New tires, no info about recommended pressure. put in 20 lbs. they seem firm?
Clincher tires should be inflated to 55-60 psi...
Any less increases the risk of tire to rim slippage and can tear the valve stem.
The balloon tires should be 35 psi.
He is asking about rear tires on the TT truck. Around 60-65.
If the 600X20 tires are anywhere modern they should have the markings on them? The 60-65 Mark suggested sounds about right and if you want a softer ride after they set for a month or so you might try less air? Bud.
I agree with Mark. I'm running 60 psi in my 20" TT Tires. - Matt
I run my 650 X 20's at about 50-55. Bud's correct. There should be a marking on them that tells you the correct pressure. On mine it's in the small print.
Truck: 55psi front, 80psi rear
A very good chart but that was then and this is now.When the chart was printed everything was new and was expected to see heavy use.Today i wonder how many TT's see the use/need for that much air? I also wonder about the quality of even new 600x20 we have today.Under inflation and the overheating it brings will wreck the best tires in a hurry but on a TT?? Bud in cold Wheeler,Mi.
I agree with Bud. That's why I run mine at 50-55.
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 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, 45-50 pounds instead of 55-60 pounds, for the front passengers, the car will ride much more smoothly (I've had extensive surgery on my spine, so I really do need to smooth out the bumps). -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.
One TT rear tire. Made in Ohio.
Steve,That said Rib type as in a ag implement? If so the 6 ply rating would be different from a on road truck tire 600x20.When i worked at Olds we had skilled trades people from a closed Goodyear.At the time was told ag imp tires were built from scrap rubber from other tires. In the early 80's when Olds was going great guns we had trades people from all over the country.Now thanks to on and on we have empty large pieces of land and old farts like me sitting at the mall wondering what happened?? Bud.
Thanks all. I'll start at 55psi for front and 60psi for rear and she how it runs, then adjust if required.
As a last follow up. Talked to Lucas Tire today, which is where I bought the tires. They confirmed 60 psi for the front clinchers, but advised 35 psi for the rear 600 x20 tires, with a maximum of 40 psi.
600x20 so far 35-80 lbs. ???
From Coker web page. just for fun.
SKU: 75580GTIN UPC: 00842199101638Product Size: 600-20Rim Diameter: 20Tread Width: 4.25Section Width (Actual): 6.00Overall Diameter: 32.25Max Load Capacity: 1350@36PSIRecommended Rim Width: 3.00Tube Type or Tubeless: Tube
I have same Denman on my tt that Steve posted. They are relatively new and sold through t vendors if I recall. Agreed to different pressures by different manufacturers. I have to admit I am not hauling heavy loads or high speeds so I don't worry much if at low pressure range stated on tire. What is the brand Thomas? Am guessing US royal?