DaveSSS 

​​​​​​Hookless rims are not significantly lighter and any road bike tubeless tire that isn't already hookless compatible soon will be or they won't sell many. Nearly all big name brands are already hookless compatible. Tubeless is not really being touted as lighter, but it can certainly reduce punctures. That's why I use them. I got a double puncture from a 2 inch construction staple. I head to stop and pull it out, but the punctures sealed. I added some CO2 and finished the ride with no problem. The puncture remained sealed for another 2000 miles, until it was worn out.

Race bikes are no longer all run on skinny tires. 28mm is already already being used and a 200 pound rider only needs about 65 psi.

tomato coupe

That still doesn’t answer the question, which is “why hookless?” 4 psi less on a pressure chart doesn’t answer the question, because there’s no reason you can’t run hooked at that same pressure.

garysol1 

Lets not forget that the Zipp warranty is LIFETIME and includes damage due to potholes, rocks and what have you so yes, that matters to me.

Spandex_fairy

Is there any difference in handling when going from hooked to hook-less tires of the same size, pressure and inner width? One thing not mentioned often is feedback. I feel much more confident bombing into a corner on wide, low psi, tubeless performance wheels/ tires. I feel more connected with the road. I know hook-less provide an aero advantage, but I wonder if they're equally confidence inspiring while cutting a corner.

msu2001la

I don't think there's really any difference in on-bike performance between hooked and hookless. The differences are in rim construction, cost of construction and a tiny bit of weight. Zipp claims some aero advantages to hookless, but this seems marginal at best.

In terms of confidence in the system - I've ripped through many hard corners during CX racing on hookless rims with 33mm tires at 25psi. I've never had one come off. My confidence on this setup is the same or greater than it is on a glued tubular.

msu2001la

You are confusing a lot of talking points here. Hooked and hookless can both be tubeless, and both use the same valves, sealant and "heavy ass tubeless tires". It seems like your complaints here are about tubeless in general, and have nothing to do with the hook design.

If you like skinny tires at high pressure - go for it. I don't think anyone is going to try to convince you that tubeless makes sense for this. This isn't typical for the road riders I know - most have moved up to 25-28mm tires and some go even wider, and we all run much lower pressure than we were 20 years ago.

On the topic of the hooks being more secure, maybe - but I don't hear many stories of hookless tires suddenly coming off the rim, and it's definitely not something I've experienced after using hookless rims for the last 18 months or so. This mostly seems like a made up problem that doesn't really exist.

In terms of availability, most if not all of the top tubeless road tires are hookless compatible now. Cost? Sure, tubeless tires are a little more expensive than tubed tires, but this is a thread about $1300 aftermarket carbon wheels that will be plugged into bikes costing 3-4x as much. Can you really argue this point with a straight face? If you're fretting over $40 a year in extra cost on your fancy road bike with carbon race wheels, you've seriously messed up somewhere.

Agree, 1500g for $1300 is not going to get the weight weenies very excited. The warranty is nice though.

I've never heard of BTLOS, but I considered buying wheels from Light Bicycle and was pricing out something in the $800-$900 range at around 1450g, and decided to buy the Zipp 303S instead.

I don't think anyone claims that the Zipp 303S is the lightest or best weight/$$$ purchase out there. 1500g is pretty average for a 45mm deep carbon wheelset and Zipp's higher end 303 Firecrest is a more brag-worthy 1300g. I'm also not sure there's any real performance difference between Zipp and any of the generic Chinese carbon wheels out there - but Zipp develops their own products, and they're a trusted name US brand that offers a lifetime warranty. That's a factor for many, and for me it definitely pushed the decision into buying Zipps.

DaveSSS 

If you want a deep profile wheels and light weight, be prepared to pay $3-4,000 for a set. Most people don't compete, so there's not much point in paying maybe 4 times as much to save a little weight, but it's your money. BTLOS offers a large number of rim configurations that they sell separately or as built wheels. I've got 303s wheels and one set of BTLOS, with another set on order. I get mine with no spoke access holes, so no rim tape required. Just add a note to your order. Two sets cost about $1600. I've never had a warranty claim on any cycling component in 35 years, so it's not much of a consideration for me. BTLOS has excellent service by e-mail. Just keep in mind the time difference.

Below is Enve's take on hookless.

https://www.enve.com/journal/behind-...20construction

Sy Reene

In my case, if I were to run road tubeless, I'd want 28mm tires and also be inflated to approx 80 psi. Hence, no interest in hookless. It's a simple decision for me. ymmv

phrantic09

I picked mine up last year for under 1k when ProBikeKit was having a sale

garysol1 

Why would you want to run 80psi in a 28mm tire running tubeless? Serious question.

DaveSSS 

Finding a hookless rim brake rim might be difficult. Hookless goes hand in hand with disc brakes. A 23mm IW rim would support a 230 pound rider with 70 psi. https://axs.sram.com/guides/tire/pressure

*** Assuming a Merlin Cyrene rim brake bike.

tomato coupe

??? He made no mention of rim brakes.

Sy Reene

tomato coupe

Your tire pressure bible is not the true tire pressure bible.

(I run 60 psi for 32 mm road tubeless, so 80 psi would also be roughly what I would want for 28 mm.)

Sy Reene

Lots of bibles out there.. Here's Pirelli's PZero TLR chart. I'd still be too close to being an edge case that I wouldn't be sold on doing hookless, given that I don't see the downside of hooks.

tomato coupe

Blasphemy!

msu2001la

Since the topic of this thread is the Zipp 303S wheelset, it seems like it would make sense to use Zipp's tire pressure calculator.

For a 205lb rider on an 18lb road bike running 28mm standard tubeless tires on the 303S (21mm i.d. hookless rim), that calculator shows 64.6 PSI front/ 68.76 PSI rear. They suggest 58-61psi for wet conditions.

garysol1 

Zipp 303s is a 23mm internal not a 21mm. Using standard sidewall TR tires the Zipp calculator shows 62.2psi front and 66.2 rear. Not a big difference but worth noting I guess.

msu2001la

Even better.

tomato coupe

Does that mean we should use a different tire pressure calculator for any non-Zipp wheels?

msu2001la

I'd generally go with whatever the wheel manufacturer recommends, but you do you. Enve's calculator gives similar results as Zipp's.

I'm not sure why anyone would ignore Zipp's calculator in a thread about Zipp wheels, but yup - that Perelli chart and the unknown chart above do show high numbers.

Sy Reene

Maybe they know what their tires can manage. The unknown chart is Silca's 'pro' calculator.

Zipp's calculator is just developed to progress and end at 73psi for the max weight they want to market their wheel as being able to handle (250lb rider, in order to compete with lot of other wheelmakers who want to say their wheels can handle 250lbs). The 303S I think is optimized for a 28mm tire, so with that width, the calculator results in 73psi for a 250lb rider.

Sy Reene

fwiw, the 205 entry in Silca's calculator was an entry for total system weight -- bike+rider+misc (water bottles). A total system weight of 222lbs (205+18) would have returned even more disparate results.

tomato coupe

I think the salient issue is that numbers provided by tire pressure calculators should only be considered approximate starting points. There is no universal agreement about the "correct" tire pressure for a given set of conditions, and the range of results from different calculators illustrates that.

msu2001la

The Zipp calculator will say "not recommended" if you exceed the limits of a hookless option, and will return values above 73psi for hooked options.