Do you use hookless rims on your bike currently? Do you have any further questions about them?

so good to see Si hosting this GCN tech

i purchased a very expensive set of carbon hookless rims at my local bike shop. They sold me some nice, expensive tires to put on them. After a full weekend of wrestling with it, the tires would not seat or seal. Turns out the tires weren't compatible with the rims. So we checked with the wheel manufacturer.. they basically said, 'we only tested it with ONE specific tire MODEL, and only in one specific size, and only at a very specific pressure at that. So, we tried that tire (not a tire or brand I was fond of mind you), and still had a terrible time getting it over the edge of the rim, even using metal tire levers (after snapping several plastic/nylon levers). These wheels were specifically intended to use on a gravel bike. I live in an area where it is often cold and wet and dark, and almost all of the best gravel riding is in areas with little or no mobile phone coverage. Then we asked if they supported running tubes in these tires.. the answer was a firm NO. Which means no emergency tube/boot install. I sent an email to the manufacturer asking them how I could get possibly service this tire in the field - i.e. on the side of a gravel road or trail, potentially in cold/wet/freezing weather, and outside of mobile phone service area. They had no answer. My comment was a very pointed request for a refund, which they granted. The shop doesn't sell that particular brand of wheel any more - at least they didn't last time I was there. Keep these simple thoughts in mind when considering spending money on hookless rims. What tires are you going to run, and at what size and pressure? Are those tires compatible? (ask the wheel company and the tire company - you'll probably get VERY different answers from both). Are you willing to limit your tire choices to those that are compatible? What happens if you cut a sidewall, or have some problem that requires you boot the tire and put a tube in? Bottom line, what benefit are you getting from hookless rims that make it worth dealing with all of this hassle? I'm back to hooked rims and safe tires that can support a wide variety of sizes and tread options, and have the options of running tubes. I'll be there for a while. For those that opt to go with hookless rims, best of luck to you.

SI is just BRILLIANT - His explanations seamless. Kudos !! Really appreciate him !

We’ve been talking to Zipp and Pirelli to get completely independent and unbiased answers 😉

Definitely one of the most informative videos from GCN Tech. Answered questions I didn't know I had. Thanks!

Always love the deep dive into bike tech nerdery. Thanks, GCN.

Such a good explanation. I'm hooked.

Grrreat video! Tonne of information condensed in to a single place. Very useful for learning and future reference!

Great video and explanation. I always ride tubeless but never heard of this. Think it is good to dive into this and checking my wheels and tires. Thanks 👍🔝

Super geeky, super detailed but oh so satisfying to watch. Thanks.

On a ride today with my friends and one had a flat. He was riding his new Orbea (beautiful bike) . Imagine our consternation when we tried to take the tire off the rim only to find it was stuck, almost like it was manufactured in one piece. The tire was fully deflated but we could not get the tire bead to come free of the rim edge. We, 4 men, worked on this for 30 minutes before resorting to youtube and finally a call out to bike mechanic friend who told us it was a new "hookless rim" and we needed to basically "man up" and force the tire to break seal with the rim edge. Another 30 minutes with the strongest among us finally using a two hand twisting motion on the tire perpendicular to the diameter of the rim and the bead finally moved to the center of the wheel, where we could get a tire lever under it and fairly easily hook it over the wheel. On closer examination a "hookless" rim has two shoulders around the outside edge of the wheel where the bead of the tire when mounted is stretched so tight by the extra height that it makes a almost unbreakable seal. This is an incredibly hard thing to deal with on the road, and that is putting it mildly! So why would anyone create such a difficult to deal with wheel system?? One final detail, while a new bike and wide rims, think they must have measured 25mm width internal, maybe?, due to shortages the bike shop put on 25mm wide tires, was this the reason we had such problems, would a 28 or 30 have been a different experience? My buddy is ready to shop for new rims, any feedback would be appreciated!

Thanks a lot for your brilliant explanation!

Bought a pair of 303 and running Pirelli PZero SL. A breeze to install and pump and the most comfortable setup I had in years. Running 58/62 PSI front and rear. Never go back!!!👍

Wow, clicked on this vid reluctantly but have been pleasantly surprised. Really informative and interesting.

Thank you so much! Great video

Really good video, thanks👏👏👏

Super useful thank you

Thanks 🙏🏼 interesting video thanks for sharing your video GCN.

Interesting video! I didn’t understand half of it, but am now well up for buying a pair of hookless rims! Thanks 😃👍

Brilliant as you say to see the industry working so hard to find common standards that all can agree and use for production. Now, about those bottom brackets....

Great info

Super helpful video to bring me up to speed. Thanks

Excellently presented. Didn't seem to be a sales video for Zipp or Pirelli. Having said that, I'm almost certainly going to try these 303 Firecrests with Pirelli tyres this summer 😂

Still on hooked carbonclinchers with latex-innertubes and rimbrakes.

Perfect timing! I just learned that my GP5000 TL may not work with my hookless rims, which led to researching this subject! Thanks!

thanks GCN

5,000 miles on my new Zipp 303S hookless wheel set. Love tubeless! Love the ride quality! Loved the price!

Using new Zipp 303 Firecrest hookless wheel with 28mm Schwalbe Pro 1 TLE tires at 51/58 tire pressures. Everything so far has worked great. Easy to mount the tire and able to inflate with a track pump. Ride quality is excellent.

Si is so good at this, serious yet not over technical

Thank you for all your videos, I have learned a lot. I'm in the process of switching to tubeless on the advice of my local bike shop. I'm wondering if you have switched yourself?

Great to see Si again, what a champ!

Really helpfully video this GCN Tech thanks. I have a question for you though. What’s the deal with Zipp 303s wheel sets and the Continental GP5000 tyres. I’m hearing they’re not comparable. What’s your thoughts?

I have had this type of wheel for three months now, Zipp 303s. They feel amazing to ride at around 50 psi with 28mm and I have more confidence cornering at speed. Not to say 25mm tubed tyres can't corner well but the feel and my perception of grip make it easier for me to trust the bike. The Vittoria Graphene 2.0 only lasted until two days ago when I noticed the tread layer was coming unglued (LBS will do the warranty thing for me), so I took them off and installed the P Zero Race TLR set I ordered a while ago. I had researched compatibility with hookless (tubeless straight side or TSS) but when I unpacked them there is a warning molded into the tyre "do not mount on hookless rims". I was initially very frustrated with this but went to the internet and apparently the first batches were made before testing was completed at Pirelli. The tyres went on as easily as a conventional setup but I used an airshot to seat them. I think I might have gotten away without it but I had no trouble adding Stan's and inflating them. My feelings about TSS so far are positive, but remember to check your pressures regularly and add sealant if they are deflating quickly. With the Vittoria tyres it was a little over two months here in Brisbane and the sealant needed refreshing. I would say if you are in the market for new wheels then go for it, there will be some things to learn and buy but nothing more difficult than running tubes in my opinion and they feel much nicer to ride. Happy cycling!

I've got hookless ( plain rims ) on a 1951 BSA Sport. 26 x 1 1/4" 32-597. Also a Raleigh 20 shopper 20 x 1 3/8". Also a Moulton Mini, 14 x 1 3/8".

Last week my new 28mm Conti S TR tire blew off my new Zipp 353 NSW. Just sitting in my living room at 73PSI while I got ready for my first ever hookless ride.

Very helpful, and compelling. I do have a question on mounting and repairing a puncture should it occur while riding. I’ve heard it’s a messy process. Can you speak about that? Grazie

I expected this video from doctor Bridgewood, but i missed Si lately, so it's a very welcome figure

Rode a set of hookless rims with tubeless tires at 5 bar for a year or so. Fitted a new pair and rode it at the minimum pressure printed on the tire of 6 bar. The rear blew off after 15 mins of riding... Stick to the 5 bar limit!

Si = great videos.

Correct tolerances are critical to press fit bottom brackets too, but I think we all know how that's worked out. I hope they do a better job with hookless rims, but I'm not convinced they will.

I had no idea about all this hookless stuff! Thanks for the heads up.

Thanks for informative video- 5 bar would seem to be a bit low for the tandem 130kg?

Thanks excellent video. Well what i want to ask you is if its possible to use this wheel without tubeless and a tire pressure of 100 to 120 psi? Whould you take the risk o just make another wheel choice? Thanks!!

I’m sticking with hooks, you can use whichever tire you want.

Cool video Si. I've been riding tubeless for three yrs. I went tubeless because I thought was cool but, little did I know how much I would enjoy all the haters telling me tubeless horror stories, and they reason why they'll never ever go tubeless.

Hi, very good explanation. I only have one doubt. Does the TLR tires work on this rims or it has to be especifically tubless. thanks

Im embracing hookless & have some 303 S rims on order. LBS said I won't get them until January or February though!

I have the new ZIPP 303 firecrest hookless rims and have schwalbe pro tubeless 28 mm tires set up on them. There work flawlessly with about 60 psi for me (80kg). I highly recommend! In fact, it was Si’s video about the new Zipp wheels in the summer that convinced me to go this route. Thanks Si!!

I used tubeless tires for a while, not worth the trouble. They do work, but when you have a puncture that's to big the you are left with the mess of cleaning out the sealant at the side of the road, before you can put a inner tube in.

With my bikepacking tendencies, I’ll stick with hooked... if I need to replace a tyre out on a trip, I don’t have to worry about what tyres are available

You would think that Si, would use SI units like bars for pressure and not imperial measurements.

My head is melting. I just like riding my bike and enjoying the freedom. Tyre and tube is fine for me, don’t need to spend forever stressing on what’s compatible with what, just get on the bike and ride!

Thank you for this videos, I suggested it not long ago. All the best and good content.

@GCN Tech .. is the "Pirelli Cinturato Velo TLR" for hockless rims??

I am mainly interested in the tire pressure advantage/disadvantage thing; could you explain on that, maybe in some dedicated video?

Am running 2019 tcr, clincher and Conti 5k. My rims can run tubeless too, how to confirm if mew conti tires are compatible ? Thx!

I have a new pair of 303 firecrest. I race mostly criteriums, what tires would you recommend ?

#AskGCNTech for your disc brakes you have different disk pads. there are also ones with some kind of cool ribs. like Shimano L04C. is it really necessary to use these when driving in the mountains. and how much are they cooling?

Very interessting that my Schürmann steel rims from the 70s are hookless as well

I have some question, so what tubeless tire is compatible with zipp 303s? If you have to choose campagnolo shamal carbon or zipp 303s what will you choose and why? Thx before🙏

When will we see Zipp 202S be released?

Great to hear that the new standard "leaves no ambiguity". Instead of 622mm, it's now 621.95mm. Plus/minus 0.5mm. 😋 Love this.

Could I use these wheels 303 firecrest with chamber inside? On the page it says that a good size is 700x28 and I have the good year supersport, but when putting them on it is impossible to fit them with a chamber inside, other mechanics tell me that they can only be used with tubulars, thanks for helping me clear up my doubts

You mention that hockless wheels will be cheaper but you buy them just once. What about the high price different of tubeless tyres which you buy more frequently, compared with the price of normal tyres?

Si, you mention that one can still use a tube with these wheels and some tubeless tires. I don't have any experience with tubeless wheels and do get flats from time to time, when I ride (I have clinchers with tubes). So, how easy is it to repair a flat that a sealant is unable to cover, vs. using a tube with tubeless tires? Cheers! Manny

I used a schwalbe mtb marathon wire tire (clincher) with a tube on my hookless cross country rim for over 4000km, never had an issue, infact, kevlar bead tires got so loose after 800km that they wouldnt hold pressure for an entire day

And what are the wheels brands doing about the chance of damage on the rims caused for hitting a pan hole, for exemple, riding tyre pressures as low as under than 5 bar?

I just purchased some Giant SLR1 hookless wheels with Cadex 700x25c tyres - Giant's own website recommends running 84psi for a rider my weight (with recommendations of up to 100psi for heavier riders). I keep hearing the 72.5psi limit (mostly through other GCN videos), but can't find any references to it from Giant or Cadex. It sounds like this limit can be ignored (unless the manufacturer says otherwise) and the ETRTO guideline is somewhat arbitary? Thanks for the video. Feeling less scared about the wheels now (confidence will come once a few thousand km are on them).

But the wheel weight doesn't matter right? You had that video where you spoke to the Swissside guy. Might aswell get the wheels that don't cut your tyre choices in half.

So can I use the Pirelli p-zero TLR on hookless rims?

so if you have a hookless rim that is meant to have a max pressure of 72.5, but a tubeless tyre with a min pressure of 70psi, and a chart that say i should inflate my tyres to 80 psi, what pressure to you use.

I have these ZIPP 303 firecrest hookless rims fitted with GP 5000s TL - I really love them but I find I lose pressure every couple days - going from my preferred 60 psi to a 40ish. Does anyone know if this is normal ?

So if i wear to go hookless rims and get the right tubless tyres but needed/wanted to put a tube in it would that be a problem? And would i still run it at the lower pressure?

In a critical puncture it's possible to fit one inner tube to keep going and back home or stop no next LBS?

How is the use of sealants in these hookless setup? Same as to "older" tubeless?

SAFETY FIRST !! In an industry that values marketing hype and profits over engineering quality assurance/control I am not convinced by this technology yet. Many bike manufacturers still use the consumer as a lab rat by releasing unsafe or not thoroughly tested compatible product.Creaky BB's,holes that are not round,headsets with internal cable routing that can wear and fail,forks that can fail,cranks that fail,the list goes on and on. The whole bike/tyre industry needs to get their shit together IMHO.Standards are not standards until everyone agrees and strictly adheres to them,without conflicting standards and the highest level of QA/QC.

Almost 500 km since using Zipp 353 NSW wheels with Vittoria Corsa Next 28c tires. So far i don't have any problem with this setup. But i did ordered 30c tires, i think 30c will be sweet spot for this wheelset, will be more comfortable, stronger feeling and also i don't think it will be any slower. Roads are mostly not in very good condition where i ride. Also i don't think they are cheaper. I was going to buy Bontrager Aelous RSL 51 but then decided to go with Zipp NSW 353. Lighter and more comfortable for all around use, instead of pure aero. Plus they were almost same price, Bontrager a bit expensive, that's it.

Hi is it ok to use the Zim303s with inner tubes ?

Interesting to see from your video that Pirelli emboss tyre info just above the bead. I have found that the tyre doesn’t quite seal at that position until the sealant works it way around to that position. The raised writing compromises the bead rim interface. Not a huge deal obvs but why put it there? Great clear video 👍

Wow Si twice in one week. Bonus

What width of tyre do Zipp think I'm running if the optimal pressure is "substantially below 72psi"? That sounds like they're talking about, say, 60psi, which sounds extremely low for, say, 25mm tyres.

I’m sold.

Been using tubeless with hooked carbon rims for over 12 months now and really like them. Just not convinced with hookless yet. What happens when a tyre punctures that won't seal and deflates, will the tyre remain seated or possibly roll off the rim? at least with hooks your guaranteed the tyre will remain seated even with a deflated tyre.

Do we still use sealant for tubeless tyres and hookless rims?

I feel like a lot of the safety fears are founded on the narrow tires normally used on road bikes. In the automotive realm, a wheel width of 150-175 mm or more is pretty normal, and the tires that will go on it will be at least 25-30 mm wider than the wheel... that in turn means that when pressurized, the forces acting near the bead have a larger normal component than a tangential component. But of course, automotive tires are rarely very high pressure. Many are kept between 35 and 50 psi. That said, there are still use cases where the mechanical load on the tires can change the calculus there (e.g. off-roading, rock climbing), which is why things like beadlock setups exist. Even on a mountain bike or gravel bike, the wider difference between rim width and tire width along with the generally lower pressures afforded by tubeless equals some feasibility... But with road tires, there's barely 5 mmm of difference between tire width and wheel width, meaning that the forces under really high pressure aren't as well aligned to the normal of the rim lip. That also explains why the max pressure rating is ~72 psi. In the before times when inner tubes were still the only game in town, you had hookless wheels as well, but you had the tube pushing against the bead from the inside, so it helped to keep things seated.

Si teaches things better than most of university professors.

It's great that more rim manufacturers are getting on board with dimension and pressure standards. But to complete the equation, tire manufacturers must also join the party and to date, few have.

I am only just getting used to the concept of tubeless tyres and yet here we are with this new hookless technology.

I just bought enve 65 foundation hookless wheels. I’m having trouble finding hookless tires. I know pirelli is hookless compatible until 73psi but I don’t want to run pirelli. Does anyone have a list of hookless tire available on the market right now?

Hello everyone. I have bought zipp 303s wheels with this system in february 2020. my experience is good. The only drawback is that there are only two tyres on the market for this system. They are schalwe pro one tle and pirelli zero tlr. The first one lasted 1300 kms on the rear tyre and I had to change it, the second one with 1300 kms I have removed it to finish wearing it on the front wheel. The front tyre has 2800 kms and is still half life. For the reason of the high wear I tried with Pirelli and I think it's better, it's heavier, but I think I will mount schalwe in front 25 and pirelli in the back 28. In short it is a great wheel, weight 1540grams that you can ride with a good tyre the pirelli but this limitation of nerumaticos in the market is the only thing that worries me. if it is true that there are two but schalwe weighs 260grams but it wears out very soon and it is worth 55euros.

I'm really considering the Firecrest 303 hookless and run a 28mm tire. My only concern... will this be ok for heavy riders that are 85kg and over?

For those thinking that a big bump could easily increase the pressure in a tire to or past Zipp's stated 145 psi (to get a tubeless tire on their hooked rim to blow off), you're wrong. Let's say you inflated your road tubeless tire on that Zipp hookless rim to 100 psi. You'd have to completely compress 31% of your tire (basically 1/3 of your tire) to zero volume to see the tire pressure increase to 145 psi. At more normal road tubeless pressures, say 70psi, you'd have to compress over 51% of your tire to zero volume to get a blow-off. What all that means is that there's no bump that's going to cause a blow-off. A bump could damage the rim so that air pressure is lost, but that's not a blow-off.

Hookless rims didn't come 7 years ago, it was the other way around. Hookless rims were the standard until about the 70's, and then they slowly disappeared because of the non-rigid/flexible tires. Now they've come back because of the tubeless tires

#askGCNtech Si mentioned that the optimal pressure for most road riders was much lower than they think. It would be great if you could explain this!

So how come Conti 5000TL state on the sidewall that they can only be used with a hooked rim?

It feels like a development in marketing and lower manufacturing cost

Informative video. I'll stay with clinchers until they are no longer manufactured which will not be in my lifetime because I'm old.

I'm currently using hookless rims and so far not had a problem. One thing you forgot to mention is that Pirelli state on their website that their P ZERO™ Race TLR SL 24-622 and P ZERO™ Race TLR SL 26-622 are NOT compatible with hookless rims.

Has there been any testing around punctures and how well a hookless rim holds a tyre if you suddenly get a flat? I use hooked tubeless, and unseating the bead is really difficult which gives me a bit of confidence that if I’m descending and get a big slash in my tyre I won’t be rolling on carbon before I have the chance to stop.