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The guy that told me that rides a ‘18 250SX. He said his bike throws out tha anchor and the 300 keeps going and going. It also feels more powerful to him. I guess he is FOS. Do they Teflon coat the underside of the piston? Lmao!
He likely was still running the ridiculous stock slide in the 18 carb. Yes, they fall off the power with the stock jetting. Keep laughing.
Yo Brainiac, the slide only effects 1/4 throttle operation.
Guy who runs the channel is a character but 23 & 24 300's have had issues with the intake side of the piston skirt hitting the crank under high revs.
https://youtu.be/nsGtopKqwxg?si=M5wsYOeaFcayi_bd&t=487
Alot of info on this thread as far as measurements on the new part numbers etc from vertex to fix this issue.
https://www.vitalmx.com/forums/tech-helprace-shop/2023-ktm-300sx-potential-issue-pics-and-video?page=2
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He did mention if these bikes are not reving out it’s a mapping issue. Once it’s corrected they pull long.
Correct - My 23 TX300 with TSP ERM pulls much better than stock. Tune completely changed the bike.
So in Mr. Thompson’s case he should verify they updated the mapping and piston part # for ‘25. All this falling on their face and grenading is vitard hyperbole.
Keep your vintage Yz for nostalgia….also good practice for transmission rebuilding and clutch replacements. If you are patient, you can likely pick up a low hr clean 300SX from an old guy that thought he wanted to feel 2 stroke power again and realized they require more effort to ride than a 4T. With a remap the 300”s can lug and rev on top. 110 hrs on my 23 300SX, Vet/Sr A rider, most of hrs were in deep sand… just replaced piston as preventative, could have ringed it… inspected clutch plates, still within specs….I would rather play with air pressure in my forks than replace transmission gears…. If my dad owned a yamaha shop, I might by a YZ…maybe…
Keep the YZ. And if you want a new bike, you can look for a new YZ 250, or take a look at the 2025 Beta RX 300 (electric start, carburetor, premix, Kayaba suspension). Anyways, I believe that the YZ 250 is the best MX bike ever made.
Obviously you haven’t ridden many 300’s. When compared to a 250 they don’t rev out nearly as much. All the power is in mid rpm’s. Which is fine if you like that kinda motor. For me it’d be 250sx all the way.
Or he doesn’t know how to jet a carb worth a piss. The 250sx carb motors were rockets. The dimensions of the bore and stroke on the 250 are more suited to high rpm power when compared to a 300.
I really like the power and suspension on the YZ250. Very refined and easy to tailor to your needs.
The counterbalanced engine is a real improvement. I've really been watching the TBI 2-strokes as a replacement for my '17 TC250.
And Munn sent out an e-mail blast yesterday: 2024 KTM 300SX for $6390.
24 300sx for $6390 is a STEAL
There's no physical room in my garage for another bike and I'm working hard at talking myself out of this.
Is that price shipped?! Doubt it
Sure he doesn’t . Nothing wrong with his 250. He talks all the time about how good it runs. What he said was he needed 4th in the same sections he could run 3rd on the 300 and that they rev out further. But you see he it actually out riding these bikes every week instead of not doing it and taking to the internet to tell folks who do they don’t know piss.
You have also had 3 owners in this very thread state the bikes rev out well. We are all wrong and you are right. Yet, you say I am the one who can't have a reasonable conversation.
Remap the 205/300SX stock ECU from Twisted, not even the same back. Before, everything about the KTM is superior over the 18 year old bike, save for the engine. Now, it's no question.
I liked my 23 300xc and love my 25 300sx. I feel they do benefit from a pipe and silencer, I used FMF on the 23 and have PC on the 25. Helps a lot with over rev, the bike doesn’t need more power in my opinion. Comparing it to a vintage YZ is hilarious to me. Lots of people commenting have never ridden one I’d guess.
Pit Row
FGR
I’m running a 21, love it but it falls off up top.
What’s the jetting you speak of? I will try it
Thx!
And we’ve also had people say the 300 doesn’t rev as well. And that has also been my experience.
Funny I have not see a single owner come in and say the bike won’t rev out with a proper map. Maybe you just ain’t twisting it hard enough. 😉
I have a 2011 YZ250 that Tom Morgan worked his magic on and it is now a 295. By far the funnest bike I have owned. The motor is amazing. I have ridden some 300 TBI and TPI's and was not impressed overall.
If I was to upgrade I would probably go the Sherco or Beta route. Stick with the Carb until someone figures out something better.
That’s obvious because your a moron who only sees what he wants. From Suspensionguy on page one when talking about them revving out.
‘I own one and can assure they do not. In fact in stock trim many dyno’s have the 300sx making less power then the prior gen 250sx, not to mention its 15lbs heavier then the 19-22’ 250sx, weights more then a 2022 450sxf but everyone ignores that lol ’
Also ironic you say i havent ridden one (I have) then go on to say ‘from everyone you’ve talked too’. It’s obvious who hasn’t ridden one.
I don’t think you are intelligent enough to be able to have a nuanced conversation to be involved here so maybe sit this one out.
Or maybe he didn't update his map?
Pretty sure the new piston is the same dimensions, just a different supplier, which doesn’t fix the rod/skirt clearance(300) or the detenation issue many are seeing. Lots not knowing they are detonating and grenading their motors. It’s absolutely not vitard hype. Go scroll the TBI Facebook groups, you’ll find post after post of grenaded motors and running issues, more so then any other model specific, probably more then all other model specific groups I’m apart of combine. Mine was detonating on the first 3 maps I had, currently on my 4th remap, now set up(head & mapping) for 92/110 mix and it’s finally good but I still don’t trust it to pile hours on like I have my last 5 250sx, I normally do well over 100 a year on them, this tbi has under 70 in two years, that’s saying something if you knew me.
Or maybe you have no clue what your talking about because you haven’t ridden one.
20 pager in the tech section. The specs did wonders for my '19 125sx.
I don't see how anyone could ride a counterbalanced (2017 and newer) Austrian 250/300 2stroke and not think it blows away the other vibrator bikes. Maybe I'm just sensitive to it.
Didn’t know if he was referencing that or some other magic… I had run the 17-62 as an alternative and that was great also always looking for alternatives….never satisfied
I guess none of the other owners that agree with me have a clue either. Or the guy in the video that builds them for a living.
Post a reply to: Keep my YZ250 or KTM 300 SX?