KTM 300sx vs 350sxf

300 revs to 9k 350 revs to 13k I really doubt the 300 is faster overall🤷‍♂️

I think those reviews are coming from four stroke riders not used to how quick a 300 lights up. When I hopped on my friends 350 I was at a track that has a big table with a flat 90 before it and a berm on the outside. It’s the type of jump corner combo where it’s easy to clear when railing the berm and takes a seat bounce and everything your bike has to clear from the inside and 250f’s can’t make from the inside. My 300 and his 350 required the exact same amount of corner speed and effort to clear it. IMO they are as close to a match power wise as a two and four stroke can be.  

I think the 350 & 300 make very close HP & torque numbers, just get there a different way. When there is plentiful traction the 300 is quicker, when the track starts drying out and traction is going away the scales tip to the 350”s ability to stay hooked up. Both are great bikes that a capable rider can go very fast on. 

All the 300 needs is a pipe and silencer to increase the overrev, and a two stroke pipe snd silencer is cheap compared to the same four stroke parts. 

I agree, I see tons of people just talking about HP numbers but I would bet $10 that the 350 would smoke that 300 on a track. 300's just don't rev out very well, going to be shifting that thing twice as much.

You can lug a 300 like a 450.

A 125 and 250f rev higher than a 300, you think those are faster too? I rode both bikes again today and like I said prior they are close in overall power but the 300 definitely has the edge on the 350. I have two uphill sections on my track outta tight corners, the 350 is faster than the 300 up those if you stay in second as it revs out further. However the 300 can pull 3rd and the 350 couldn’t so overall I was able to go faster on it there. Being that it can grab a higher gear sooner, the lack of overrev compared to the 350 doesn’t matter. As long as you know how to utilize the 300  imo you can turn better lap times on it compared to a 350. 

Can you get pretty good over rev from just a tune? Or would the port timing need to be changed?

I can jump things on my 300 I couldn’t on my 350. The 300 just makes power much quicker, you don’t need to wait until you have got the motor to 12k 

 If you ride both bikes below 9k rpm the 300 is going to be faster. From 10.5k rpm to 13k rpm the 350 out pulls the 300. I think the dyno is showing the 2022 350 and not the 2023. This is from Vital's youtube.

There isn't a spot on the dyno the 350 can hold a candle to the 300. Not one. 300 makes ~3.5-4hp more everywhere. 10-15% more power through the entire curve. Nobody is riding a 300 2t at 10k rpm.

You do see how the 350 smokes the 300 past 9k rpm right? The 350 has a 2500 rpm range where it makes more power than the peak of the 300 which the 300 only hits for a few rpm. 

It also takes the 350 a lot longer to get there as well. So to maximize the 350's higher hp peak you have to ride it pinned out like a 125 a lot more. More clutch work and not letting the rpms drop off as much. So unless your up around 10.5k often. That advantage drops off. 

300SX peaking at 44.5hp? At 5,000rpm the 300sx is also down 3-4hp(20%-25%), these are 2005’s on dyno, I know isn’t apples to apples but ouch 

The TBI’s being soft on the bottom is on every dyno run I’ve seen.  

That dyno also says the 2005 250f’s make more power or equal power to the 350. It’s obvious those two images do not represent real life.

@wrc787 you pointed out the 350 makes more power than the 300 peak for 2500 rpm, The advantage of the 350 is that long power and its less shifts. I rode my track in 2-3 on the 350 and need 2-4 on the 300. Of those gears the 350 needed 3rd on 3 sections of track where the 300 needed it on 5 sections of track. The advantage of the 300 is I can achieve a higher speed on those straights, I just have to shift more. I ride 2x a week and go to the gym often, so I enjoy the extra speed, extra shifts and excitement of the two stroke a bit more. But I also thought it was fun as hell to ring the neck on that 350. I honestly wanna buy both, and a 125, 450 and woods bike of an undetermined displacement….fucking bikes are fun!

Vital has done this comparison and thrown the 450 in as well

https://youtu.be/qtiQB09bqZc

Let’s compare rpm spread above 40hp for example.

the 350 makes over 40hp for a 4500rpm spread. From 8800-13.4k

the 300 makes over 40hp for a 1500rpm spread. From 7800- 9300rpm as it drops off a cliff.

the 350 makes more peak, makes over 30hp or over 40hp or over 50hp whichever number you’d like to compare for a massive longer rpm spread, but yeah sure the 300s faster?

I find it surprising that a 350 4 stroke needs to be ridden ringing the piss out of it like a 125 compared to a 300 2 stroke. 

If you u haven’t ridden a 350 or a 300 and you’re arguing dyno graphs……just stop. You’re making yourself look like the trailer for Fast XI. 
I own both (23’s) and they’re both fast in their own right. The 350 is my moto bike and the 300 (XC) is my woods bike. The 350 feels a lot more revvier for moto. I’m in central Florida where most of our tracks are deep sand. I can carry a lot of momentum between jumps with out having to shift. The 300 is way more luggier in the woods and less prone to flaming out. The 300 runs out quick on top too which requires a lot of shifting when moto-ing. I am not saying it’s slower, it just doesn’t rev as high. However, the transmission makes up a lot for the lack of overrev. In the pastures, you just grab another gear and she keeps pulling. From the seat, the 300 is faster, no question. It’s almost as if the power is 3k rpm’s lower making it more usable. I’ve yarded 350’s and 450’s in our local hare scramble series in the pasture sections like it was nothing. All of this was done in the white map, stock bike. The biggest difference between the two is the 300 feels like it’s 50 pounds lighter in the woods and I can ride it a lot longer. 
The bikes handle completely different too. Not sure if I mentioned it but the 300 feels 50 pounds lighter than the 350. In wet, greasy swamp land, the 300 is way more controllable where the 350 tends to shovel and push a lot. It’s also way easier to change direction on the 300 than it is on the 350. 
Like I said, they’re both fast in their own right but each one is a tool. These tools do different things so if your job is the same for both, the tool could be the wrong one. 
 

edit: My premod yz250 (2002) doesn’t hold a candle to either one of these bikes. They aren’t even in the same league of power and motor refinement. 

This is why the 350 is easier to ride than the 300. The 300 hits harder in the midrange then signs off quicker, so you shift more. The 300 appeals to guys that want to ride a 2T, everything happens quicker, more intense. Curious…. Have you ridden a 300SX? 

For sure the 350 engine is easier to ride and very mellow compared to a 300. The 300 handles much better, and feels 20lbs lighter. But if you haven’t spent much time on both you might not want to believe the 300 is faster. Some of us on here have and I’m pretty sure we agree the 300 is faster. But nothing revs like a 350, best thing about that bike is the over rev and ability to not ever have to shift up. Both great bikes but I sold my 350 and only ride my 300 these days, it’s just way more fun for me.

What I really like about racing a 300 in the woods (really any two stroke other than a 125) is you can lug 3rd gear in tighter stuff and as soon as you hit an open spot you can blow past people before the next corner.  A four stroke won’t do that unless you are running down a gear. If you make that pass in a more open area, the four stroke will keep pulling while the 300 will have to keep shifting. That is probably why you see more four strokes in gncc. It is more open like mx.

What I don’t like about two strokes in the woods is when you get to a slick hill with a tight turn before it and short run up or a hill with people down all over it is the 4 stroke you can be kind of stupid with the throttle and it just goes up so you can pick your way up the hill. The 2t you have to keep it off the pipe and/or use a lot of clutch to maintain traction. There is also a benefit to that 4 stroke momentum in that the rear wheel doesn’t get kicked around as much and just drives forward. 

A lot of my pasture passes were coming into the pasture where the bike pipes up and gets rowdy quick or leaving the pasture into woods where I could hold it on longer and change direction quick.
Agreed on the draw back of the two stroke. I remember our last hare scramble had a section with a ton of wet palmettos. Traction was tough in there on the tre hundo. 

MXA recently did a writeup on a 350 with the Cylinder Works 366 kit. It was a Gas Gas, so the previous generation, but they made it sound like the best of both worlds. Anyone here have any experience with the Cylinder Works kit?

Have both. 350 collects dust.

I called them but they've yet to get back w/ me.. Not sure if there map is quite ready.  John Ross out of VA apparently has a reflash for the 300- In the aggressive map, mine is way peaky in the mid.  Ima send mine in and see.  I have a PC exhaust combo which really woke it up.. mid is way too much tho, and thus tires you out dang quick/upsets the chassis in turns.

But what about suspension? I’ve had a few Ktm s, & really want to like them but the suspension SUCKS, to pay as much as they want for them then pay a couple grand to get suspension right? I’d rather pay yamaha the extra for a 350, with good suspension!!