'23 GasGas MC250 or older('15) YZ250

I much prefer YZ250s over the 22' KTM 250SX I had. I think the 23' MC250 is 95% the same as the 22' 250SX. Yamaha suspension is to die for, and that old school neutral handling chassis feel is hard to find in anything else modern. 

That particular KTM drivetrain was the fastest 250 2T I've ever ridden, but it was all midrange and needed to be shifted like a 125. Do it right and the thing absolutely rips. The YZ power curve feels much more broad and linear, and it feels like I can carry different gears better in different places on the track.

My main issue with the 22' 250SX was that I couldn't find balance in the rear shock. I tried different spring rates and couldn't find traction, so I thought I hated the chassis too. I'm starting to think I had a dud rear shock from new. 

Never felt so uncomfortable/unsafe on any dirt bike in my life as that 22' SX, but loved my 2014 250SX, and currently riding a 2024 KTM 4T that I love...so not a KTM thing.



 

I have the 2023 MC250 and put a 300 kit on it (my profile pic).  Easily the best 2-stroke I have ever owned.. and that's going back 40+ years and multiple YZ250's.  Stock to stock, the YZ suspension is definitely better.  The MC250 is horribly soft when stock.  I have 6500 spring conversion forks and did a gold valve and spring on the shock.  It's great now.    As for the power, it's all about the jetting.  The stock jetting is way off and the main cause of the all-mid no-overrev that everyone dislikes.  With the jetting from this thread and some power valve adjusting it's a different bike.  Again, the YZ jetting and PWK is better stock and almost perfect right out of the box.  The GG has better brakes and is lighter and lighter feeling and I prefer the handling.   The GG air filter setup is way better than the YZ's 1980's setup. 😁 Another bonus for the GG is the easy bolt on 300 kit.    So, the GG gas potential to be a better bike but the YZ takes less to get there.

I have been more recently kicking myself in the pants for selling the 22' SX too quickly, and not spending more time trying to dial it in. 

The good thing about the air forks is you can just increase air pressure.  But the valving is very soft in them.  I noticed it pretty bad because the places I usually ride have some decent sized jumps and G-outs.  You could address this much cheaper than 6500's by just doing Gold Valves or some other revalve on the damping cartridge leg.

I personally enjoy air forks as a larger rider, and have since they came out years ago. I’m used to them from mountain bikes, and I like how much hold up they have for me at 215lbs. I’ve had KTMs and Huskys with em’, but never tried GasGas valving. 

That hold up feel does affect small bump sensitivity though. KTM/WP have made big improvements in small bump sensitivity and ground tracking in the newer forks, but the newer forks somehow feel “bouncier” than they act and feel bouncier than old ones. I’ve read/heard that in other reviews too. 

If it’s not a Yamaha, I’m 50/50 on Air VS Spring forks. Yamaha’s settings on the Kayaba SSS are sublime, but I personally think modern WP forks are as good as other spring forks.. they just have different pros and cons.

Gasgas xc, xcf, and sx valving is the same as ktm. It is the four stroke mx bikes that use the ktm euro settings. The sx two strokes also get ktm euro valving on ktm and Gasgas. 

YZ250 all day. Decades worth of parts, R&D, tried and true suspension and engine. Easy to work ok. 

You KNOW it’s going to be good without having to do a bunch of stuff to it.

I have a 22 YZ250X for the woods, and it’s amazing on the track too.

I have the '23 GasGas MC250 (always fun seeing people ask about this bike since it's not common). 

Great bike in general. I agree with the consensus that the stock valving is pretty soft. I'm 6' and ~180 lbs. and the stock stuff is like riding a surfboard on flat ground. Playing with the clickers/air helps a bit but plan on a revalve (by comparison, I've ridden stock KTM stuff before and it's been rideable; GasGas is intentionally softer). I put a Keihin carb on mine and Two Stroke Performance cylinder head (high comp) that helps a lot. Also be aware of this thread that affects that year. The consensus there (and from an engine guy close to me) was the stock conrod design can let go due to the groove cut into the top of it. I never experienced a failure but rebuilt the engine anyway with a Pro-X rod to be safe. It's a fantastic bike now. I run it 50:1 with ethanol free 91-93 octane and it works great. I have a PC system on it but honestly, the stock exhaust is fine (mostly, see below).

As others have said, the KTM 250's dump all their power and then sign off, very little overrev. Exhaust and gearing can change this a bit, but the nature of the bike is "burst of power, then done". Combined with the short, close gearing, you're constantly using the gearbox on this bike. I won't put this as a "dislike", but more "something to get used to".

The only things I don't like:

Brakes (if Braktec): they are noticeably less responsive than Brembo's on a stock KTM. I think in the 2023 line some are Braktec while other bikes are Brembos, but don't quote me on that. Something to check, and also check the clutch slave cylinder if it's a Braktec - I've noticed the Braktec slaves have seals that blow out way too easily. Mine blew and I replaced with the a Rekluse slave which is bomb proof.

Stock Mikuni Carb: Can be made alright with either a jetting kit (my experience) or some of the threads here or on the KTM Forums (haven't tried those, but lots of other back it up). Once I tried a Keihin though I never went back, less fiddling, no weird gasket failures, etc.

(Can't speak about the '15 YZ250, no experience with it; my impression is a YZ is probably less fiddling out of the box.)