A-arm lift vs Spindle Lift

[SaltLifeCC]

yellj, a bigger tire means the cart travels further in 1 revolution than a smaller tire. While increased friction may cause getting going to take a fraction of time longer, the overall result is you cover more ground in the same number of revolutions, hence more mph. This is the same principal that causes speedometers to give false readings if using a smaller or larger tire than the speedometer was calibrated for.

[TahoeDawgZ71]

Originally Posted by SaltLifeCC

yellj, a bigger tire means the cart travels further in 1 revolution than a smaller tire. While increased friction may cause getting going to take a fraction of time longer, the overall result is you cover more ground in the same number of revolutions, hence more mph. This is the same principal that causes speedometers to give false readings if using a smaller or larger tire than the speedometer was calibrated for.

Finally, somebody else who understands gear ratios!

[yellj]

I understand gear ratios, in fact, went through this with my Jeep, had to regear differentials to regain use of my upper gears and put in in a different speedo gear to get speedo calibrated, but my Jeep is definitely not faster with 35s over 31s. The geometry makes sense with the larger tire covering more ground, it's the energy side I don't quite get

[SaltLifeCC]

It's all assuming you have enough energy to make the same number of max revolutions, no matter which tires are installed. Or, at least enough to more than make up for the difference in tire diameters. In the case of your Jeep, there is probably enough going on that keeps you from making the same max revolutions as you could with smaller tires, so it cancels out or even overcomes the increased amount of ground covered per revolution.

Scientific formulas aside, there are plenty of us that used gps to clock our carts before and after increasing the tire size to prove that bigger tires increases top end speed. Mine went from about 14.7 to 16.5mph. I'm sure there is a point of diminishing returns you could reach but it is most likely not typical to reach it with carts. Apparently it is possible on a Jeep. :-)

[yellj]

That makes sense, I did the calculations based on 6" increase in diameter and got around 5mph increase with everything else constant, so the real world results you mentioned make sense. Wasn't doubting the results, just like to undrestand. Now I can "justify" my lift even more, we get a faster cart. Thanks for all the responses.

[SaltLifeCC]

I hear ya - we could have just gone with the Joe Dirt response: Why do bigger tires make a cart go faster? "It just does". Haha

Based on your math, we must be losing something in order to get some gain. Because I went up 5" in diameter and gained less than 2mph. Would be interesting to find out what diameter evens things out and then what going beyond that does. But my lift kit certainly wouldn't support that experiment.

[Stevec3201]

I think to make the "bigger tire is faster" theory a reality, requires a more powerfull controller in many configurations. Lets say your cart with an upgraded 500 amp controller will do 25 mph with 18" tires. That controller can still move that cart faster with a better gear ratio (or larger tires). So, if you now replace those tires with 23" ones, you will see the speed increase to say 30 mph +/-

That stock 250 amp controller, just can't get those bigger tires moving much faster than the 18" tires.

[Down South]

Not trying to hijack the thread but: Im putting 22" tires on my on my 07 Precedent "4-12V Batteries" I'm stock except the back seat that I already installed, 6" A-Arm lift that I will install with the tires. Do I need to upgrade my controller and cables? I've heard yes and no.

[Stevec3201]

Originally Posted by Down South

Not trying to hijack the thread but: Im putting 22" tires on my on my 07 Precedent "4-12V Batteries" I'm stock except the back seat that I already installed, 6" A-Arm lift that I will install with the tires. Do I need to upgrade my controller and cables? I've heard yes and no.

You don't have to do anything If you want more torque or speed or both, than you need to decide what you want and go from there. Want torque? New controller 400, 500 amps, AWG 4 Cables (min), HD soleinoid will do. Want speed? New motor, lots of options there. Want both? Controller, cables, HP soleinoid and motor. To do it right will cost you around 1100-1300 $$$ for everything I mentioned. You should talk to scottyb

[Down South]

Originally Posted by Stevec3201

You don't have to do anything If you want more torque or speed or both, than you need to decide what you want and go from there. Want torque? New controller 400, 500 amps, AWG 4 Cables (min), HD soleinoid will do. Want speed? New motor, lots of options there. Want both? Controller, cables, HP soleinoid and motor. To do it right will cost you around 1100-1300 $$$ for everything I mentioned. You should talk to scottyb

Thanks for the reply. The cables, I can do myself since I have the wire, terminals and heat shrink in my shop. The controller would be the expense. I don’t need to go 30 mph. Just torque would do well for me.