18 vz 19 rims

has anyone here ever had a bike that has a 19 rear and switched over to a 18 rim?

would you do it again?

I've ran both offroad....I can't say that I really noticed a huge difference? Word is that the 18 provides a taller sidewall which makes the tire more compliant increasing traction...you can also run a lower PSI. If you plan on running a trials tire you'll need an 18.

yes and yes ! if your running a mx bike off road or trail riding an 18 rear is the way to go.

just bought a excel 18" rim/spoke kit. used oem hub.

had it bujlt in maybe an hour. very easy imo. thought it would be tougher than a bicycle wheel... not even close. think it cost me around 175.

havn't tried it yet since its 3* outside but i'm ready.

can't speak to the accuracy of it, but I recall hearing that the 19 tires have a lower side wall, and as a result are more stable, less likely to come off the rim, in case of needing to ride on a flat.....anyone know?

Edited by doc8m
can't spell/can't type
can't speak to the accuracy of it, but I recall hearing that the 19 tires have a lower side wall, and as a result are more stable, less likely to come off the rim, in case of needing to ride on a flat.....anyone know?

Lower sidewall, more stable for cornering on a MX track.

Bead lock(s) keeps it on the rim when flat.

The higher sidewall of a 100 series 18" tire will help prevent pinch flats.

Plus trials tires only come in 18".

has anyone here ever had a bike that has a 19 rear and switched over to a 18 rim?

would you do it again?

Put a search on this. There is a lot on this. For me it is a huge difference and much better. I not only got an 18 but got a wider rim too. It is smoother and hooks up better. It brakes better too. I ride offroad and don't care about stiffer sidewalls for cornering . The 18's sidewalls are stiff enough. It made a big improvement pm my cr 250 honda. I even put a 20" in the front to go with the 18". I like it and will not go back.:ride:

I even put a 20" in the front to go with the 18"

That's curious. 18" and 19" rear tires generally have the same overall height, just a difference in the sidewall height. Is this the same case for the 20 and 21" front tires? Otherwise you'd have thrown off the bikes geometry going with the 20" front tire. Excuse my ignorance, never seen anyone actually switch to a 20" front.

That's curious. 18" and 19" rear tires generally have the same overall height, just a difference in the sidewall height. Is this the same case for the 20 and 21" front tires? Otherwise you'd have thrown off the bikes geometry going with the 20" front tire. Excuse my ignorance, never seen anyone actually switch to a 20" front.

For the 20" front it is an older option that came with some bikes. My 01 cr 250 had it as an option and the last bike I heard that came with the option was the 07 kxf 250. Guys liked it in offroad as a mod too as it is smoother up front, has better braking and turns better. The front end sticks in turns. Business wise it didn't turn the corner since bikes didn't continue coming with 20's from the factory so It didn't make enough money for most of the major companies to continue making them. There are a few companies making them and that's enough for those that want to keep using them like me. A larger 90/100-21 tire also was developed. I have a 90/100-20 and that works even better for trail. It is nice and smooth. The negative is that it is supposed to climb out of ruts more than the 21" front and it is a bit bouncier in the whoops. Both of those complaints are minor to me in comparison to the benefits. I saw a bunch of local vet riders using them and asked around until I just tried it for myself to see how it was. It isn't a necessity by no means but it makes enough of a difference to me. I had a bad front wheel bearing and used my 21" while I was redoing the 20" hub bearing. At first I thought the 21 was good enough but when I put the 20" back on I liked it much more.:ride: The other thing is the front 20" is also wider I think the difference is 1.60 for the 21 and 1.85 for the 20". I have a wider 2.50 for the 18" (stock 18" 2.15?) on my cr. It hooks up great and is smoother riding. It allows for a larger footprint so it works great for these slippery mud and roots we have here. So far the Pirelli MT16 works best for the back. I am still trying different 20"s up front . I think I have a mt22 up front now and I used an off brand AMS 215 intermediate tire that was only $55 from partsunlimited first . That worked surprisingly good. I'll probably go back to it but have some dunlop 756's to try too . The size and the width of the tire seem to make a big difference. ...oh yea and the overall height is almost the same depending on the brand of 20". The 20 is a tiny bit smaller.

Edited by hawaiidirtrider

19inch- less "give". slightly better traction on motocross track. shorter side wall (more likely to get flats in the woods)

18inch- more "give". slightly better traction in the woods. Taller sidewall (less likely to get flats in the woods)

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now