2-Five with Staggered Wheel Set-Up and 225/40/14 Tire Performance Question

[kabinski]

Current tire set-up on my 2019 2-Five is 215/40/12. It took this set-up to achieve the factory top speed (GPS tested) of 25mph. The factory 10-inch set-up only reached about 23mph.

I am contemplating going with a staggered set-up of 14" in the rear and 12" in the front in order to not have to modify the front suspension to clear 14's. Tire wise, I would go with a 225/40/14 rear and stick with the current 205/40/12 front.

Going with the 225/40/14 rear, I realize ride height in the rear will increase a bit over 1" (tire diameter will increase by 2.3"), but I don't think that will pose any problems ride or handling wise. With the larger rear, I should gain about 3mph over my current set-up.

My question is, will this larger rear size affect acceleration much? I know I've seen many 2-Five's with 14's, so I'm assuming it's not too much of a decrease in performance. My previous cart was a 2009 RXV with a speed/performance upgrade that ran approximately 22mph. It had 14's and the acceleration was actually a fair amount quicker than my factory 2-Five. I just don't want to go this route if it's going to dog the performance too much just to gain a few extra MPH's. Although I'd really like to hit that 28mph mark.

Any thoughts or insight would be greatly appreciated. Thanks!

[JohnnieB]

Rim diameter has nothing to do with cart speed or torque or other performance factors. It is tire height and the gear ratio in the differential that effect speed, torque and acceleration.

Stock gears in a 2-Five are 14.76:1.
Stock tires are 205/50-R10 (18" tall).

Your current 215/40-12 tire are 18.8" tall, so you have a 4.4% speed gain over stock and a 4.3% torque loss.

Going to 225/40-14 will up to tire height to 21" tall with a 16.7% speed gain and a 14.3% torque loss (over stock)

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Going from 215/40-12 to 225/40-14 will be a 11.7% relative speed gain with a 10.5% relative torque loss.

If you are getting 25MPH o the 215/40-10 tires, you should (mathematically) get 27.9MPH on the 225/40-14 tires, but the cart probably won't go all the way up to that number due to the torque loss.

[kabinski]

Originally Posted by JohnnieB

Rim diameter has nothing to do with cart speed or torque or other performance factors. It is tire height and the gear ratio in the differential that effect speed, torque and acceleration.

Stock gears in a 2-Five are 14.76:1.
Stock tires are 205/50-R10 (18" tall).

Your current 215/40-12 tire are 18.8" tall, so you have a 4.4% speed gain over stock and a 4.3% torque loss.

Going to 225/40-14 will up to tire height to 21" tall with a 16.7% speed gain and a 14.3% torque loss (over stock)

--------------
Going from 215/40-12 to 225/40-14 will be a 11.7% relative speed gain with a 10.5% relative torque loss.

If you are getting 25MPH o the 215/40-10 tires, you should (mathematically) get 27.9MPH on the 225/40-14 tires, but the cart probably won't go all the way up to that number due to the torque loss.

Wow. I appreciate you taking the time and spelling it out in great detail like that. You just convinced me to stick with what I have. That sounds like more torque loss than I was hoping for.

I'll definitely be searching for other means to achieve my goal for a few additional mph's. I live in North Myrtle Beach, SC, which is a golf cart haven. My wife, son and I often drive on Ocean Blvd which is a 35mph street. A few extra mph's would be nice there.

Any quick suggestions for what I'm seeking (a little extra speed without too much torque loss)? I think I read a while back of someone on here who re-programs the factory controller, or something along those lines. I'm a bit of a wrencher and would love to tackle it myself if the option was available.

Again, I appreciate your time! You saved me $600 in wheels and tires

[ojo]

I think, with reprogramming the controller you can reach the speed limit of Ocean Blvd, but while driving with your family on public roads, you'll have to watch the rear mirror all the time, If the police is behind you

[BobBoyce]

Originally Posted by kabinski

Wow. I appreciate you taking the time and spelling it out in great detail like that. You just convinced me to stick with what I have. That sounds like more torque loss than I was hoping for.

I'll definitely be searching for other means to achieve my goal for a few additional mph's. I live in North Myrtle Beach, SC, which is a golf cart haven. My wife, son and I often drive on Ocean Blvd which is a 35mph street. A few extra mph's would be nice there.

Any quick suggestions for what I'm seeking (a little extra speed without too much torque loss)? I think I read a while back of someone on here who re-programs the factory controller, or something along those lines. I'm a bit of a wrencher and would love to tackle it myself if the option was available.

Again, I appreciate your time! You saved me $600 in wheels and tires

As mentioned, you don't want to increase tire size too much on a 2-Five. The 2-Fives gear ratio is a bit more affected by tire size increases compared to the RXV gear ratios. Loss of torque for hills and top end is an undesired result.

I have reprogrammed 2-Fives and also set them so that Turtle mode can be used to stay compliant with the lower 25 MPH LSV speed limit, and have Rabbit mode for higher speed roads, ie MSV operation.

Bob

[kabinski]

Originally Posted by BobBoyce

As mentioned, you don't want to increase tire size too much on a 2-Five. The 2-Fives gear ratio is a bit more affected by tire size increases compared to the RXV gear ratios. Loss of torque for hills and top end is an undesired result.

I have reprogrammed 2-Fives and also set them so that Turtle mode can be used to stay compliant with the lower 25 MPH LSV speed limit, and have Rabbit mode for higher speed roads, ie MSV operation.

Bob

Thanks, Bob. With one of your reprograms, what top speed might I be able to attain with my current set-up (18.8" 215/40/12's)? Also, in regards to what you stated about not being a good idea to go too large with tires on a 2Five, what are your thoughts on a 21.5" (205/40/14) at the rear? Is even that diameter pushing things too far with a 2Five? If I could achieve 30mph (of course a little more would be a plus) and a little extra torque with my current tire set-up, I'd be pretty satisfied. If going with a 21.5" tire would help and not be detrimental to performance, I'd take that route, as well.

I realize you're on your trip right now (hope all is safe and well ), but would appreciate your thoughts whenever you may get around to responding. Thank you.