350 vs 250f With Mods

Seems like it would be tough to make up the amount of power you give up. You can go fast on a 250 as well you just may have to work a little harder. Gotta ask yourself if the cockpit comfort is worth giving up some powah. Edit: Just noticed the YZ and SX engines both make peak power at 8900 rpm, huh cool. Very similar power curves.

How much do you weigh? I don’t recommend a 350 or 450 to a true novice rider. The Honda power delivery is better for a novice rider than the kx250. It isn’t as stable when really pushing it though. 
 

What part of ktm ergos are the problem?

Vet B rider here. 185 pounds. 
 

In the past 4 years I’ve had 2 450’s, a 250 2 stroke, and a 250f. I’ve also had a 350 in the past.
 

- 450’s own 95 percent of us. I’m not afraid to admit that I’m not within the remaining 5 percent. 
- The power of a 350 is perfect. Especially for a heavier guy like you. It just comes down to whether or not you are comfortable with how the bike handles. 
- My most recent bike is a 250f. Yes, it feels slow compared to a 450, but I’m just as “fast” on it as I was on the 450. Plus I feel more in control. for context, I put a pipe, ecu, and added a tooth to the rear. It hauls me around fine. 

Best of luck making a decision. 

Vet B, 6'3", 215#.  I prefer my modded 250F over my 350 most of the time (fresh, deeply ripped tracks the 350 gets the nod).  Grab the CRF, put a big bore kit and mapped ignition and enjoy!  

As a mid pack Vet C rider, I don't think you need to worry so much about how many CC's your bike has, or how much power it has (none of those bike will be slowing you down at all) and just make sure you get a bike set up for you (suspension), that you feel comfortable on, and for the riding that you do (motocross, off road, etc.)...and then spend all that money you'd of spent on mods on as many riding schools as you can...as a novice rider, improving your technique and riding ability will help you go faster than an extra 30 or 100 cc's or an ecu, exhaust, or head ever could.... 

I’d go with the 350, I’d have one if I thought I could get the suspension working without going bankrupt! Lol, the 250 does have enough power for most people, unless you’re starting against 450s, or come up against another rider the same ability as you, on a bike with more power, then you’re at a disadvantage, at least with the 350 you’d have a chance! 
just my opinion! Good luck 

No replacement for displacement 

In the C class there is…it’s called technique…

Body weight has everything to do with bike choice, regardless if you're a novice or not. For every 6 pounds of body weight you lose 1 horsepower (I think). So you are down the equivalent of 9-10 horsepower compared to a 160 pound rider on a 250f.
 

The 250f has come a long way but its technically still the equivalent of a 125 two stroke. Looking at the power curve posted above, you're going to have to be running a yz250f at pretty high rpm's to even make somewhat comparable power to a full size bike. And when you're running a yz250f at those rpm's, probably going to throw cam chains, drop valves and so on if you're not taking it apart every 20 hours. 
 

In my opinion, any weight above 185 pounds you are just too damn big for a 250f. Especially if you're riding a track with hills, mud, or any deeper type of soil

Surely a 350 with a spring conversion kit or whatever the banging setup is would be cheaper and more reliable than a 250 with a big bore and supporting mods?

Lol yeah that’s fair

Surprised you feel that way about Ktm ergos, most feel that way about the Yamahas.   I’m 6’3” and all I do is put fastway pegs in the low/back position and move the bars to the forward position and it’s plenty roomy. I’d certainly be willing to work on ergos myself rather than trying to mod a 250 to run like a 350.  You’ll end up with shorter service intervals and you’ll never equal the power anyway. 

Vet A deep sand start on a Husky 167 beats x pro Vet A on a 270.  R you sure that yz250f chart is correct? Seems like low #,s 38.9 & 18 ft torque. My National 04 cr125 is similar but higher torque. 

I concur...  Every dyno reads a little different, but almost all of them are a bit over 40hp.  But I guess in reality that's only a 5% difference.  

You just want an excuse to buy a new bike?

Dude you should try a 250f.

There is, it’s called corner speed.

Because 450 handle worse, the power can be needed to pull you out to slow corners, 250f can be ridden with greater flow, so you don’t need the extra displacement to be the same time around the track.

Even at pro level, how often do we see much less experienced matching or even beating 450 pro guys lap times. 

I think if you want to be better rider, just get a 250f, get the gearing & sussy  right to suit your weight, then learn better technique.

When 250f first came out 20 years ago they had enough to clear GP jumps & beat 450’s. It’s all about learning to ride a bike to its strengths & characteristics. 
 

Best advice i'm gonna give you and you won't regret it, sell the 350 and buy a 2022\2023 250 YZ-F, put a GET/vortex ECU, full exhaust, twin air cage and bigger carbon airbox. 

This is what i did in 2021 and it was the best decision i ve made, i didn't gel with the 350 husky at all and loved the yami 250f with mods ! 

The yami 250f is the best 250f donw low and mid punch you can carry 3rd gear eazy and so on but know one things, the 250f will never be as much powerful as the 350 ! The 350 makes some serious poneys stock, but it doesn't mean you're having more fun or you're being faster on it ! 

You can check my bikes under my profil 

I agree. That is also what I did and do not regret it. I am probably going to also install a GYTR head on my YZF just to get a bit more w/o over-stepping that line of reliability. Even with those mods, the 250F will never put out the peak power of a 350. At different points on the dyno curve, it's actually crazy hiw much the 350 gaps a 250F in power. That being said, it doesn't always transfer to the track for me. On faster tracks, the 350 is perfect. But tighter, rougher tracks etc i find the 250F to be a lot easier to go fast on. I just like the power profile of the YZF, along with the suspension/chassis. I dont have much experience with the CRF or KX but i think if you dont go crazy with mods, but get them nicely set-up, youll be fine. 

So the answer to a bike with poor ergos for tall people (I don’t know that I agree this is a problem on a ktm, but I am not tall) is a bike with worse ergos (yz250f) for tall people?

At 6'3" I would suggest the Kawi. They gave the bike a bit more bottom power this year and smoothed it out (not really a fan as I like the harder hit of the earlier bike). I can't dream you would need any more power. Call Enzo and live happy ever after. They will cure all the handling ills the shootouts complain about. Don't talk smack about the 350 being a tweener bike of you will get butt rushed by the Vitards.

No but if there is 1 250F that I've seen former 350 owners go to, it's the YZF. So just making a point that for certain people it can be done without feeling like the bike is way down on power. I'm sure the same thing can be done with a CRF or KX but I personally haven't ridden the newest versions.

See, this is where I'd go an entirely different route with a novice/C rider (maybe even many B riders, and possibly some slower A riders) who is trying to get faster/better results on race day...a C rider would go faster on a bike by learning how to ride the motorcycle correctly...he'd go much faster than spending a bunch of money on motor mods...so like I said above, if I'm the OP...I'm buying a bike I feel comfortable on (ergo's), setting up the suspension and then spending the money I'd of spent on all those mods on a gym membership and riding schools....learning how to ride a motorcycle correctly (cornering, standing, throttle/clutch control, proper braking, body position, breathing, etc. etc.), practicing that technique until it becomes muscle memory, while improving my fitness to be able to ride a motorcycle correctly for two 4 lap motos on race day...

It's a virtual guarantee that a novice/C rider would do better (go faster, better results) doing that...than just making his bike more powerful...

Unless, of course, he's not concerned about actually going faster/improving results...and just wants to bling out his bike, and can afford to do it (and there is NOTHING wrong with that at all)...or can/wants to do both (improve technique and mod a bike)...in which case, more power to him!  Thanks for supporting the sport! I think thats awesome!

Repeat after me: "Comfort before power. Comfort before power. Comfort before power." 

For me, this is an iron-clad rule. I'd rather race a 125 against a full field of 450s than be on an uncomfortable machine. 

The 350 is pretty damn versatile.  I have one and it's a really fun bike to ride.  I also ride a KX450 and i chose that bike as my race bike.  In a race....it's too hard to pass coming out of the main line with the smaller bore bike.  I have a fully modded CRF250 that i ride indoors or for the stadium tracks that we have in Illinois.  It's a 2013 though so it's pretty chuggy if you know what i mean.  I have ridden a fully modded Pro Circuit KX250 and the bike was awesome.  It revved so freely and was fast as hell.  To get it to that level though.....it took a shit ton of money.  Not a great value but a hell of a fun bike.

My rule also and every pro thinks the same way. Once there comfortable they win. That’s why I chose the 04 cr125 by far the Best chassis ever built. Jeremy at Mx Tech will tell the same and you can drop a 250 or 500 engine in it. And it’s still awesome. All you need is 36.5 hp Stew proved that . But you hv get b a Great starter and get crafty. If you can’t get a better jump off the gate than others. It will b tough. Just start next to the fastest guy and cut him off. Put the fastest guy behind ya on the start and you control the race. 

These are all valid points and good advice. I agree with all of that but just looking at it from a different angle.

The gym, riding school stuff is besides the point, to me. He may or may not be doing those things. The question was bike specific, so I answered just about bikes. Another thing that I sometimes don't agree with (in general, not you) is people see Vet or C and assume the person is a terrible rider or that someone that level doesn't need to change whichever bike, whether it be more power or whatever. I think riders of allevels can/should know what works best for them. They don't need to be an elite talent that uses everything the bike has, to want to make changes. So if OP thinks he would rather have a CRF but is used to 350 level power, i think going that route can be done. Make sure the suspension is dialed and any other mods that may move the power around to his liking, are still very effective at his level. I'm not suggrsting a big bore or full-blown pro national build. But maybe gearing, exhaust, ecu or whatever the hot set up is for those bikes (i only really know the Yamahas, as mentioned before.) I think getting the right bike and dialing it in is always something that should be encouraged.

I watched a part of Bubbas World with Ricky. Both said the same comfort zone , they rode above it at times but knew the big crash was coming. If you hv a chassis that can handle a gear higher than another bike and b in control yet. And your comfortable going ovr the edge. That’s hard to beat.  The winningest basketball coach John Goodman always picked quickness ovr strength.  

Exactly what I was thinking! The YZ is terrible for tall people. 
 

This year I switched from a YZ450 to a KTM 350- transferred over my KX Tall pro-tapers and bought the taller seat and the ergos are good for me (at 6’3”). 
 

Had the chance to ride my previous YZ450 and realized how bad the ergos were for tall folks (granted I never did put a taller seat on it).