Running 600x6 4 ply at around 16 psi.
Recently had a flat tire traced to the valve stem getting pulled and ultimately ripped by (I guess) tire slipping on the wheel and pulling the tube with it. Inside of tire had some rubber dust and tube showed chaffing. Other side has valve stem at about a 30 deg angle to "straight out".
So what tire pressures are people running, and anyone else had this problem?
Tire Pressure
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cdoughty
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2066
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Re: Tire Pressure
Even though I understand that the 16 PSI is recommended, I've always been concerned that the "slip" could occur more easily than at higher pressure. Maybe so, maybe no? I normally air to 20 PSI each annual ("Leak Guard" tubes) and "try" to keep close to that -- have never seen indications of a slip. I've gotta admit that 16 PSI sure does make my landings look better(!) and, probably, if I could/would stay off brakes, any "slippage" likely wouldn't be at issue(?). Good question -- will be more thoughts shared, I'm sure. (There's prob at least one IA who would refuse to sign-off for annual with anything more than the "prescribed" 16 PSI 
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6277
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Re: Tire Pressure
16 is way too low for me, barely able to push out of the hangar with more than 1/2 fuel. Rolling resistance is much better with 20+ Tire wear also a factor. 16 might be better for grass strips.
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cdoughty
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Re: Tire Pressure
I never had a problem rolling it around on the ground at 16 psi and had pretty much worn out the tires with one swap to equalize wear.
Moral for me is to check valve stem angle on preflight, especially if you've been running low pressure or doing a lot of aggressive braking.
Moral for me is to check valve stem angle on preflight, especially if you've been running low pressure or doing a lot of aggressive braking.
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hotrodmac
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Re: Tire Pressure
When I first got my 140 2 years ago, it had 20+ PSI on the mains, and I bounced so much on pavement that I normally could log at least 3 landings per stop. Dropped it down to 16 and things got way better. I primarily operate off grass these days though. Tires definitely look slack at 16psi, but I'd be hard pressed to go back to 20. Mac has more landings than I do, so it's probably fair to say your mileage will vary. Use what works for you.
Dropped it down to 16 and things got way better. I primarily operate off grass these days though. Tires definitely look slack at 16psi, but I'd be hard pressed to go back to 20. Mac has more landings than I do, so it's probably fair to say your mileage will vary. Use what works for you.'46 C140
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phil123
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Re: Tire Pressure
32-35 psi then don't touch them for a year 
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bofathillroad
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Re: Tire Pressure
My hangar mate and I both fly 120’s. For a while we couldn’t keep up with the frequent flats / torn valve stems. We both increase the pressure and the problem went away. Find your own sweet spot but 16 psi is way too low if you ask me.