What is the largest tire can fit on the back of my 06 WR450f

Hey guys, I have almost 1000km on my bike already and the back tire is taking a beating, gonna need to replace it soon, Can I fit a larger, wider and taller tire back there? I was looking and think i have room for maybe one size larger but want to know forsure first if it will fit ok with no rubbing issues. I have a 110/100 x18 on there now, whatever that means, Im use to the old 4.10x18 like my old yammy had, not sure on this new metric sizing.

Good question. I'm going to be doing a lot of riding on the beach and wonder if wider is better like it is with jeep tires in sand. I'm thinking of going with a 120/100x18 as that seems to be the widest that either Maxxis IT or Dunlop 952 come in. Would wider be better for me or should I stick with a 110/100x18?

I think wider would be better too in the soft stuff, i do alot of playing in the sand also....

i picked up a 120 several tires ago...the increased unsprung weight made a noticable difference in the feel of my suspension...i didnt like it..

Was that a 120/100 or a 120/90, All i can seem to find is a 120/90 and im not sure if that means it's higher or wider or lower or narower, can someone explain this sizing to me please?

1st number is the treadwidth in millimeters.

2nd number is the aspect ratio (sidewall height) expressed as a percentage of the treadwidth.

3rd number is the rim size.

So...120/100-18 means, 120mm in treadwidth, the sidewall is 100% of the treadwidth (120mm), 18" rim...SC

The advantage of a higher wall is less punctures on rocky terrain, I fitted a 120/100x18 on my TTR & like ARin didn't like the feel of it.

Thanks for the input. So if you two were going to live on the beach would it change your opinion so that you could have the extra 10mm width or do you think I should stick with the 110mm?

So will a 120/90 or 120/100 fit ok on these bikes?

I use a 140 Michelin s12 no problems with clearance, but couldn't go much wider.

I run a 120/100-18 Maxxis IT exclusively with no issues...SC

Teraflex makes the widest tire available to my knowledge. 150 is the usa version and the 140 is the crap japanese version... Or that might be the other way around, i forgot. I have seen them both on a 99 wr400. Tight but you should be able to run whatever you want, even these babies.

I run a 120/100-18 Maxxis IT exclusively with no issues...SC

Do you like the 120 over the 110? I'm thinking it would be better in sand then the thinner 110.

Do you like the 120 over the 110? I'm thinking it would be better in sand then the thinner 110.

The 120's hook up better with the power of the 450.

The difference is a lot more noticable on the WR250, where the 120 takes a lot of the zing out of the bike. Not good.

Im running a Perelli 130 on my 99 and it hooks up better, feels more secure to me. Have not seen a downside to the bigger tire, and I also sized a 150 and it looked like it would fit too fwiw.


Don't forget differences between European and Jap sizings.

I think a 140 Michelin = 120 Dunlop.

Matty is right michelin sizes and some others are deceiving. I know Maxxis's 120 is a true 120 and I love the tire.

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