cormacf

Hi, all. Got my first set of tubeless road wheels (also my first carbon wheels of any sort) -- Reynolds Aero 46 DB running 28mm Hutchinson Fusion 5. 19mm hooked rims.

The Reynolds site gives me a max psi of 100 for that combo, but I'm kind of at a loss about how low I can go without compromising things. Hutchinson's FAQ mentions an app called Connec'tires, which isn't actually available on the Android app store, and I really don't want to sideload an apk from some rando site.

Other pressure calculators give me recommended ranges from 60 (which seems soft) to 70. I'm ~170 pounds, and the bike is around 20. Thanks!

Eric F 

I'm running 80psi in 25mm Contri GP5000TLs. I weigh 180. My best suggestion is to start at 70, and see how it feels. Next ride, try 68 and see if it's an improvement for you. Etc...

urbanknight

I’m running about 10 psi lower than most of the calculators recommend and it works great. FWIW, 65/75 psi on 28mm tires, 21mm rims, 190lb.

rsbob 

I weigh 168 and run my 28 tubeless ContiGP5000s at 70 front 72 rear and they run just fine.

Canker

yeah just play with it, it ain't going to explode. At 170lbs on 28mm I'm a 55/60 guy.

DaveSSS 

Try the pressure calculator at zipp.com. I use it exclusively. You must know your rim's internal width.

GhostRider62

GP5000 TR/S on Zipp Firecrest 303 with 25 mm internal hookless

30mm rear at 55-60 psi

28mm front at 55-60 psi

But I only weigh 207 lbs and my roads suck

KerryIrons

I would be amazed if the OP could tell the difference between 68 and 70 psi, and they probably don't even have a gauge that can accurately and consistently provide a 2 psi difference. The general idea of "start somewhere and go up/down" is good, but 6 psi increments should be the place to start.

bruce19

I used to ride my 23mm clinchers at 130 (rear) and 100 psi (front). I run my 25 mm tubeless at 80 psi (rear) and 70 psi (front). FWIW I weigh in at 186 lbs.

Mtracer

I like the Silca calculator. You need the actual tire width as installed. But of course, go with 28 mm if you have nothing to measure it with. I run GP 5000 S TR 28 mm on 25 mm internal rims for a 30 mm actual width. I'm currently running 66 front, 68 PSI back. I and the bike together come in at about 230 lbs. These pressures are what the Silca calculator came up with for riding on poor condition, paved roads (about 1/3 of the roads I ride on).

NoWhammies

Depending on how in the numbers you want to get, there is always this: https://silca.cc/pages/sppc-form

ZHVelo

I am on hookless which is a little different, but I run 60-65 psi, also on 28mm tubeless.

Also, I feel that going much higher, is slower. Which aligns with what GCN tested, there is a middle range of pressure that is best, with too high and too low pressure being slower. So I am happy to stick to 60-65.

msu2001la

Just another vote for using Zipp or Silca calculators. Zipp seems to deliver slightly lower numbers, but either will get you into the ballpark and then you can adjust from there based on preference.

Chandne

60 PSI seems a bit low for 170 and 19mm rims. I'd guess closer to 70 but use the ZIPP calculator. I'm 175 running 30s on my main bike. The rims are wider (25mm) too will require less pressure, as will the 30mm tires. IIRC, the Zipp calculator calls for 54F/57R. I run 55F/60R. I'll bump it up 2-3 PSI in the rear if climbing.

Okay, I ran your specs through with standard casing hooked tubeless rims and it was 67F/71R.

DirePenguin

I’m 168lbs. and I’ve got Bontrager R3’s (32mm) tires on the hooked rims on my ‘22 Domane and I just dropped from 70psi (which I recently noticed is the max pressure for this tire!) to 60psi based on the Silca calculator.

The ride is more comfortable and I’ve been hitting my highest average speeds on the route I most often ride.

daihard 

I run the Continental GP 5000 AS TRs (28 mm) at 75 PSI. I think I can lower it to 65-70 PSI to get even more comfortable. I weigh 155 lbs.