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19 inch vs 18 inch rear wheel

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What is the advantage of the 18 inch rear wheel vs the 19 inch?

I recently purchased a tc450 with the 19 but have heard of some riders switching to the 18. The tires seem to be similar in height, just shorter sidewall on the 19. :applause:

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What is the advantage of the 18 inch rear wheel vs the 19 inch?

I recently purchased a tc450 with the 19 but have heard of some riders switching to the 18. The tires seem to be similar in height, just shorter sidewall on the 19. :applause:

If the overall height is the same then the difference is the mass of the tire, less sidewall means less rotating mass which will give a 19 quicker acceleration, effects handling characteristics like cornering, less mass will have less angular momentum making it quicker to change directions in turns and so one, mostly things that you would want on an mx track. Conversely a 18 with more rotating mass will affect these things in the opposite way and give more cushion for the suspension, better for offroad riding. Maybe there is a less techical reason too, but that is the basic physics at work here.

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In addition to the above they resist pinch flats better due to taller sidewalls, tend to conform to trail irregularities better and generally there is a better selection of 18's.

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Most I agree with, but for off road tires, I dont think 18" have that much better selection any longer for off road tires. Dunlop, Michelin, Pirelli, Maxxis all offer Desert tires in both 18 and 19" sizes. Rob Barnum raced the Baja 1000 on his stock 19" rear wheel without flats on his 06 TC 510. We raced our 06 TC 510 with an 18" rear wheel. Both teams used Maxxis Desert ITs.

With that said, we use 18" out of habit. I use 19" as spares, since I have several rims from 18" conversions now. Ride, you driving down for both Husky rides ( 5 day in April and 2 day ride in May) from Washington state or just the weekend ride (2 day ride)?:applause:

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A couple of the brands/models I like are offered in 18 but not 19. I'm guessing these are probably soft terrain tires and you are always looking at hard pack tires. :applause: I know the selection of 19's is less that 18's for soft terrain stuff. While 19s work fine i do prefer 18 off road especially here in the NW as i feel they hook up a lot better in mud and slick stuff. The added plus is they are easier to mount up. Additionally 18 inch verses 19 on the same bike the 18 will add a little flywheel affect as it weighs more. On the down side that's also unsprung weight which your suspension does not like.

As for the 8-13 Baja ride I can make those dates because i have races on or to near that date that I am already signed up for / committed to.

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All good points, especially for terrain you ride up there vs terrain I ride down here. Ride is approx same dates each year. Maybe next year? :applause:

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19 is for track riding where an experianced rider knows how much air he needs to prevent flats & broken wheels for the obsicles of that track and conditions. Light tire make the bike ultra responsive and quick.

18 is for the guy who is blasting into unknow stuff and wants to reduce the risk of flats and bent/broken wheels at some sacrifice of performance

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a 19 quicker acceleration, effects handling characteristics like cornering, less mass will be have less angular momentum making it quicker to change directions in turns and so one, mostly things that you would want on an mx track. Conversely a 18 with more rotating mass will affect these things in the opposite way and give more cushion for the suspension, better for offroad riding. Maybe there is a less techical reason too, but that is the basic physics at work here.

Good answer. Yeah, the opposite being true in that the taller wall of the 18 allows it to flex better for better traction off road. It will provide better grip over off camber rocks and junk. The tire surface area will more easily bend to make contact. It is a noticeable difference - but worth the cost to switch wheels? I don't know. Guess that depends how deep your pockets are.

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the 18 inch is much easier to change ..especially if you run mousses...it hooks up much better than 19 in places where grip is low, especially rocks, and rough terrain..you get a bigger contact patch and the sidewall deformity helps a lot for sure , to bend the tire over stuff.

i am not great on the physics of the whole thing but you get the idea, but for motocross stick with the 19" :applause:

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I ride trails mostly and thought the 18 inch was a must, but I didn't really want to switch just yet.

I think I will leave the 19 incher on for now to try out the ultra responsive handling and quicker acceleration.

Thank you all for the great input. :applause:

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