Value of Replacing Load Range B Tires on Older 3-Motorcycle Trailer With Load Range C Tires

Question:

The tires that came with it are 480x12. The max weight is about 785@60lbs. per tire. Load range B. Max inflation is 60 PSI. I was considering getting 480x12 with load range C @ 990 lbs per tire @ 90 PSI. I do not have the trailer in front of me to give you the name of it…but it is an older 3 ramp motorcycle trailer that folds and stands up. It has what I believe a Dexter torsion axel suspension no springs with a dexter hub with that nifty greasing system similar, but better than the Buddy Bearings. My concern is that the increased tire pressure to 90 PSI will cause increased jarring to the torsion suspension, and perhaps send those increased bumps to the motorcycle or motorcycles on the trailer. Should I get the B load range tires as what is on the trailer @ 60 PSI ? Or get the the C load range tires @ 90 PSI. Both size 480x12 and prices are about the same. Thanks...

asked by: Don

Expert Reply:

Replacing your original Load Range B trailer tires on your 3-motorcycle trailer with higher weight- and pressure-rated Load Range C tires will not result in additional stress to your trailer axle or suspension. It is also unlikely to alter the ride quality of the loaded trailer to any degree that would be noticeable.

Generally the various components in a trailer (tires,wheels, hubs, axles) are selected to have common or similar ratings; altering one component in a system will not increase the capacity of that overall system. The only potential benefit to changing from the specified Load Range B tires to Load Range C tires would be some safety margin and perhaps peace of mind if you have concerns about exceeding the capacity of the stock tires. You do not want to exceed the rated capacity of the trailer under any circumstances.

expert reply by: Adam R