eduskator

Hey guys,

Long story short, I am getting a set of Schwalbe Pro Ones for my 2021 season and I was wondering if some of you had measured the width difference between a tire on a hooked rim and the same tire on a hookless rim to see what's the actual difference?


Giant says that a 25c tire on a hooked rim has the same width than a 23c tire on a hookless rim, so I guess that a 25c tire on a hookless rim must be close to 28mm. My actual tires (came with the bike) are the following: CADEX Road Race, tubeless, 700x28mm (25c). I checked on the sidewall and it's indeed a 700x25c, but it seems like they are 28mm ''in reality''.

I am wondering if I should get 700x25c or 700x28c. What do you think?

WhyFi

There are going to be a lot of differences here and there - internal rim width, hookless vs not, different tire manufacturers/models/generations, etc.

The current Schwalbe Pro One Evo Addix are meant to measure out to their nominal size on 19mm internal width rims, though. Find out the internal width of your rims and adjust the estimate from there.

dmanthree

What kind of rims do you have? I'm a retro-grouch and see no point to hookless rims. IMHO...

Dean V

Not exactly sure what the question is, but will say that 28mm Schwalbe Pro1 on my Enve 4.5AR rims are around 32mm wide.

eduskator

Giant SLR-1 wheels (hookless - 19.4mm). I was asking if a specific tire on a hooked rim had a different width than on a similar rim (same size, same width) but hookless design because Giant says (see below) that I have 28mm tires, but the actual size of my tires are 700x25c. If I get 700x28c instead, will I actually have wider tires than 28mm?

• Tires
  CADEX Road Race, tubeless, 700x28mm (25c), folding

WhyFi

Again, it depends. Where is the manufacturer measuring internal width - between the hooks or under them? Which tire manufacturers? Etc. What I can say is that the nomenclature that Giant is using for those tires isn't standard and they're confusing the matter instead of clarifying it.

Regardless, the Schwalbe Pro One Evo Addix are made for 19mm int width rims, making them very narrow by the standards of only a couple years ago, and should measure out close to their nominal size on your wheels. Will the POEA in 28mm be wider than 28mm on your rims? Maybe a hair. Is your clearance that tight that it wouldn't accommodate 29 or 30mm actual? If you've got the room, just try it out. I only got 2.5k-3k miles out of my rear POEA, so if try them out and if you decide to go with the 25mm next time, take two or three months to get their tread life out of 'em and move on.

Sy Reene

I'm a bit confused on the premise. Cadex is its own brand of wheel and tire (or is this a Giant company/subsidiary?).
URL assist:
https://www.cadex-cycling.com/us/hoo...rim-technology

eduskator

Giant owns Cadex.

My 2021 TCR came with Giant SLR1 rims & Cadex Road Race tires. My 2018 TCR came with Giant SLR1 rims & Giant Gavia Race 0 tires.

Both rims and tires must come from the same place and be close to similar.

eduskator

Thread update: I ended up getting the 28mm.

If anyone is curious, they measure 28.7mm inflated at 70psi on my hookless rims (19.4mm inner width).

I did not get a chance to measure the actual width of my previous tires, but the new ones a lightly wider for sure. It feel a lot better to run 70psi than 85psi I was running with the 25c.

LucVDE

I've exactly the same rims and just like you 3 years ago hesitating between 25 and 28 for the upcoming tire replacement. What's your experience? Are the 28's really so much better as everyone says? My concern about them is the aero penalty on the rather small rims. Most people who put wider tires have also wider rims than those SLR1's.

eduskator

It's definitively better for me. Not in terms of performance (I can't tell the difference honestly, it's marginal for us mere humans), but in terms of comfort. The added comfort to me easily outweighs aero penalty (if any, it will be unsubstantial).

I am still using 28mm tires, but I now have different rims (hooked / 21mm internal width). They inflate at 29mm on them. Pressure is a little higher (+5 PSI) too.

cyclezen

Realized Rim Internal width should be the deciding factor on actual overall tire width...
so, from old school 17 internal with hooks moving to hooked 19 internal width and then 19 hookless and then 21 should show some increase in tire width.
Because a tire has a defined width (if laid out flat), allowing the tire to spread wide a bit more, the tire height on the rim, would also be some degree 'lower'; meaning smaller overall circumference.
Having a 'wider tire' of such a small degree isn;t the point... The point is to potentially have a more 'aero' air flow across the tire/rim front and around the side and back of rim (dependent on the rim 'profile). Both HED and ZIPP studies in the very early 2000s indicated that a 'toroidal' form to the rim profile had the lowest resistance and best air flow. AND that deeper rim profiles weren't necessarily 'more aero' - that the toroidal rim sides need to be designed for each rim width - AND, in fact, a less deep rim with toroidal form had much better 'aero' .
A side benefit of slightly increased rim/tire width is slightly larger contact patch, and the lower running pressures means the tire/wheel combination absorbs the very small, frequent road irregularities, which lowers rolling resistance - A faster wheel' - very measurable and also rider discernible.
Seems though, as usual with mankind, we're on a pendulum swing of 'wider is better'...
I'm waiting to see studies which show aero improvements of 30 or 32 tires over 25 or 28 on a 21 internal rim. And of course, we now also can buy road wheels with 23 internal width rims... BUT are they having a true Toroidal rim depth profile? ???
not all deep/aero rims are equal... And, of course, spoke count has a great affect on 'aero', especially the front wheel....
Ride On
Yuri
EDIT: https://apps.calif.aaa.com/aceapps/authenticate2/login
https://www.bikeradar.com/advice/buy...els-lab-tested - go down to the HED JET 6.9 - which is a carbon 'faired' wheel...
https://bikerumor.com/review-hed-van...ndle-any-road/
I'm NOT trying to be a HED saleman, but their studies and resulting products are hard to dispute - they've been my go-to wheels since 2007... but now hard to justify the cost, purely because I'm so SLOW now, nothing much helps... LOL !

PeteHski

For most riders the improvement in ride quality and grip are likely to be more important than any aero differences between them. Lower pressures are also a major advantage when running tubeless sealant.

cyclezen

Yeah Totally, 'comfort' is always an important criteria. But this can also vary quite a bit depending on the rider, so 'most' might be a little strong....
Rider mass and , to some extent, ride 'style' contributes a lot to the experience/process...
A rider of my weight, 145 ish lbs, is going to experience tire 'performance' based on tire size and running pressure different than someone even at 170 lbs, and that'll be way different from another who is 200+, and different from someone 120 ish lbs...
I'm constantly made of aware of this in the so many threads which talk about so many things, experiential, like ride quality, bike/tire performance, etc, where a 'comment' is made WITHOUT ANY reference to rider dimensions. There's often no way to put a comment into proper context, because that info is lacking...
so, me, riding my 23s at 80 psi, on a 19 in internal wheel, might be similar to another, larger rider riding their 25s at 100 psi...
it's great when a poster adds pertinent info...
anyway... hook vs hookless - interesting if data comes for any performance difference... difference in ease of mounting? prolly. My very limited experience with my wheels doesn't seem an issue with 'hooked'.
... thread has prompted me to go thru both HED and ZIPP sites (and other places) for any new info on wheels/rims...
Ride On
Yuri

PeteHski

If you are riding competitive TTs then the aero advantage of slightly narrower tyres might come into play. Otherwise I doubt it matters. Whatever you weigh, lower pressures are going to provide an advantage if running tubeless. Lighter riders just get more of an advantage. I saw that Paris Roubaix was won this year on 32 mm tubleless tyres @50 psi with a solo 60 km break. So any aero loss can't have been very significant. If it wasn't for the cobbles he probably would have used 28mm tyres, but still... At my level I'll take the lower pressures, grip, comfort and versatility of the 32 mm tyres and not worry about the aero penalty (if any).

eduskator

Indeed. And the extra puncture resistance / auto-seal function. Those are the 2 reasons why I run tubeless and 28mm.

cyclezen

True, about Paris-Roubaix - from BikeRadar : "...32mm road bike tyres look to be the new defacto standard for Paris-Roubaix. Movistar Team, Groupama-FDJ, UAE Team Emirates and Ineos Grenadiers were all on 32mm wide Continental GP5000 S TR tyres. Pushing further, some riders, such as Bahrain-Merida's Fred Wright, used a 34mm wide GP5000 AS TR."
But Many riders don't have those punishing conditions on their ride. We Are talking 'road', not gravel... And our roads in Santa Barbara County are some of the scrappiest,'Roubaix-ish' roads I've ever ridden (US,Can & Continental Europe), so 'comfort' and making it thru withou incident is important. Hence I've always tended to the lower inflation pressures suited for any tires - I rode high quality race tubulars predominantly until just after 2000...
But I also like and ride roads which have constant ups & downs, and often longer ups (with the resulting euphoria of long 'downs'). Hence my attention to rotational mass.
The advantages of a good rolling tire of light weight on good wheels became extremely apparent to me in the late 60's, and I've never found reason to think different. I had, for many years, kept a 'training log', which contained all my rides - along with notes on ride effort and purpose... I'm old and over all that, but I still desire a 'nice ride'.... The most apparent take away from the training log was, bike mostly didn;t matter (I always had several), but Good Wheels and Tires made a constant, consistent and very apparent difference.
The point... If 32mm works for you - Great ! But it may not be necessary for some others... I Still ride 25mm and a few 23s left in my stock supply... In past years I would go thru 4-5, 6 tires a season, with sewups - more... Now down to 3 -4 / yr... A fast riding wheelset can also be 'comfortable'.
Anyway, I would suggest each rider make their own evaluation as to what 'comfort' and 'performance' is...

May I ask, if not too personal a question, "How much do you weigh?"

I watch a LOT of road racing, cyclocross and mtb... always listening also - hook vs hookless - heard comments from various sources that some issues with racing tubeless is inadvertent tire blow-off due to hitting rough spots... of course racing is pushing the boundaries of tire pressures, to be expected. Prolly reasonable 'average rider' with more comfort pressures is not an issue... a hooked rim might still offer a bit more holding power ? don;t know...
Ride On
Yuri