Hookless rims (Giant SLR1)

dahat

Any user experience of tyre pressure for tubless GP500 for these rims? Giant guidelines indicate 66 psi which seems savage low.

22.4 internal width

28 c tyre

100kg rider

I run clinchers at 95/90 for 28mm so 66 doesn't seem right.

lissard

I have the same wheels with 32mm tyres and was struck by the exact same thought. I guess tubeless is just way lower pressure in general. For what it's worth they roll just fine and give a very comfortable ride. No experience of what GP5000S TR feel like yet.

mamax

Same wheels and recommended 61 for 80kg but I go to just below 65, play around with it and see, I just find a few psi above better for me

I'm at 50psi on the gravel bike with 38mm tires and same internal width

CantGetNoSleep

I don't have the same wheelset (have a Zipp 303S - also hookless and 23mm inner width) but I run 28mm Schwalbe Pro One's at 55psi front / 60psi rear (I'm about 75kg). I have no issues and certainly don't feel like the pressure is increasing rolling resistance. I've used various different online pressure calculators and all come out similar. Think 70psi is the max for my rims

dahat

Thanks for the reassurance folks.

A starting point will be 70/72 then see how that feels ,I'll also be racing these so need to be confident in my set up.

Macy0161

You could run inserts as a bit of insurance - I used vittoria airliners last season (ride flat capability an added bonus racing).

CramCycle

There are a few calculators online with guidelines but I remember hearing that the general rule of thumb with hookless was not over 72psi, although over on weightweenies they say the Giant wheels can take more. As with everything, I am going to remain behind the curve and remain on hooked for now but so long as you don't feel any tire squirm in the corners at speed you should be fine.

Bambaata

Giant seem to suggest teir tyres shouldnt be below 70 PSI?

CURRENTLY, for all Giant tyres this minimum (MIN) pressure can now be defined as 70 psi (4.8 bar) for 23C & 25C tyres, 50 psi (3.4 bar) for 28C tyres and 45 psi (3.1 bar) for 32C tyres. Never inflate to less than the MIN pressure.

From https://www.giant-bicycles.com/gb/tyre-pressure

Got myself a TCR with SLR1s that'll b raced this coming year so curious about this myself! Have the Schwalbe Pro One Evo Super Race in 25s to fit yet so a timely topic!

GandhiwasfromBallyfermot

Sorry to hijack this discussion but I have a related question for these wheels. Can they run clincher with the hookless rim? About to pull the trigger on a new Giant but would like to run with clinchers.

dahat

@GandhiwasfromBallyfermot I’ve changed my mind re tubeless & going to run 28mm clinchers on the wheels. I’ve been assured they will be fine.

All going well I’ll have the bike out this weekend so will see how they feel.

CantGetNoSleep

https://www.boards.ie/discussion/comment/121793291#Comment_121793291

Some hookless rims are supposed to require a tubeless tire, but can be run with no issue with an inner tube as long as the tire itself is tubeless.

I'm not sure what the lower pressures would mean for punctures though

mamax

https://www.boards.ie/discussion/comment/121793360#Comment_121793360

They will be fine, but I've 2 seasons done with tubeless and won't be going back to tubes, lower pressure suit me it's way more comfortable and imo better puncture protection.

nilhg

Not directly related to the OPs question but related and worth a look

https://escapecollective.com/thomas-de-gendts-uae-tour-crash-is-a-warning-to-all/

this.lad

I have SLR1's since 2000 on my TCR.

Decided to run them tubeless with the stock giant tyres then on the gp5000 when they gave up the ghost.

Last summer I got a puncture that was beyond repair, the tyre was jaded anyway, and had no spare so I went to the shop for a gp5000 for a race that night, they had none but threw on a Pirelli Zero.

Rode it away in the league race and the following day was looking at it for some reason and is says something to the effect that it's incompatible with booklets systems.

Back into the shop and the guy tells me that my SLRs aren't hookless and all will be ok.

I bought the TCR, basically, because it was the only bike I could get in August 2020 and he couldn't shift it as it was ab expensive bike at the time, though if you offered me the same bike at that money now I'd take it no hesitation, so I wasn't really hung up on the spec etc but once I got it I looked at the website and saw all the specs, powerpro forcexample which i didnt know it had, and definitely saw something on it about booklets rim technology.

Guy in the shop was adamant though. The P Zero is in the shed unused and a GP5000 is in use because I didn't want an accident due to incompatibility. A d there was just something in my head at the time.

I'll check the rim the next time I have a tyre off but it struck me that there's a big risk, with so many technologies floating about, that cross compatibility issues will arise. The shop being liable e.tc. is irrelevant if you're badly hurt or dead.

But if you're buying online, you have to be careful it seems.

secman

"Hookless rims under CPA scrutiny after Thomas De Gendt crash at UAE Tour!

Riders' association president Adam Hansen blames hookless rims for crash while Lotto Dstny defend the set-up ⬇️"