tire plugs and math test

[Coyote Chris]

I need someone with a masters degree in math.  If I plug a tire with a 3/16th diameter hole, and pump up the tire to 42 pounds per square inch, then the actual force trying to shove that plug out when the bike is at rest should be 42 psi  for one square inch times by the actual area of the hole, which if my fifth grade education didnt fail me is .02759 in. so the actual pounds on the plug at rest is .1 lbs or 1.6 ounces?  Then we have to add the centrifical force when the bike is moving?????  Has anyone ever had a plug fly out of a tire?

Area of a 3/16 diameter hole  =Pi x radius squared = 3.14 x .09375 squared= .02759 sq inches

 

[zorlac]

0.027611654181941542134925576610855 sq in * 42psi = 1.1596894756415447696668742176559 lbs of pressure.  :

"Has anyone ever had a plug fly out of a tire?"

Yes, on my car once.

 

[coffee_brake]

0.027611654181941542134925576610855 sq in * 42psi = 1.1596894756415447696668742176559 lbs of pressure.  :

"Has anyone ever had a plug fly out of a tire?"

Yes, on my car once.

Me too, the Connie's rear tire threw a plug while underway. Now THAT was a skittery, scary ride to the nearest driveway...which happened to be a Chevy dealership, where a great older mechanic loaned me the portable air tank and gave me some water so I didn't pass out filling the tire (with its second plug, which also blew out in the driveway that very afternoon) with the hand pump. In July, in mid Georgia. In full gear. My hero of the whole freakin' year.

I learned a lot about plugging tires with too big a hole, and then I ran a tube in that tire with no further problems till I brought it home on the cords after this year's National.

Yes I run plugged tires, I get so many roofing nails in this town that if I didn't run plugs, I couldn't afford to ride. But this was a self drilling machine screw and it tore a mean big hole in my Metzler.

 

[2linby]

I need someone with a masters degree in math.  If I plug a tire with a 3/16th diameter hole, and pump up the tire to 42 pounds per square inch, then the actual force trying to shove that plug out when the bike is at rest should be 42 psi  for one square inch times by the actual area of the hole, which if my fifth grade education didnt fail me is .02759 in. so the actual pounds on the plug at rest is .1 lbs or 1.6 ounces?  Then we have to add the centrifical force when the bike is moving?????  Has anyone ever had a plug fly out of a tire?

Area of a 3/16 diameter hole  =Pi x radius squared = 3.14 x .09375 squared= .02759 sq inches

Academia does not always bode well with physics. No doubt the plug itself is significantly larger that the 3/16" of an inch than hole in which it sits is. Assuming it is perfectly round lets say, for the sake of argument, the plug diameter is closer to 1/2" this then would in a static translation equate to a direct pressure on the top or surface area of the plug itself of 8.2425 lb. Significantly higher than that of a 3/16" plug. However the pressure on the grip on the plug itself as related to the friction holding the plug to the surface area of the tire itself on the shaft of the plug could only be determined by the thickness of the thread depth and then and only then can the direct pressure of the surface and contact surface, The shaft pressure,  be calculated to determine the "strength" of the hold. If in fact this was the intent of the posting in the first place. 

And in my expereince, no I've never "thrown a plug".

 

[greg.m784]

I need someone with a masters degree in math.  If I plug a tire with a 3/16th diameter hole, and pump up the tire to 42 pounds per square inch, then the actual force trying to shove that plug out when the bike is at rest should be 42 psi  for one square inch times by the actual area of the hole, which if my fifth grade education didnt fail me is .02759 in. so the actual pounds on the plug at rest is .1 lbs or 1.6 ounces?  Then we have to add the centrifical force when the bike is moving?????  Has anyone ever had a plug fly out of a tire?

Area of a 3/16 diameter hole  =Pi x radius squared = 3.14 x .09375 squared= .02759 sq inches

Academia does not always bode well with physics. No doubt the plug itself is significantly larger that the 3/16" of an inch than hole in which it sits is. Assuming it is perfectly round lets say, for the sake of argument, the plug diameter is closer to 1/2" this then would in a static translation equate to a direct pressure on the top or surface area of the plug itself of 8.2425 lb. Significantly higher than that of a 3/16" plug. However the pressure on the grip on the plug itself as related to the friction holding the plug to the surface area of the tire itself on the shaft of the plug could only be determined by the thickness of the thread depth and then and only then can the direct pressure of the surface and contact surface, The shaft pressure,  be calculated to determine the "strength" of the hold. If in fact this was the intent of the posting in the first place. 

And in my expereince, no I've never "thrown a plug".

I think i just sprained my brain.

 

[bobct]

I have posted this before but think it deserves a honorable remention here. Kit is a little large because of the pistol style insert tool. My 1000 mile Azaro rear had a screw in it. A mechanic friend of mine had a vulcanizing tire plug kit. The plug is black and you add a liquid vulcanizing material to the plug. It actually becomes permanent part of the tire. He said if it didn't leak after a few minutes it would hold. These are used at race tracks (cars) and by Police Depts. Kept an eye on pressure for the first few weeks, I used the tire for the rest of the season without any leakage. Napa Auto Parts Part#BK 7101028 for $90 (a little pricey). For anyone using plugs I would highly recommend but take no responsibility for product use or abuse.

 

[zorlac]

I need someone with a masters degree in math.  If I plug a tire with a 3/16th diameter hole, and pump up the tire to 42 pounds per square inch, then the actual force trying to shove that plug out when the bike is at rest should be 42 psi  for one square inch times by the actual area of the hole, which if my fifth grade education didnt fail me is .02759 in. so the actual pounds on the plug at rest is .1 lbs or 1.6 ounces?  Then we have to add the centrifical force when the bike is moving?????  Has anyone ever had a plug fly out of a tire?

Area of a 3/16 diameter hole  =Pi x radius squared = 3.14 x .09375 squared= .02759 sq inches

Academia does not always bode well with physics. No doubt the plug itself is significantly larger that the 3/16" of an inch than hole in which it sits is. Assuming it is perfectly round lets say, for the sake of argument, the plug diameter is closer to 1/2" this then would in a static translation equate to a direct pressure on the top or surface area of the plug itself of 8.2425 lb. Significantly higher than that of a 3/16" plug. However the pressure on the grip on the plug itself as related to the friction holding the plug to the surface area of the tire itself on the shaft of the plug could only be determined by the thickness of the thread depth and then and only then can the direct pressure of the surface and contact surface, The shaft pressure,  be calculated to determine the "strength" of the hold. If in fact this was the intent of the posting in the first place. 

And in my expereince, no I've never "thrown a plug".

I think i just sprained my brain.

Nah, Bob totally ignored the Centrifugal force effect on the mass of the plug during a high speed run. 

 

[S Smith]

I need someone with a masters degree in math.  If I plug a tire with a 3/16th diameter hole, and pump up the tire to 42 pounds per square inch, then the actual force trying to shove that plug out when the bike is at rest should be 42 psi  for one square inch times by the actual area of the hole, which if my fifth grade education didnt fail me is .02759 in. so the actual pounds on the plug at rest is .1 lbs or 1.6 ounces?  Then we have to add the centrifical force when the bike is moving?????  Has anyone ever had a plug fly out of a tire?

Area of a 3/16 diameter hole  =Pi x radius squared = 3.14 x .09375 squared= .02759 sq inches

Academia does not always bode well with physics. No doubt the plug itself is significantly larger that the 3/16" of an inch than hole in which it sits is. Assuming it is perfectly round lets say, for the sake of argument, the plug diameter is closer to 1/2" this then would in a static translation equate to a direct pressure on the top or surface area of the plug itself of 8.2425 lb. Significantly higher than that of a 3/16" plug. However the pressure on the grip on the plug itself as related to the friction holding the plug to the surface area of the tire itself on the shaft of the plug could only be determined by the thickness of the thread depth and then and only then can the direct pressure of the surface and contact surface, The shaft pressure,  be calculated to determine the "strength" of the hold. If in fact this was the intent of the posting in the first place. 

And in my expereince, no I've never "thrown a plug".

I think i just sprained my brain.

Nah, Bob totally ignored the Centrifugal force effect on the mass of the plug during a high speed run. 

Probably also should account for any adhesive used or vulcanization that will occur.

 

[worncog]

Plus the centrifugal forces are variable and the retentional friction forces of the tapered entry into the hole... Too many variable to venture into the headache zone.

With the verical challenges already in place with a proper functioning tire set, I carry a plug kit that only uses mushroom headed plugs. The kit costs a bit more, around $40 if memory serves correctly, and included an insertion gun for proper application in the tire. The kit fits nicely in the nook of the right saddlebags and I also carry a mini-compressor tucked into the tail section for inflation. Call me a boy scout, but I also have a mountain bike pump velcroed in the sadllebag. Carrying this kit is not a save all, but it gives me the confidence that the plug should not migrate out as I am tilted over in a high speed sweeper out in the middle of nowehere where it will take weeks to locate my withered body in the ditch before the snows fall.

 

[bigjoeva68]

Does it matter if you are using summer air instead of autumn air?  :rotflmao:

 

[vigilante]

Maybe you should add the atmospheric pressure to this simple little formula we are concocting.  What altitude are you at.

 

[Coyote Chris]

Good point.  In the frame of reference of the plug, what would be the difference from leaving Spokane at 2400 ft and going over a 10,000 ft mountain pass?
I am now working on a formula to find out the pressure on a mushroom head plug, which means a friction analysis on the underside of the rim of the plug on the inside of the tire....where is that calculus book...it cant be this hard....

 

[zorlac]

If I need another hole in my head and then later feel the need to plug it, what type plug should I use?

 

[slybonesjesse]

rocks

 

[Outback_Jon]

Good point.  In the frame of reference of the plug, what would be the difference from leaving Spokane at 2400 ft and going over a 10,000 ft mountain pass?

If a Concours leaves New York City traveling west at 2:00pm with a sticky rope plugged tire, and another Concours leaves Chicago traveling east at 3:30pm with a mushroom style plugged tire, at what point will they need to change their oil because they used energy conserving synthetic instead of motorcycle oil?


)

 

[bigjoeva68]

If a Concours leaves New York City traveling west at 2:00pm with a sticky rope plugged tire, and another Concours leaves Chicago traveling east at 3:30pm with a mushroom style plugged tire, at what point will they need to change their oil because they used energy conserving synthetic instead of motorcycle oil?

Were they using summer air or autumn air?