what does the 'J' mean?

scullyfu · Post by **scullyfu** » Thu Jun 20, 2013 7:28 pm

looking at purchasing the michelin S1 tires, but came upon a dilemma. when i go to select from the drop down menu for the tire size, 2 of the options that sound correct are:

90/90J-10 AND 3.50J-10

here's the link: http://www.motorcycle-superstore.com/5/ ... toComplete

which one of these should i select for an 09 buddy 125?

thanks in advance.

az_slynch · Post by **az_slynch** » Thu Jun 20, 2013 7:56 pm

The "J" is the recommended speed rating of the tire. In this case, "J" indicates that the maximum recommended operating speed for the tire is 62mph.

Here's a bit more info to help demystify tire codes:

http://en.wikipedia.org/wiki/Tire_code

Either tire will fit a Buddy. the 90 is 90mm, which equates to 3.54 inches. Considering the variations in tire size between manufacturers, both codes are essentially the same size.

scullyfu · Post by **scullyfu** » Thu Jun 20, 2013 8:59 pm

thanks, az. one more question: if the tires are virtually the same, why the price discrepancy? the 90/90j-10 is $25.99/ea; the 3.50j-10 is $34.99/ea. strange.

guess i'll tap into my scottish heritage and go with the lesser of the two prices.

jrstone · Post by **jrstone** » Thu Jun 20, 2013 9:22 pm

Is one of them tubeless and the other not?

Rob · Post by **Rob** » Thu Jun 20, 2013 9:48 pm

The quick reference guide I use for tire ratings:
http://www.webbikeworld.com/Motorcycle- ... e-data.htm

And I'll apologize for some overkill, but a good site for all you ever wanted to know about tires:
http://www.motorcycleanchor.com/motorcy ... tires.html

Rob

scullyfu · Post by **scullyfu** » Thu Jun 20, 2013 9:58 pm

jrstone wrote:Is one of them tubeless and the other not?

it is not indicated as such; just different price range for different sized tires. puzzling, to be sure.

350kmi · Post by **350kmi** » Thu Jun 20, 2013 11:27 pm

According to Michelin's site both sizes are tubeless but can be used with a tube - "TL/TT"

http://www.michelinmotorcycle.com/tires/michelin-s1#dim

In theory (or at least mathematically) 90/90-10 and 3.50-10 should be about the same size, but in my experience 90/90-10 are actually a bit smaller. Both my Vino and Buddy have Conti Zippy 1s, the 90/90-10 on the Vino are about 1" shorter than the 3.50-10 on the Buddy. It was the same with the original Cheng Shin tires that came on both scoots. The widths are about the same. Not sure if the height difference matters too much, I occasionally drag my center stand in sharp corners, so I have stuck with the taller size.