Tire choices

[Christ]

Originally Posted by Frank Lee

A golf cart then. Those tires look like trailer tires. Are they?

Actually, I think they're off-road tires, like those you'd find on garden tractors, etc.. I've used those garden tractor tires on low-speed trailers, though, since they're mostly 5x4.5 bolt patterns with big center holes, they'll fit a large number of american car hubs and several Jap hubs too.

I'm not suggesting that we put these things on high speed vehicles, or on trucks that are meant to haul stuff around (even at low speeds), but maybe for a GEM electric car-type thing, it would be a viable option.

I'm still going to use them if I ever get a chance to go to a track and run again, though.

[CapriRacer]

Originally Posted by Frank Lee

A golf cart then. Those tires look like trailer tires. Are they?

Some are, most aren't. Most tires designed for golf carts are designed to be used the way a golf cart is used - intermittant usage for short periods of time on paved surfaces with some usage on solid ground with a large consideration given to a large surface area to avoid damaging the turf. This generally means that the tires on golf carts are unsuitable for street usage - and generally can't legally be used for street usage.

[Huntr]

Originally Posted by CapriRacer

Consider for the moment: A 4.80-12 Load Range C has a load carrying capacity of 785 pounds at 60 psi. A 175/70R13 (a pretty common but pretty small tire) has a load carrying capacity at 1036 # at 35 psi. That's quite a difference.

According to Carlisle Tire (and every tire website I found today looking for 4.80x12 tires), a 4.80x12LRC tire has a capacity of 990 @ 90 PSI. It's the 4.80x12LRB that has the 785 @ 60 PSI. 990 to 1036 is not much of a difference.

[CapriRacer]

Originally Posted by Huntr

According to Carlisle Tire (and every tire website I found today looking for 4.80x12 tires), a 4.80x12LRC tire has a capacity of 990 @ 90 PSI. It's the 4.80x12LRB that has the 785 @ 60 PSI. 990 to 1036 is not much of a difference.

You are correct, but the original post was about 4.80-12 Load Range C's at 60 psi - and in that case the load carrying capacity at 60 psi is indeed the same as the Load Range B - 785#.

There is either have a large difference in load carrying capacity or a large difference in inflation pressure needed for the load.

[bgd73]

if it looks like this, I'd say no way.

its kinda lkike a 10 geared sube at 3000 punds and full lock diffs...with tire size in photo oem. It really can get ridiculous. think safety. economical is as big as the engine and wheels and tranny take with throttle response minimal. It is NEVER correct by factory..going smaller is quite strange to ask.

[Christ]

Originally Posted by bgd73

if it looks like this, I'd say no way.

its kinda lkike a 10 geared sube at 3000 punds and full lock diffs...with tire size in photo oem. It really can get ridiculous. think safety. economical is as big as the engine and wheels and tranny take with throttle response minimal. It is NEVER correct by factory..going smaller is quite strange to ask.

Smaller = less rotating mass to accelerate, but the 4.80/12's are actually pretty close to the same size as 155R13's. You can change gearing on a OEM vehicle to account for tire size changes.

Once again, I was figuring on using something like this on a small vehicle, like an NEV or something similar.

[MechEngVT]

Golf carts are almost universally 4x4" bolt pattern. I think the Austin Mini used that pattern and essentially the same size wheel/tire as golf carts, only a bit narrower.

You can get ultra-lightweight single-pieced forged alloy wheels for racing minis (wheel is IIRC 12" and like <8 lbs) and DOT winter tires from Yokohama and the mounted/balanced wheel and tire are <17 lbs. I know someone who tried this on a golf cart to improve ride on pavement-only operation, and I want to say it was right at $100 per corner for this.

The winter tires were used because they were the only thing (or the only light thing) available in the OD required for a golf cart. Stepping up the OD slightly would probably open a few options, reduce rolling resistance, but slightly increase weight and inertia.