tire pressure
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Topic author - Posts: 13
- Joined: Fri Jan 18, 2019 3:32 pm
- First Name: Glenn
- Last Name: Allen
- Location: Northport
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tire pressure
what is tire pressure 0n 30 by 3 tire
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- First Name: Allan
- Last Name: Bennett
- * REQUIRED* Type and Year of Model Ts owned: 1912 van, 1917 shooting brake, 1929 roadster buckboard, 1924 tourer, 1925 barn find buckboard, 1925 D &F wide body roadster, 1927LHD Tudor sedan.
- Location: Gawler, Australia
Re: tire pressure
I run at 60 psi. Certainly never less than 55.
Allan from down under.
Allan from down under.
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- First Name: John
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Re: tire pressure
agreed at 60
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- First Name: Steve
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Re: tire pressure
I run at 65 front (30 x 3) and 70 rear (30 x 3½), so if they lose five pounds before I check the pressure they're still OK.
The inevitable often happens.
1915 Runabout
1923 Touring
1915 Runabout
1923 Touring
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Re: tire pressure
The early treatises call for 20 pounds per inch of tire on clincher rims. That's 60 front and 70 rear.
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Re: tire pressure
I called Lucas Tire and a real friendly reply on 30 X 3 1/2 tire pressure was 65 PSI. I've been running 50 or years so I'll have to bring mine up a little.
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Re: tire pressure
I suspect letting the pressure get too low was why I lost a tire a couple of years ago. I walked back along both sides of the road and I never did find that tire.
The inevitable often happens.
1915 Runabout
1923 Touring
1915 Runabout
1923 Touring
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- First Name: Bob
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Re: tire pressure
Hi, Neighbor in Northport;
The reason we need to run high pressure in clinchers is to avoid shearing the air valve off the inner-tube. Higher pressure forces the rubber clinchers more tightly against the rim, thus preventing tire slippage. If the tire slips along the rim (and this tendency is strongest during heavy braking), the inner-tube gets stretched at the point where the air-valve pokes through the rim and that can cause it to tear apart. This problem is much more prevalent in the case of the rear tires because they are subjected to the fore and aft loads of acceleration and braking. Not so, the front wheels, the most significant problem of which is the kind of excessive side-load you get when rounding a corner at too high a speed (which is not only bad for the tires, but for the wooden spokes as well).
Point is, you have some "wiggle room" when it comes to deciding on the proper inflation pressure of your front tires, and if you run them at, say, 50 pounds instead of 60 pounds, the front passengers will feel the car riding much more smoothly (and I run my driver-side front tire a little softer than the passenger-side front tire in an effort to counteract the natural tendency of a Model T to pull to the right on a crowned street, so I'm working with three different inflations). But as always, take corners slowly so as to avoid peeling the tire off the rim or shattering the spokes.
There's not a whole lot we can do about reducing the acceleration and braking impulses at the rear wheels. In a Model T, those forces are already minimal compared to most any other kind of car and reducing them further is not really possible. The usual vacuous advice applies and all you can do is inflate to the recommended pressure and drive gently.
Your Neighbor in Commack
The reason we need to run high pressure in clinchers is to avoid shearing the air valve off the inner-tube. Higher pressure forces the rubber clinchers more tightly against the rim, thus preventing tire slippage. If the tire slips along the rim (and this tendency is strongest during heavy braking), the inner-tube gets stretched at the point where the air-valve pokes through the rim and that can cause it to tear apart. This problem is much more prevalent in the case of the rear tires because they are subjected to the fore and aft loads of acceleration and braking. Not so, the front wheels, the most significant problem of which is the kind of excessive side-load you get when rounding a corner at too high a speed (which is not only bad for the tires, but for the wooden spokes as well).
Point is, you have some "wiggle room" when it comes to deciding on the proper inflation pressure of your front tires, and if you run them at, say, 50 pounds instead of 60 pounds, the front passengers will feel the car riding much more smoothly (and I run my driver-side front tire a little softer than the passenger-side front tire in an effort to counteract the natural tendency of a Model T to pull to the right on a crowned street, so I'm working with three different inflations). But as always, take corners slowly so as to avoid peeling the tire off the rim or shattering the spokes.
There's not a whole lot we can do about reducing the acceleration and braking impulses at the rear wheels. In a Model T, those forces are already minimal compared to most any other kind of car and reducing them further is not really possible. The usual vacuous advice applies and all you can do is inflate to the recommended pressure and drive gently.
Your Neighbor in Commack
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Re: tire pressure
Looking at my tyres (tires) they show slight signs of under inflation wear pattern. I would guess that increasing the pressure
from 69 to 65 PSI would cure this. But Boy oh Boy, I get very nervous pumping up tyres to 60 due to the poor quality Tubes we have to tolerate these days. Tube issues is another pet hate of mine. Alan
from 69 to 65 PSI would cure this. But Boy oh Boy, I get very nervous pumping up tyres to 60 due to the poor quality Tubes we have to tolerate these days. Tube issues is another pet hate of mine. Alan
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Re: tire pressure
Should read from 60 to 65
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Re: tire pressure
55-65
But if less then 55 youl get good a fixing flats
But if less then 55 youl get good a fixing flats