Question about tire sizes

[Mud_Boggin]

Hello,

My friend is looking to buy some new tires for his 1995 Kawasaki KE100. His front tire stock size is 2.75-19 and his rear is 3.00-17. My question is how do we determine what other types of tires can fit on this? We can't find all too many decent tires with that tire sizing code. I understand the last number is the rim size, but we don't know how to find tires that do not have the decimal number ex. 70/100x17. In that tire size I just said, what size would his stock tires be in that coding?

Thanks, Matt

 

[JST122]

Im not sure if I understand your post but maybe I can help. If you are asking what 70/100X17 means. The first number (70) is the section width of the tire from one side wall to the other, measured at the widest point. The measurement is done in millimeters so in your case the section width would be 70mm. The second number (100) is the tires aspect ratio. The aspect ratio is essentially a measure of the tire's sidewall height. This number is a ratio or percent of the section width so in your case the tire's aspect ratio is 100% of the tires section width or 70mm again. The last number, as you said, is the rim diameter of the tire in inches. So a 70/100X17 is a 70mm wide (sidewall to sidewall), 70mm vertical sidewall height and 17 inch rim bead.

The first numbers you mentioned look to me like the rim size measurements for the bike, I have never seen a tire measurement given like that. 2.75-19 being a 2.75 inch rim width (from left bead to right bead) and a 19 inch diameter, and the 3.00-17 being a 3 inch rim width (from left bead to right bead) and a 17 inch diameter. So basically you would need to find tires that fit a 19 inch front and 17 inch rear diameter wheel and has a section width that will accomodate your rim width at 2.75 and 3.00. The aspect ratio/sidewall height isnt as crucial, you just need to make sure you buy a tire that is for the correct diameter wheel and will accomodate your rim width. If you go to some tire manufacturers websites they often have a chart that will show you what rim widths are approved for the different section widths of different tires. Find a tire type or tread pattern you are interested in and then pull up the specs on that tire.