TrailManor Owner's Forum - View Single Post

**rickst29** · 12-08-2008, 11:58 AM

except for the "clamping required, no initial tack" problem, this stuff is great.

- - - - -

I have an idea, for such "rough" trips, however: When a friend and I take our SUVs out for some off-road "bouldering" fun, we always drop the PSI in the tires by several pounds: more grip, and more flex reducing stress on higher-up suspension components. We're often letting air out of our "35-40 PSI" SUV tires, taking them all the way down to the 15-20 PSI range. Very effective, but you CAN'T drive fast on such under-inflated tires, and need to re-inflate them after playing around.

The same thing probably applies to TrailManor, although to a somewhat less extreme degree: Since you're not going even 25 MPH on such roads, you don't need "stiff" tread to avoid the big, stressful "bubble" which occurs in the tread at high speeds, (at the leading edge of pavement contact, where it's being slammed into the ground at an angle).

If you've got a TPM, like I do, then maybe take off another 5 PSI or so, after tuning to the Goodyear chart value for your axle weight. In my nonstandard 2619, that's getting down to around 35 PSI (because I've got the "big" 3124 tires). Way, WAY below the lazy TM brochure recommendation of 65 PSI. The same would apply to the standard tires, I think, although the chart for your 14" might be be quite different. If the Kumho's allow up to 65 PSI, and Kumho has no such tire loading versus PSI adjustment tables, it might be appropriate make your initial guess from the Goodyear table for MY tires. If they max out at 50 PSI, though, I'd make my first guess from the Goodyear chart for the standard Marathon 14" tires. The Kumhos provide a little bit more sidewall/tread strength, so the Goodyear chart should be an UNDER-estimate of how much air to take out.

What do you think?

12-08-2008, 11:58 AM	#7
rickst29 yes, they hunt lions. Join Date: Aug 2005 Location: Reno, NV Posts: 1,322	thanks for advising of your success.... except for the "clamping required, no initial tack" problem, this stuff is great. - - - - - I have an idea, for such "rough" trips, however: When a friend and I take our SUVs out for some off-road "bouldering" fun, we always drop the PSI in the tires by several pounds: more grip, and more flex reducing stress on higher-up suspension components. We're often letting air out of our "35-40 PSI" SUV tires, taking them all the way down to the 15-20 PSI range. Very effective, but you CAN'T drive fast on such under-inflated tires, and need to re-inflate them after playing around. The same thing probably applies to TrailManor, although to a somewhat less extreme degree: Since you're not going even 25 MPH on such roads, you don't need "stiff" tread to avoid the big, stressful "bubble" which occurs in the tread at high speeds, (at the leading edge of pavement contact, where it's being slammed into the ground at an angle). If you've got a TPM, like I do, then maybe take off another 5 PSI or so, after tuning to the Goodyear chart value for your axle weight. In my nonstandard 2619, that's getting down to around 35 PSI (because I've got the "big" 3124 tires). Way, WAY below the lazy TM brochure recommendation of 65 PSI. The same would apply to the standard tires, I think, although the chart for your 14" might be be quite different. If the Kumho's allow up to 65 PSI, and Kumho has no such tire loading versus PSI adjustment tables, it might be appropriate make your initial guess from the Goodyear table for MY tires. If they max out at 50 PSI, though, I'd make my first guess from the Goodyear chart for the standard Marathon 14" tires. The Kumhos provide a little bit more sidewall/tread strength, so the Goodyear chart should be an UNDER-estimate of how much air to take out. What do you think? __________________ TM='06 2619 w/5K axle, 15" Maxxis "E" tires. Plumbing protector. 630 watts solar. 450AH LiFePO4 batteries, 3500 watt inverter. CR-1110 E-F/S fridge (compressor). TV = 2007 4runner sport, with a 36 volt "power boost".