Tire size and speedometer

[TTO5]

To all you guys running the 285 70 16 tires in place of factory 275 70 16 (2000 cruiser in my case) how far off is your speedometer? Any downsides to running the larger tire such as reduced acceleration or any rubbing on body parts?

 

[stinkyfj60]

I think you mean 285/75R16s... That would be a slightly taller tire (and a way more common size) than a 70-series. On my 2000, I ran this size tire with no lift and I didn't have any rubbing problems even when wheeling.

My speedo is off about 5mph or so... it reads under.

 

[TTO5]

Yes I meant 285/75/r16. Thanks

 

[drmwvr]

I have the larger tires and I have run mine with a gps to confirm actual mph. The rule of thumb metric I use based on this info is to add 10% to my speedometer's mph to calculate "actual" speed. This seems keeps me out of trouble!

 

[TXLX100]

There are some websites you can calculate the actual percent difference. There are also several "speedometer" apps available for smart phones that are pretty accurate.