How much pressure is dangerous?

[heffly]

Thank you for collecting nails. I knew those car tires where good at something...

 

[TourNut]

We've got these little comb like ridges, oriented perpendicular to direction of travel, at the sides of and between the lanes sometimes. All they do is make a buzzing noise in a car, and they're nearly unnoticeable on a bike. You can feel them but can't really hear them with ear plugs in. They are far too shallow to cause a control problem. the reflective "Botts Dots" are actually more noticeable, especially with zero PSI in your tire. What was Michigan thinking?

Wasn't in Michigan , I was 5 minutes west of the Mississippi River , I-80 , Iowa when the ChatterBox Theft module suddenly TURNED OFF my ignition - no warning . I was trying to get off / out of traffic at approx 45° angle , but I felt tires get deflected on the really deep cut rumble strips so that the bike was aligned roughly with the road pavement edge , although I was still traveling the roughly 45° into the relatively flat weeds , which was the last thing I remembered . Do not remember the "hit" - concussion turned off memory until moment paramedics were coaxing me off my feet & getting me into ambulance . I was surprised how many people were all around in what seemed to me like about 1 second of time .

Point here is that those rumble strips CAN deflect you , I was surprised by it in that last split second as I expected to just ride out into a flat area of weeds & stop .

Tires were PR3 -f , PR4 - r then

since then , BT 45 & GYTT

 

[dduelin]

Tires are very very strong in regards to pressure holding capacity. They have to be able to withstand great pressure spikes when hitting sharp edged surfaces even when fully loaded. In the old days when I was at Bonneville salt flats we would inflate tires to 80-100 psi to reduce rolling resistance. I would doubt you could hurt your tire from any over pressurization that was anywhere close to normal. I would worry much more about running under-inflated tires as heat can build up rapidly.

When I met the woman who become first wife and later my only ex-wife I was working as a car tech. She came by work one day driving her Toyota Corolla and being ever the gentleman I offered to check her car over. On my shirt pocket pencil tire gauge all 4 tires were over 50 psi. We had a truck gauge calibrated to 120 psi so out of curiosity I check one and it had right at 100 psi. All four had between 90 and 110 psi! Her dad said later that he inflated the tires (without a gauge) trying to remove the bulge in the sidewall above the contact patch. Well and good except the car had radial tires and his experience was only with the then common bias ply tires. This was in 1980 when most tires were still bias ply that did not have the bulging sidewall above the contact patch. She didn't know any different and drove the car for a while with 100+ psi in the tires.

 

[Kevcules]

When I met the woman who become first wife and later my only ex-wife I was working as a car tech. She came by work one day driving her Toyota Corolla and being ever the gentleman I offered to check her car over. On my shirt pocket pencil tire gauge all 4 tires were over 50 psi. We had a truck gauge calibrated to 120 psi so out of curiosity I check one and it had right at 100 psi. All four had between 90 and 110 psi! Her dad said later that he inflated the tires (without a gauge) trying to remove the bulge in the sidewall above the contact patch. Well and good except the car had radial tires and his experience was only with the then common bias ply tires. This was in 1980 when most tires were still bias ply that did not have the bulging sidewall above the contact patch. She didn't know any different and drove the car for a while with 100+ psi in the tires.

That's crazy and scary at the same time. Amazing how much pressure some tires can manage to hold and not explode.

I had a good laugh at my 18 yr old son and his friend a few years ago. They borrowed my 4 wheeler and when I got home, I saw it was parked in the garage but it was sitting up funny. It looked like the tires were really round on the bottom. I checked the air pressure and it was about 25lbs??? I asked the two teenagers what happened and they said the tires looked low so they wanted to do me a favor and top them up. "Why so high I said?" because they only call for 3 to 5 lbs. They said that's what the tire said. lol I pointed out to them that it says "maximum pressure to seat the bead" is only for tire install and not the running pressure.