How do you read tire & rim measures? Say for the XRM, specs are 2.50x17, does that mean you have size 2.50 rims and size 17 wheels?

What does the 110/70 stuff mean?

So when you get mags you only specify rim size?

BTW what effect does getting a larger or a smaller wheel size have?

-Antoine

antoine,

2.50X17 means that the diameter of the wheel is 17 inches and the width of the wheel is 2.5 inches.

Obviously, you are restricted to using a 17 inch (diameter size) tire, also the size of the width of the wheel will restricts your choices of tire tread width. Clearance issues with the front forks and rear swingarm will also restrict tire tread width choices.

Going to a larger tire may mean a taller tire (diameter) or wider and taller. Both changes will have to be done considering the wheel size and clearance issues described above.

To be safe, make sure you replace the wheel with the same dimensions as stock or carefully measure the clearances if installing a taller or wider wheel.

110/70 means that the tread of the tire is 110 mm while the aspect ratio is 70% (ratio of the tread width to height of the sidewall 77mm/110mm = 0.7 or 70%)

antoine,

To Know More About Tire & Rim Measurements
Click Here!
http://www.dropbears.com/u/utilities/tyrerim.htm

Hope This Helps! ;)

Hey thanks a lot guys! I noticed most wheels on the net have a front wheel and a rear wheel version. Since the xrm has 2.5s on both, that means that only the front version fits my wheels. Will wearing two "fronts" cause any problems?

And do you think 3.0 mags/rims will fit the rear of the XRM? I was hoping of having a 2.5x17 front and 3.0x17 rear like the aprilia tuomo 50cc. Whaddya think? (Dreaming of 5-spoke alloy rims!)

Oh and what are the considerations for tubeless versus tubed tires?

Agh, these wheels. :)

Tubeless tires are better and safer than tube type tires (blow outs are minimized). Some wheels (some wire wheels) require an interior tube. Some wire wheels (those on some newer BMW do not require tube type tires. Try to use tubeless tires if possible and appropriate for your ride.

Wider tires are installed by manufactures because they are necessary to handle increased power from improved engine performance or sometimes because they want to dress up the bike.

Switching to wide tires however tend to slow down the response of the bike when initiating a turn. Installing a 3 inch rim to fit a wider tire makes the tire wheel package heavier and therefore puts an extra strain on your motor and your suspension (heavier unsprung weight). Clearance issues involving your swingarm should be resolved before trying it out.

I suggest using a same size as stock premium tire first to improve the handling of your tire rather than going wider or bigger. Check out other people's changes and see what works and what doesn't. Good Luck. cdc

Hmmm ... informative thread. :)

My scooter tire's 130/60-13 ..... so it means that it has a tread of 130mm with an aspec ratio of 60% and a diameter of 13 inches.

Em I right CDC?

yes. The diameter of your tire mounted on your rim but not on your scoot should be about 19 inches. This may vary depending on inflation pressures and manufacturer. It is just an estimate for comparison purposes.

IC, thanks again. :)