Gravel and Flat Tires

[Michaelr11]

I rode yesterday with friends on a route that included some just repaved asphalt roads. So smooth and a great ride. As part of the repaving, the DOT dresses the shoulders after the asphalt is done, with a mix of dirt and gravel. Some of the gravel ends up on the roadway.

 

Part way through the ride I checked my TPMS (Tire Gard) and noticed that my rear tire had dropped below the front PSI, 43/42 - fully warmed up it should have been around 44 or 45 PSI. My cold PSI is usually around 38/40. About 5 or 10 miles further rear PSI was 40. When I arrived home it had dropped to 38.

 

Examination of the rear tire showed a 1/4 inch stone chip embedded deep into the tire in the middle near one of the sipes. There was a discernable air loss at this spot. This is not the first time I've had a chip of stone pierce a tire carcass.

 

I'm wondering if this is caused by the type of stones that DOT is using for the shoulders, or if it's a downside of riding with soft tires. This is my 3rd or 4th set of PR3 tires; I love them. I guess the only other factor might be just bad luck. That's it, just wondering if others are experiencing sport-touring tires cut by road gravel.

[Mister Tee]

I think there is definately regional differences in asphalt base that causes tires to wear out more quickly. Here most of our base rock is mined alluvium vs. crushed rock, which makes a big difference in tire life and what you observed. I'm not aware of a USDOT pavement specification that addresses sharpness.

 

Funny you mention but I just rode my bike (bicycle) over a section of asphalt slurry on a repaired section of the road and the same exact thing happened. It wasn't a proper rolled pavement repair, just a thick slurry section and it embedded small sharp rocks in my tires. It angered me so much I tracked down the County inspector and complained about it.

[Scribner]

We have a lot of chert used around here on roadsides and gravel roads. It is sharp and can damage tires. Just go faster so it doesn't have time to cut the tire!:-)

[Michaelr11]

Just to be clear, the roads were smooth recently rolled asphalt. Probably some of the best blacktop I've been on. It was just the *&+$*ing stuff they spread onto the new shoulders that got onto the roadway that caused the problem.

 

Stone Chip in tire

 

TPMS display

[NCStephen]

Michael, I will ask around the shop here. I know there are some standards of the mix to be provided but I think the sharpness of the gravel isn't controlled for in this situation. There are some discussions about the stone for chip over tar recovering but not so sure about the crush and run for the shoulder redress.

 

NCS