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Tire Pressure vs Contact Patch

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  #1  
Old 06-18-2022 | 05:06 PM
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Default Tire Pressure vs Contact Patch

The thread on tar snakes got me thinking about how much tire is on the road and how resistant the tire would be to flexing over sand and tar strips verses the tires air pressure.
I'm always hearing of people going over the manufacturers recommend air pressure to try and get more milage out of a tire.
More contact area means better traction wet and dry, shorter stopping distance and a nicer ride.

 
  #2  
Old 06-18-2022 | 05:11 PM
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Any information on stopping distance based on the various inflation pressure? It seems to make sense that more tread contact would mean better traction and shorter stopping distance. But too low of pressure means the tire would deform under those conditions. So I wonder where the sweet spot it?

Paul
 
  #3  
Old 06-18-2022 | 05:12 PM
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Whats your point?

15PSI is a flat tire!!!!!
NO control!!!!
Bead comes off the rim........crash!

Mfg recommended tire pressure!
I run 36 front, 40 rear.
 

Last edited by MURPHCC1; 06-18-2022 at 05:14 PM.
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  #4  
Old 06-18-2022 | 05:31 PM
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Originally Posted by MURPHCC1
Whats your point?

15PSI is a flat tire!!!!!
NO control!!!!
Bead comes off the rim........crash!

Mfg recommended tire pressure!
I run 36 front, 40 rear.
I'm saying decide what is right for you.
This chart is for truck tires. We air them down to go into the desert, much better traction and more resilient to punctures, and no, at 15lbs you won't break a bead. My ATV I run 4 lbs and never lost a bead. 15 psi you may over heat/over flex a tire causing it to come apart and crash.
I'm just trying to show that people that bump there air pressure to 45/50 lbs to gain tire life are sacrificing something.
 
  #5  
Old 06-18-2022 | 05:36 PM
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Did someone bring that up about Harley Davidsons?
 
  #6  
Old 06-18-2022 | 05:44 PM
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Originally Posted by MURPHCC1
Whats your point?

15PSI is a flat tire!!!!!
NO control!!!!
Bead comes off the rim........crash!

Mfg recommended tire pressure!
I run 36 front, 40 rear.
That is unless you are riding an old rigid Harley. Then that is the recommended pressure from the MOCO.
EDIT, found it................The riders manual for the 1948 Panhead shows the tire pressure for a solo rider and one passenger at 12lbs front and 16lbs rear for the 5.00 x 16 tire
 

Last edited by perki48; 06-18-2022 at 06:04 PM.
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  #7  
Old 06-18-2022 | 06:00 PM
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Put what the owners manual says.. Same with cars on the door post.

When you actually wear a flat, it fills squirrelly in the corners. I'm an expert at that. No chicken strips for me.
 
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  #8  
Old 06-18-2022 | 07:42 PM
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Those tire PSI statistics are really great . . . for 4 WHEEL VEHICLES. Motorcycle tire contact patch on the road changes in curves. Just think about it. Motorcycle tire tread is round. Cars, trucks, etc tread is FLAT. Motorcycles have more dynamics in play than yer Dad's Buick.
 
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  #9  
Old 06-18-2022 | 07:54 PM
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Originally Posted by s-glide76
I'm always hearing of people going over the manufacturers recommend air pressure to try and get more milage out of a tire.
People do lots of stupid-*** things to try to squeeze more mileage out of a tire, like overinflating them, or even using car tires that don't have the proper safety bead for a motorcycle rim.

Inflate it to the proper pressure.



​​​​
 
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  #10  
Old 06-18-2022 | 08:05 PM
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Right.
I don't overthink tires or brakes.
 


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