I have a 2008 500 sportsman, it has F:26x8x12 and R:26x11x12. I can get a great deal on some tires at my local tire store, but they are F:25x8x12 & R:25x10x12. What kind of loss in performance or rideability would i gain or loose with the smaller tires?

 

The 25" are not considered small on a 500,more like 26" is considered big. You will feel a performance "gain" with smaller tires not loss the 500 Scrambler has 22/23" tires for faster acceleration after all.25" may ride a little rougher on 12" rims do to the side wall cushion effect being reduced in hight.

 

well, you would loose a 1/2" of ground clearance, and your speedo would not read correctly, and I personally wouldn't like the 10" rears

IMO I'd pass on that deal,
PS if you don't mind me askin, what type of tires are they, and how much?

 

I agree with the others. Going smaller will come back to haunt you later. Sometimes that little extra bit of clearance & bite can be the difference between making it through a rough spot and cussing like a sailor when you're stuck!

 

I agree as well on the clearence issue, As far as the width goes I feel that it will somewhat depend on the terrain you ride on and style of tire you go with. Example: My stock rear tires were the titan 489's 25x11x12 and my new tires are 25x10x12 mudlites. Now the difference in height nearly no difference, on the other hand the width when air up to 5-7 psi is only 1/4" different but when down around 3 psi the width difference was quite obvious. Not only that, your going to find variances in the different brands and syles out there. Some run smaller than stated some larger and so on.

 

QUESTION!

If an ATV came stock with 25" tires and, lets say you went 28", would the speedo read slower or faster and by how much?

Is there any way to correct it?

 

The speedo would read slower because the larger tires do not rotate as fast. The whole ATV would also go slower because it takes more power to turn 4 28" tires vs 25".

The larger the tire the easier and smoother it is for it to roll over trail obstacles like logs and rocks.

 

My Thundercat used to top out around 135km/hr
Do you have any idea how much slower the speedo would read going from 25" to 28"?
I guess the best way is to get side by side with a buddy with stock tires

 

My guess, if your both doing say 90 km/hr his speedo will read 90 and yours would read in the lower 80s.

If your ATV did 135KM/hr with stock 25" it will be lucky to hit 100 now with 28s.

 

i dont agree. not to start a flame war but if you have a bigger tire it would roll over more ground with one revolution versus a smaller tire. yes the speedo would read slower than the actual speed but the quad would have a significant speed increase. the only reason that it would go slower is because there is not enough motor to spin the heavier tires.