'22 350 SXF vs. '24 KX450?

I actually have been leaning back towards the Kawasaki from my 350s which I do love. My good friend has a very lightly ridden 23 KX factory addition he is trying to twist my arm on … i’m a sucker for a good deal. That being said I do have an extra set of WP cone valves set up by REP for Intermediate Vet at 215 pounds I would be very willing to part ways with if you are interested. My weight can fluctuate at times and they have worked well when I was at my heaviest last year at 245. They are in great condition with Marks Spec Cone Valve, National Spring Tubes and bottoming cone. 

“Am I foolish to think the KX450 might be a better option as the more friendly to ride and mellow 450 of the bunch versus putting an ecu and spring forks into the KTM? I figure that would easily kick the shit out 3k or more”

Not foolish at all; I say go with the 24’ Kawi. Not a fan of having to spend money on things like that ECU and spring conversion on your KTM, where just a re-spring will get you so much closer to happiness on the Kawasaki. The 24’ is noticeably smoother and less abrupt than the previous generation KX450 you rode (especially off the bottom), and is one of the best engines for Vet riders everywhere. At your height, the ergos should fit quite nicely too. Kawasaki usually has some good Spring deals, may be a good idea to ask your dealer about the best purchasing timing…Cheers

I have been asking myself this same questions for about 8 weeks now, lol, I have a '23 MC 350 and have considered going to the '24 KX 450. I do have Cone Valves and they are very good but I have ridden a few re-valved air forks recently that are on par with my forks. I also had a Vortex ECU mapped by Twisted on a previous 350 and it is definitely a worthwhile upgrade. (You can also use it on the KX with a remap). I've also ridden the previous gen ('22) KX 450 and I preferred the 350. 

The biggest draw back for me is the weight difference of the bikes. I love the light weight of the 350 because I do like to venture out and do some single track stuff even thought I ride 90% MX. Ultimately, I decided that I am going to wait until I can ride a new '24 KX 450 before I make a decision. I'm in the Northeast so we aren't quite in the swing of things yet with the weather. I'll be following this thread. 

Yeah, there will be enough out there that you ought to be able to take a spin on one and see for yourself.  I’m about the same size as you, and I prefer the extra grunt from the 450 to make up for my mistakes and to help me get to the first corner first (or at least not last).

I’d go with the kawi , I had a 23 350sxf /. 22kawi 450 and here’s the thing … if you go to the extent of ecu and exhaust .. that’s over 2k ..then suspension full kyb swap is I think around 5k….get a 450 throw springs in it set your sag and go personally I wouldn’t worry about a revalve brother that’s a waste of money..cheaper and you got power ..

Anyone with a 24 kx450 wanna swap some laps on a 350 let me know!

I feel like that’s something vital could be used for a bit more is to do some bike swaps amongst non abusive members, for a session or whatever.

would be cool to try some other bikes out and we certainly have the community with all the bikes here.

In the same boat here. That airbox on the KX looks suspect though 

I didn't see anyone on one at Tomahawk last weekend or I would have considered asking them. I did, however, see at least two guys on red 350s haha

I just put down a deposit on the '24 and I'm coming from a 2017 KTM 350. Sounds like the perfect bike for me at 6'2" 210lbs and about to be 40. Loved my 2013 KX450 and this one sounds even better. Really excited to be done with air forks!

The air filter design sucks, but the filter stays cleaner than my 22 KX. The 3D printed filter cage makes replacing the filter much easier. At first I was worried about sucking dirt, but after 5 hours my air boot is super clean. I'm running DT1 filters with some grease around the rim.

I just rode a '22 KX with the softer map coupler. That front end didn't want to wheelie over the first whoop out of a turn. I go 205lbs.. The '24 is prolly like this. '24 has the WIFI map app, for a quick fix perhaps?

I like this idea. 23 350sxf located in SoCal if anyone wants to swap for a few laps. Setup for 210lbs

I recommend going with the newer frame 2023-2024 KTM 350 if that is an option for you. I own a 2023 gas gas mc 350 (older frame) a 2023 KTM 350 (new frame) and a 2024 KX 450. My favorite bike by far is the 2023 KTM 350. I am similar in height and weight to you and the new/ stiffer KTM frame is perfect in my opinion for heavier riders. It's much more precise and not wallowy/flexy at all compared to the older KTM frame and it has a little more bottom end compared to the older KTM 350. The new Kx 450 feels like a slightly slower and heavier 350 in my opinion.  The 2023 Ktm 350 is more exciting off the bottom than the Kx 450 and more stable as well whereas the kx was twitchy in the front end. Also, the overall durability is so much better on the KTM 350. I have already had to replace a clutch on my Kx after 9 hours and my KTM 350 has over 30 hours on it with the stock clutch.

Regarding the suspension, I tried a spring conversion kit and cone valves and I ended up going back to the air forks. The air forks have much better hold-up compared to any spring fork for a rider over 200 pounds. I had ENZO revalve the air fork and shock and the bike has been great. (The air fork revalve is so much cheaper too because you don't have to pay for spings)

In my opinion, the vortex ignition is a waste. it cleaned up the power delivery a little but made the bike very violent and less rideable. I just changed the gearing to a 13/49 which will give you a little more bottom compared to your 14/52 gearing. 

I enjoy my gas gas 350 and ktm 350 much more than the new KX 450.

Edit: Depending on where you are located you can get a new 2024 350 for around 9k otd with the rebates rolling in so you can probably save some money as well

Anyone else with any experience to share? 

I recently purchased a 24 kx450 and came off of a 22 ktm350sxf with spring forks and vortex mapped by twisted w/race gas 
 

So the meat and the potatoes is my kx450 with the gromet removed and a slip on is very comparable to my 350. 
 

that being said I am happy to have that because I will eventually install and remap my vortex and run race gas. That in conjunction with a power flow kit I will be good to go. 
 

I am 250lb vet c rider. Not fast at all just do it for the love of it. 
 

the kx to me has very similar front end feel in the corners but more stability in the straight line. The chassis on the kx is so good in the chop. 
 

just my .02

23 MC350 with the sss fork kit, map switch, and+2 rear sprocket. Honestly I liked my 2021 mc450 better. I'll wear the 350 out, and the next bike will be at this point most likely a Kawasaki 450. Honestly it was my first overpriced bike, and most expensive suspension I've ever had. Hindsight is 20/20, and I probably won't be getting a KTM tramp stamp like a lot of vet riders. 

Great feedback. You did not really say, but are you overall happy with the change? Hoping for more? Any regrets? Anything you feel the the 350 did better or areas you prefer the 450 was more like the 350?

I am very happy with the switch. I have no regrets! 
 

Honestly both bikes are very similar entering the corners to me. 
 

once I added the slip on the bike did get more connected feel to the rear wheel. But prior to that it was still very comparable. 
 

I rode a test bike that had all the mods done to it including a vortex and it was very powerful but still very manageable. 
 

I ride Glen Helen a lot and at times during racing I would be forced into a line that wasn’t favorable to the 350 before a hill. That was one area I wasn’t fond of the 350. But let’s be honest. Anyone that is getting a 350 is most likely buying it to have the capability of riding longer motos without being worked to death. 
 

the kawi is just as equal to the 350 in that department in my opinion. 
 

only con so far is the hardware sucks lol. I can see some timeserts being used in the future 

I have a 23 350sxf and a 24 kx450 with about 20hrs on each. Have kyb forks on 350 but otherwise stock. You really can't go wrong with either of these bike, they are both awesome and I really can't separate them. I will say that anyone who says the kx is comparable to the 350 must be riding it bone stock. With a few simple and free mods the kx450 blows the 350 away in the power department. 

I have ridden 350s since 2016 and they are fun bikes but racing mx I am better off on a 450.

Got a yz450f-24 now.

Rode the kx 450 -24 bone stock last week and it has nice smooth power. Much more bottom than a 350 ofcourse. Very linear power curve and is much less fatigueing than riding a 350.

The yz450f has a very fun and exciting engine.  The kx is more mellow and manageable but still has great power. 

Have ridden both. Own a ‘24 KX450. Prefer the KX.

Neither bike can get away from you easily when fatigued, but I prefer the extra torque of the 450. I can be lazier but still not worry about a loopout larry moment.

win win either way.

Probably doesn’t help but I had a 19 KX450 and if you put the white mapping coupler in it was probably about like riding a 350. Was not abrupt at all. So something to consider you can do with the new one to smooth it out. 

As time goes on I am much more on the kx450 side. I have everything but a vortex, it is real easy to ride and is nice to have that extra power with out getting tired. For some reason I feel so comfy on it and the rider triangle is literally perfect for me. 

I personally have always felt that There is no replacement for displacement. 

250 350 or 450 depends on your personal riding preferences.

Do you like revving it out to find power or do you like torque?

I had a 23 350sx that had a Vortex. Just spun some laps on the a 24 450kx. It had the air box opened, baffle and screens removed from the stock muffler. Chassis was definitely better on the Kawi. As both bikes sit I wouldn’t say the Kawi blows the 350 away power wise. I’m curious, what have you done to yours? 

For bottom end I'd go for the 450. The 350 likes to be revved out as you probably know. Torque curve on a 350 is almost identical to a yz250F there is just more everywhere. I've got the vortex on my 350 and it definitely helps it run cooler and pulls harder but there's no replacement for displacement. 

Yeah blows the 350 away was probably the wrong wording. I'd say it is significantly stronger through the meat of the power and the torque feeling is obviously alot better on the kx. Off the initial crack of the throttle there isn't alot in it, the 350 has very lively quick revving feel compared to the kx. I am comparing a 23 350 though not a 22. I rode my friends 22 husky 350 with a 366 big bore kit yesterday and I'd say my 23 350 is probably stronger than that.

My kx just has opened up airbox and full PC ti6 exhaust. 

I know you said it was between modding your 22 350 or a 24 kx450 but I would highly consider a 23+ 350. They are significantly better off the bottom than the earlier models. With almost 30hrs on each now I am slowly leaning more towards the 350 side. Both bikes are awesome but I just find everything a little easier to do on the 350, and find myself with a bigger smile on my face after a day on the 350 compared to the 450. I just wish the japs would get there shit together and build 350's to give us some more options. 

I would also recommend the new-gen 350. I've had a 2016, 2019, 2022, and 2023 FC 350 and while I've loved them all, the 2023 is the biggest step forward they've made. It's not mandatory to rev the thing to the moon anymore, the bottom end power is markedly improved and you can lug the bike like a 450 now without the fatigue of the extra rotating mass that others have mentioned, or you can still ring the thing out. They really found the sweet spot. In that same time I had a 2021 KX450 and I just did not like riding it as much. I could ride it ok but I always felt like I was just kinda of managing the bike around the track, especially as the track got rougher, and eventually it would wear me out. The 350 has more than enough power and I can actually charge on it and ride a full Moto. 

Just my 2 cents but I think the 350 is an absolute no brainer, whether you do an ECU on your current bike (which from what I hear does make a big difference) or if you update.