Yes.

 

^^^^^^
Finally something I can use from this thread lol

 

I understand we are talking tire widths here, 100/110/120/130 etc. But the profile ratio matters too doesn't it? a 110/100/18 is going to be about 16 mm taller than the 120/80/18, and a taller tire creates lower acceleration in itself, who knows if its more or less than the 10mm wider tire. Somebody should go out and buy like 15 tires and test it out

 

Time for someone to apply for a research grant.

 

Actually was oriented toward the dual sport tires over the 17s originally - I think.

The point really is to look at the manufacturer's site and see what the tire measurements really are.

I have been looking at Duro. On their site I learned the 120/80 and the 4.60 are virtually identical in every measurable value listed. They are both 4.8" wide, 25.9" tall and 595 lb capacity. The 4.10 is 4" wide, 25.3 tall, and 535 lb capacity. The 120/80 and 4.60 weigh in at 12.3 lb, the 4.10 is 9.9 lb. so I cut almost 2.5 lb of rotating/unsprung weight and can compensate for the smaller diameter with sprockets. Knowing that reduction in unsprung and rotating weight is good as long as traction is adequate, I made a choice from what I learned to try out the smaller tire.

So you see, looking at actual tire specs tell a lot of useful material. I have sites for Bridgestone, Dunlop, IRC, Duro, Shinko, and I think Metzler and Pirelli. I did a lot of research on street tires when I got tires for the Zephyr and also thinking about the SM tires for the KLX650. Really helps a lot to know what is there.

 

If all you gained from this thread is a video of some guy with more money than brains or a really good sense of adventure with low sense of self preservation, you really didn't read anything.

Maybe this will add to what you learn - motorcycle tire manufacturers actually list specifications about their tires, including actual dimensions and recommended rim width requirements. I guarantee you if you do any goofing around with tires it is of great value to know this stuff. Much better than shooting in the dark and having self fulfilling prophesies.

I hope that adds something of more value than a simple, but entertaining video.

 

Well, this thread has changer directions.

“Just a warning in advance:
If you install a 130/90, be prepared for a decrease in performance. That tire is too big for optimum performance on a 250.”

I noticed an increase in performance with the install of the 130-90, not optimum yet, but better than with the original size. My definition of performance is most probably different than someone who thinks the klx 250 is a motocross bike.

“The extra width is a disadvantage when run off road will bog down the smaller engine, when it really needs to spin easier.”

I like traction. When my tire starts to “spin up easily” I consider it worn out and I replace it.

“The only way they work well is if the bike is geared extremely low.”

My gearing is 15/45, that works fine for me.

Pro:
· Big fat tire look. Who cares?
· Profiling image. Who cares?
· It fits the rim. Yes. According to dunlop 3.0X18 is specified as recommended.
· Taller tire may add some top speed if the engine can pull it. Top speed? It’s a KLX 250, there is no “top speed“ low and medium, fast medium on a good day going down hill.
Con:
· Heavier tire. Who cares? Not much heavier.
· Increased rotating mass takes more horsepower to run. “takes more horsepower to run” seriously, what does that mean?
· Increased width a disadvantage in dirt where a small engine needs to break a tire loose when needed. I like traction
· Higher cost for less performance. Bigger tires last longer, they have a higher price but cost is less. Yes there is a difference between cost and price.
“Besides, honestly I don't care what tire you run.” I think you do.

To sum it up:
I used to be that motorcyclists were apt to try things for fun. Like modifying engines and sspensions etc. It seems there are “rules” now.
Death of the adventurer.

 

Taller tire doesn't increase top speed. A taller tire acts like a smaller front sprocket, more rpm at any given speed, but because it's taller you get worse acceleration. Yucky....

 

Taller tire acts like a bigger front, or smaller rear, sprocket I think.

 

15/45 is the same ratio as the stock 14/42 setup, which means you've gained weight (bigger sprockets and longer chain).