im lookin 4 a new tire and was interested in the kenda k772 on rocky mountain m/c but it says it was made for blue groove terrain. wat the hell is that

 

I have a K772 on the back, its heaps better than the stock 603 esp in mud the old 603 would just fill up and drop you on ya bum. The 772 grips and hooks up esp under power. I have no idea what blue groove terrain is.

 

Blue groove terrain, don't know. The blue groove in flattrack circles is the part of the track where the line is through the corners. The tires leave rubber on the hardpacked dirt and create a 'blue groove' line. That's where you want to stay for max speed and traction through the corner.

Good looking tire, Garry.

 

so will a 120/100/18 fit? the first number { the 120 in this situation } is the amount of tread on the tire, am i right. just tryin to see if a 120/100/18 will fit. thanks. oh yeah, also will a steel sprocket last long at all. i was wanting one of them cause they're so cheap but i dont wanna buy a piece of crap

 

This is covered elsewhere, but I think it goes something like this. If a tire's size is given in the format X/Y-Z, the the variable break down as follows:

X - tire width in millimeters
Y - sidewall height as a percentage of the width
Z - tire inner diameter (or rim diameter that it will fit)

So for the example you gave of 120/100-18, the tire width is 120mm. If you want to talk in terms of inches, then divide that number by 25.4. So the width in inches is 120 divided by 25.4 or 4.72 inches. The sidewall height is 100% of this width, so it is also 4.72 inches, and the tire is made to fit an 18" rim.

BTW, this tire will fit just fine on our bikes. I am running a 130mm wide tire, which works out to 5.10 inches. It fits fine, but I don't think you could go up much if any from there, even if you could find them.

As for the sprocket, I think many of us are running steel sprockets. Aluminum is obviously lighter, but I think they are supposed to wear out much quicker. Someone posted a bad experience with Sunstar rear sprockets, even though I have a Sunstar front that is good. I am running a 45T steel sprocket from JT Sprockets on the back.

Hope thishelps.

 

thanks, i was just makin sure before i ordered. i plan on goin with a steel 48 tooth sprocketin the rear with the 520/110 chain and a kenda 120/100/18 tire. i plan on makin these changes in about a month so the tire will have the knobbies all the way through ridin season and to give my 42 tooth sprocket more wear so i'll have a reason to put the bigger one on ha.