Bigger Vet Dudes On '21+ KX250's?

I’m 6’1”. 240 ish. +40 +45 A. Currently riding. Racing a 22 YZ250F. Cylinder Works 270 BB. GYTR head and cams. Full FMF. VP U4.4.

I felt the stock 250s just didn’t have enough mid for my big ass. I had a 22 CRF250R and sold it to get the Yamaha. Yamaha had more aftermarket available. Especially with the gytr line. If you have any speed. Skill you will want more than stock. You can be competitive on one if your racing. Just got to ride it harder. Be more aggressive. I’ve Been riding. Racing 450s. Got hurt pretty bad last year. Just wanted something easier. More fun to ride. Love my BB. It’s as good as my KTM350. Handles. Feels like a 250 just has more tq and hp. Enough tq to get me over everything I want to jump. Corners amazing. Typical Yamaha. Great suspension. Most will ask why not just get a KTM. I’m just not a fan of them and I have zero dealer support near me.

Not sure if there is a BB available for the 21. 22 Kaw 250 yet or not. I would look into that before getting one. I believe you would be perfectly happy with a BB 250. Maybe get away with a stock 250 for a little while. HUGE difference between a stock 250 and mine. I have several friends that have ridden it and said they would switch from their 450 to it. It’s just not cheap to build.

Just get an Austrian 450. Weighs the same and will actually pull you.

Gear it how you want it and ride it in low rpm’s and you’ll save more energy than over working a 250.

I am 6ft 195lbs on a 21 KX250. I have a Twisted Vortex, PC full system, PC HC piston and it rips. Oh and I have the PC air boot as well. I can jump everything on it that I can on a 450. More fun ride, easier to ride, and can ride longer on a 250f. I don’t think you will be disappointed

Are you racing or just riding practice tracks? A few years ago I tried racing the vet classes on a 250f with and without a BB kit. I was at the time 6' 175lbs, and would get yarded by WAY bigger guys than me on 450's exiting corners. I would run all over them on corner entry, but forget about the exit. Fast forward a few years and a few more pounds(195# now), I couldn't even begin to imagine riding a 250f at this weight and being competitive, nothing personal but at 250lbs. no way, I don't even think just practicing would be fun on a 250f. Get a 22 YZ450f, ad fuel and retard the timing using the app and it will make it easier to ride for you. You will save money and get a more reliable bike in the process.

6’2 275 B rider, can jump anything and corners are fine if you’re not lazy. Can go as fast as my 450 with effort, rode a 21 and liked it enough to get a 23

I'm 34yo 200lbs and have a 21 kx250. I would say it depends on your speed. Are you already needing more from a 250? If so you probably do need a 350 or 450. I'm a slower guy and I shift into 4th constantly on the 250. You'll also have to shift this bike quite a bit more then a 450 to get the power you want from it. I used to have an 05 rmz450 and I can ride the 250 noticeably longer and it feels much more nimble to me.

Get a 450- I recently downsized to a 350 and am missing the low end torque of the 450. I am 215 without gear.,

Get a kx450 and use the mellow mapping. A heavily modded 250f would be more expensive and less reliable. Unless you plan on racing a 250 cc class

I had a 2015 kx250, loved that bike so fun to ride. BUT when I started racing again +40 a/b I would get yarded on the starts, make it up in the corners and rough parts of the track but pulled again on the straights and hills. Im 170 pounds with gear. Did the 270, and it was an improvement but ran hotter than I liked. Eventually got a 450, but if I wasn’t racing would have stayed with the 250. If your not serious about racing, the 250 is fun and will give you confidence, best thing you can do is get your skills up before getting a 450.

Have you ridden the '23 yet? I am curious if the added power or gearing changes are noticeable?

What class do you race and what’s your riding style? A 250 is awesome if you enjoy being forced to carry more corner speed and momentum. It makes you ride better and it’s very rewarding, and forces you to stay sharp. Most small bores I’ve ridden and raced handle great when you are “over-riding” the bike while a 450 obviously needs to be ridden more politely.

If you already have excellent corner speed, or just don’t enjoy having to ride the bike harder to make up for having less power, you’re probably just going to find it slow.

I always enjoyed riding/racing 144’s and 250f’s and at my lightest I was 6’7 and 250lbs. My race results were the same on the smaller bikes but I rode better and had more fun, I was a C class rider that barely made it to B though.

I haven’t but the guy who got the one before me is super impressed with it. I’m hurt I only got it to make sure I don’t get caught without one in a month or so when I can ride. Lots of dealers getting a bike or two then not getting more for months

6’3 and about 205lbs and I love my 2020 KX250F. Ride that thing on the pipe, revving it out, so much fun. Doesn’t wear me out like my 450 did either

I would just go 350f? Every bike I ever big bored the motor would wear out twice as quick even trying different big bore manufactures. Usually when you add compession and torque to the motor, your main crank bearing will be the first thing to fail or lock up while your riding in my experience which can be scary depending where it happens on the track. Think safety too when you mod a motor.

Im curious if any of you would go up on displacement for tracks at altitude? I mostly ride at 5500’ or higher—potentially much higher (ledvill mx is 10k’).

240ish guy here.

I rode a 22 KX250F and 21 YZ250F back to back in the spring and I liked them enough to buy a mint '21 YZ250F. I did end up selling it after a couple of rides because I wanted to stick with my trusty KTM 350 SXF.

250s are plenty of power, I struggled in deeper conditions but on a hard pack track or late afternoon when the track is baked I really enjoyed riding the 250. You do have to ride it hard. Ultimately I stuck with the 350 because I just enjoy riding that bike no matter what the conditions are. I just got a '23 350 and it's pretty sweet.

At the end of the day is a 250 keeping you from jumping stuff that you would normally jump? Probably not?