mo1
Platinum Member
Since we have delved down into the physics of how tires work I would like to ask why the front tires are usually so small? I'm thinking the reason being for steering purposes? If it's a silly question forgive me but I figure lets not leave any stone unturned at this point.
Front tires are smaller in diameter than rear tires in no small part because a smaller diameter tire allows for a sharper turning radius with similar axle width as compared to a larger-diameter tire. As was previously stated, a large tire cannot be turned to as sharp of an angle as a smaller tire with the same axle width as the tire would strike the side of the tractor. You would need to have a much wider front axle in order to push the hub of the inside front tire out far enough so that the tire won't strike the side of the tractor when turning. Look at the difference between a planetary-hub MFWD utility tractor and the same tractor in 2WD form. Axle widths are very similar but the MFWD unit will have front tires about 1/3 larger in diameter than the 2WD tractor to give relatively similar ground clearance under the front axle. The MFWD tractor will have a turning radius that is roughly a third wider as a result.