinforce for the hooks and higher pressures. They’ve also gone all in on disc only which I would wager results in a lot of the weight reduction as most of the older rims didn’t differ a lot between rim and disc brake versions.
I am not sure there is a lot of benefit from TSE and wide tires for race depth wheels. Especially when aero figures into the equation.
The one thing that is clear about hookless is that these rims are less expensive to manufacture so it’s no surprise to see manufacturers go this direction while price points are not dropping (with exception of 303 options I guess)
So many dumb comments by Zipp.
Let’s start with this one: majority of the 250g saved are from going hookless. Measure the dimensions of the hooks on your wheels and multiply the volume by the density of carbon. Hint, your answer will be somewhere in the 10g range.
I’m confused that you continue to make this claim about carbon volume between hooked and hookless. You are making the assumption that they remove the hooks and that is the difference between the rim styles. The real difference comes in the layup of the rim. Those manufacturers using hookless are consistently yielding much lighter rims because they don’t have to reinforce for the hooks and higher pressures. They’ve also gone all in on disc only which I would wager results in a lot of the weight reduction as most of the older rims didn’t differ a lot between rim and disc brake versions.
I am not sure there is a lot of benefit from TSE and wide tires for race depth wheels. Especially when aero figures into the equation.
The one thing that is clear about hookless is that these rims are less expensive to manufacture so it’s no surprise to see manufacturers go this direction while price points are not dropping (with exception of 303 options I guess)
I’m talking out of my rear here but with a disc brake only setup, you can use different potentially lighter layups, carbon and resin as you don’t have the stressors of a braking surface. I do believe I heard (Enve maybe?) that hookless are cheaper and easier to manufacture as well, but I could be miss remembering.
I’m talking out of my rear here but with a disc brake only setup, you can use different potentially lighter layups, carbon and resin as you don’t have the stressors of a braking surface. I do believe I heard (Enve maybe?) that hookless are cheaper and easier to manufacture as well, but I could be miss remembering.
No I think you are correct on the weight save from disc only. But something about the hookless configuration yields further weight reduction. The hooked rim and rim brake combo always seemed to be the big worry for carbon wheel manufacturers in the past.
I think you are remembering correctly for Enve too. I’ve had their hookless AR4.5s for 5 years and they definitely aren’t light weight rims. So something in the manufacturing process has definitely changed with these later rim iterations.
I’m confused that you continue to make this claim about carbon volume between hooked and hookless. You are making the assumption that they remove the hooks and that is the difference between the rim styles. The real difference comes in the layup of the rim. Those manufacturers using hookless are consistently yielding much lighter rims because they don’t have to reinforce for the hooks and higher pressures.
Layup won’t affect density. And if you think there’s a difference in reinforcement, I’d be interested in hearing the logic. If you need less reinforcement because of the lower max allowed pressure, then that’s independent of hook or not. You can make a lighter hooked wheel if you limit it to 73psi max with 25% safety margin. The hooks on a tubeless setup don’t need much reinforcement, especially if the tire that on there is hookless rated anyway. It won’t push on the hook radially, just act as a safety device. The sidewall reinforcement will depend on pressure and nothing else (for disc-only) because the tire pushes perpendicular the walls whether there is a hook or not.
Rims getting lighter over time has been a trend before hookless. Deleting hooks isn’t the reason. Princeton’s 7580 weighs the same (or less depending on hub) than the 858 and has hooks.
Just as a logic check: Princeton’s 7580 and the Enve SES 7.8 rims weigh 530g with hooks. Can you make them lighter without? Probably. But I’m saying it’ll be closer to 10g than “the majority of 250g”. If you want to argue whether its 10g vs an optimistic 50g, that’s fine. But 25%? That’s when it becomes an outrageous claim.
I’m confused that you continue to make this claim about carbon volume between hooked and hookless. You are making the assumption that they remove the hooks and that is the difference between the rim styles. The real difference comes in the layup of the rim. Those manufacturers using hookless are consistently yielding much lighter rims because they don’t have to reinforce for the hooks and higher pressures.
Layup won’t affect density. And if you think there’s a difference in reinforcement, I’d be interested in hearing the logic. If you need less reinforcement because of the lower max allowed pressure, then that’s independent of hook or not. You can make a lighter hooked wheel if you limit it to 73psi max with 25% safety margin. The hooks on a tubeless setup don’t need much reinforcement, especially if the tire that on there is hookless rated anyway. It won’t push on the hook radially, just act as a safety device. The sidewall reinforcement will depend on pressure and nothing else (for disc-only) because the tire pushes perpendicular the walls whether there is a hook or not.
Rims getting lighter over time has been a trend before hookless. Deleting hooks isn’t the reason. Princeton’s 7580 weighs the same (or less depending on hub) than the 858 and has hooks.
Just as a logic check: Princeton’s 7580 and the Enve SES 7.8 rims weigh 530g with hooks. Can you make them lighter without? Probably. But I’m saying it’ll be closer to 10g than “the majority of 250g”. If you want to argue whether its 10g vs an optimistic 50g, that’s fine. But 25%? That’s when it becomes an outrageous claim.
10g or 50g the fact remains these new hookless rims are lighter. So if Zipp’s comment is dumb, then what is your explanation for the weight reduction? And how would you suggest they explain their improvements.
And contrary to your claim. layup will affect many characteristics. This is the point of using carbon in the first place.
It was conceded above that disc wheel only rims are likely the largest difference in overall weight, but you continue to focus on the hook/hookless aspect.
Our article: https://www.slowtwitch.com/Products/Things_that_Roll/Race_Wheels/New_Zipp_808_Firecrest_and_858_NSW_8432.html
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Surely “you†can save a few grams by scrapping the specific heat resistant resin, the little bit of molded hook and reducing carbon to handle the decreased stated max pressures from 120 PSI to ~72.5 PSI (E.T.R.T.O. standard is 5 bar.) However for a variety of strength and impact related reasons I can’t imagine all that much can be scrapped, but that’s just pure uneducated speculation on my behalf. Especially given the heavier disc hubs, I’m impressed by the weight on the new 858, even if I’m not sold on 28mm tires and low pressures for the TT and track racing that I’d be doing with them. I guess I could rip some epic gravel races on them though.
10g or 50g the fact remains these new hookless rims are lighter. So if Zipp’s comment is dumb, then what is your explanation for the weight reduction? And how would you suggest they explain their improvements.
I didn’t say they aren’t lighter. I’m saying they’re taking us for idiots by claiming most of the 250g is from going hookless. We know that’s not possible, and we know Zipp wants to shift fully to hookless so they have a reason to exaggerate any benefit.
My explanation? I didn’t make the wheels, so I can’t tell you if it’s the hub, thinner walls, etc. But most likely most of it is just generic improvements in carbon and hubs that other brands made 5 years ago. Zipp had by far the heaviest wheels until this generation. After all this weight loss, the 808 is on par with SES 7.8
My suggestion would be to just be honest. Obviously not “just better margins for us” but at least don’t oversell claims to the point that they can’t pass a sniff test. “We saved 40g by eliminating hooks, 70g on hubs, and 130g be reducing wall thickness due to lower pressure limits” wouldn’t stand out as odd.
Edit: To clarify, these wheels look excellent on paper. The marketing lines just rubbed me the wrong way. It reads like an adult explaining something to a kid in a nonsensical way, knowing they won’t get it anyway.
Surely “you†can save a few grams by scrapping the specific heat resistant resin, the little bit of molded hook and reducing carbon to handle the decreased stated max pressures from 120 PSI to ~72.5 PSI (E.T.R.T.O. standard is 5 bar.) However for a variety of strength and impact related reasons I can’t imagine all that much can be scrapped
I think we agree then
So many dumb comments by Zipp.
Let’s start with this one: majority of the 250g saved are from going hookless. Measure the dimensions of the hooks on your wheels and multiply the volume by the density of carbon. Hint, your answer will be somewhere in the 10g range.
source?
28mm will not have lower RR than 25mm unless you’re pumping them to the same pressure.
says who?
Which you wouldn’t. At the same vertical compliance, RR is essentially the same (within BRR error margins). In any case, if you want to have 23mm inner width to allow for bigger tires, you can still meet 105 rule by making the outside width greater. Just add hooks.
faulty reasoning.
Don’t even get me started on the “smooth interface” being more aero when the tire is wider than the rim. And then unironically followed by dimples right next to the interface.
why? it’s measurably true and one after another after another premium wheel company are discovering this.
I will say though, kudos on making a 75mm+ wheel sub-1600g. That’s mighty impressive. Un-kudos for the asinine price. I thought hookless was what made the 303s so much cheaper. What happened to that logic?
what as MSRP of the last model year 808 per pair? pre inflation, pre supply chain problems, pre freight robbery?
The chart shows a 4-5 watt improvement (mostly due to aero). But the article mentions only 1 watt?
the article mentions a minimum of 1 watt. i have a follow up article that goes into more detail about watt savings; in which cases; in which wheels. that’ll be published within the next 48hr. that chart you reference in your post is one of several that will be in the follow-up.
https://www.slowtwitch.com/...nd_858_NSW_8432.html
The chart shows a 4-5 watt improvement (mostly due to aero). But the article mentions only 1 watt?
Hmmm…I’m going to need more info on this “rolling road” setup…since the only difference between the bottom 2 lines is tire width (same rim), and the setup really is only going to measure Crr differences (if “like a treadmill”, then the only aero component measured is going to be rotational drag, which should be practically identical)…because I don’t get how at the lower pressures the 28 and 30 tires have the same rolling resistance, and then 28 actually gets 1W faster above ~68 psi?
That’s opposite of the previously measured “wider measured tire widths are faster at equivalent pressure” observations, which is exactly what the 25 line vs the other shows (since this is a “delta” plot).
I wonder what the accuracy and precision is of that test setup? Are the 2 tire width constructions actually “equivalent” (i.e. same casings and tread compound and thickness)?
And how is that “Hooked vs. Hookless”? It’s 2 completely different inner rim widths and different label tire sizes. I suspect both of those things have a much bigger influence than hooks or not :-/
So many questions…
the article mentions a minimum of 1 watt. i have a follow up article that goes into more detail about watt savings; in which cases; in which wheels. that’ll be published within the next 48hr. that chart you reference in your post is one of several that will be in the follow-up.
the 1 watt is the aero savings. so they’re indicating they have made 3-4w savings across the other areas which the little graph shows are all very small proportions of the total resistance - very impressive if true!
the article mentions a minimum of 1 watt. i have a follow up article that goes into more detail about watt savings; in which cases; in which wheels. that’ll be published within the next 48hr. that chart you reference in your post is one of several that will be in the follow-up.
the 1 watt is the aero savings. so they’re indicating they have made 3-4w savings across the other areas which the little graph shows are all very small proportions of the total resistance - very impressive if true!
mind numbing amounts of testing on the Rolling Road trials, one particular guy, a particularly talented Crr crash test dummy, something between high dozens and low hundreds of runs. 25mm, 28mm, 30mm, each at various pressures. this is just Crr that’s getting tested. so, the field testing, that’s the combo of rolling resistance, wind resistance, and whatever biomechanical benefit/cost you get through an increase/decrease of power saved/lost in comfort and muscle vibration. but the rolling road testing is just about rolling resistance. the piece measured isn’t that directly, it’s the amount of power produced to remain at speed. at least, this is what i understand zipp to have done.
So many dumb comments by Zipp.
Let’s start with this one: majority of the 250g saved are from going hookless. Measure the dimensions of the hooks on your wheels and multiply the volume by the density of carbon. Hint, your answer will be somewhere in the 10g range.
source?
28mm will not have lower RR than 25mm unless you’re pumping them to the same pressure.
says who?
Which you wouldn’t. At the same vertical compliance, RR is essentially the same (within BRR error margins). In any case, if you want to have 23mm inner width to allow for bigger tires, you can still meet 105 rule by making the outside width greater. Just add hooks.
faulty reasoning.
Don’t even get me started on the “smooth interface” being more aero when the tire is wider than the rim. And then unironically followed by dimples right next to the interface.
why? it’s measurably true and one after another after another premium wheel company are discovering this.
I will say though, kudos on making a 75mm+ wheel sub-1600g. That’s mighty impressive. Un-kudos for the asinine price. I thought hookless was what made the 303s so much cheaper. What happened to that logic?
what as MSRP of the last model year 808 per pair? pre inflation, pre supply chain problems, pre freight robbery?
I don’t know if your single word answers are just meant to engage or shut down, so I’ll give benefit of doubt and go with the former.
Source for the 10g? On my knight and SES wheels it came out to ~10g. Depending on the hook dimensions of yours, it’ll vary but be in that ballpark. Show me the old and new cross section of the Zipp wheels. Then show me how (most of) 250g savings came from the hook. Thats akin to the weight of the entire rim beds.
RE rolling resistance vs size and comfort level. Wider and lower pressure is faster in many real-use cases because of poor road surfaces not allowing low enough pressure with the narrower tires. But for any given surface, the narrowest possible that can still roll smoothly will be fastest (else we’d just jump to 40mm). Here is what I’ve seen claiming the same comfort level gives the same RR. They’re not perfect, but it’s more than Zipp provides.
BRR: https://www.bicyclerollingresistance.com/...prix-5000-comparison
Continental’s engineer: https://road.cc/...e-right-tyres-279289
Why is it faulty reasoning that you can have both wider tires and still meet the 105 rule busy just making the whole thing wider? How can that even be faulty? Lol. Zipp said having the tire stretching wider is better than meeting 105, but you can have… both.
Which companies have shown that the smooth interface is faster? Never seen a single data point that attributes a wheel’s speed to that feature. Perhaps mavic with the CXR80 had something but those wheels can’t be compared with/without strips since there’s a big recess that sticks out where the strip sits. Roval and Hunt have gone the opposite way and exaggerated the step created by the hooks (one is hollow and the other is filled). They claim it’s faster because it is easier to meet the 105 rule with bigger tires. The air can flow smoothly even if the surface has small gaps, as long as the two disjoint sections line up. So are Roval/Hunt the ones making wrong claims or is it Zipp? In any case, the smooth transition won’t help you with smooth airflow if you have a 28mm tire ballooning to 30mm on a 23mm internal wheel that is 27mm on the outside.
Regarding the price. I said sub-1600g so clearly I’m talking about the 858. The Firecrests are competitive value. The 404FC was in my top 2 when I was purchasing new wheels last year and almost pulled the trigger when i saw them 20% off. Went with the i9.65 which is 7mm deeper, wider, still within 70g, and has hooks. I wonder how they managed that weight with those 150g hooks (just kidding around).
If there are contradicting “sources” and “measurably true” data for the claims you make, I’d be happy to read those if you’re wiling to share them instead of replying in 1-2 words to each paragraph. I like reading about the tech side of these things but haven’t found anything that actually shows that smooth interface is measurably more aero beyond the eye tunnel, hooks save many times more weight than the material they remove, etc. Only generic claims from the sales and marketing departments.
Well said. I feel like the cycling industry is run by marketing departments these days. For example they removed showing drag plots. They also stopped showing white papers/explanations on stuff that really needs explanations such as how they came up with rolling resistance numbers and why having tires much wider than the rim is now ok.
What I’d be curious is what some of the popular tires inflate to as actual width when mounted on those large inner width wheels…
(for example all the new cervelo tri bikes have 36mm clearance I believe, and insist on 4mm spacing on each sides, so anything that inflates to more than 28mm would be a no-go. And then the TSE discussion becomes irrelevant if it doesn’t fit. I’m sure plenty of other bikes are in that regime?)