Front tire ?

80/100-21 or 90/100-21...


I have always used the 80/100/21. Does the 90/100-21 make a noticeable difference? If so, what does it do? I know it is a slightly wider tire. Can you really feel a difference? 

The 80/100 is taller, giving you more squish in the sidewall before pinch flatting.  They usually are lighter, softer sidewalls:  It's great in the dirt.  I run a 90/90-21 on my dual sport, it transitions smoothly on pavement into corners due to it's roundness, and sits a little lower on heavier stiffer sidewalls.  Both your bikes are motocrossers, I think you'd prefer the standard dirt tire, 80/100 but tires are all temporary, wearing out sooo quickly.  If you aren't racing with a season trophy on the line you should try a different tire to see if you prefer it.  You might find your front ends hooks up better?  Rider technique varies a lot and the best thing is for you to see which works best for you, your bike, your terrain / soil conditions.

Edited by motoinmoab

Cool thanks... exactly what I wanted to know. I'm not going to change. I just always wondered what the differences were. I know I don't like the 120 rear like I do the 110 because it is harder to keep the rear end in the ruts. It makes the bike want to climb out of the rut.

I am fairly sure the 90/100 is a wider tire.  Which means a larger foot print and would perform better on dry hard pack surfaces.  

Yes it is... I thought that is what moto meant but after reading his post again it seems that he is saying it is taller.

As with the rear tire thread. The numbers are width/ aspect ratio/ radius. So the 90/100 is both taller and wider. It is 90mm wide x 90mm tall (100% of 90 is 90). The 80/100 is 80mm wide and 80mm tall. So it's narrower and shorter by 10mm in both directions.

The 90 works well on hard park, more bite with the wider contact patch. The 80 works better in softer/prepped dirt, it digs and plants better. The 90 has a tendency to climb out of the ruts in the corners too. This is all my opinion.

Thanks... exactly the info I was looking for.

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