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Sounds like a mixture problem to me... pull your spark plug and make sure it looks healthy, if it looks white (lean) or black (rich). then that will give you an idea where the problem lies. I have seen bikes with similar symptoms, and wound up being clogged fuel system (fuel filter, pump, injector).
I had a 2022 Yz250f, at about 15 hours I started having a pretty bad bogging issue when I got on the throttle hard, reducing my power quite a bit. Turns out it was dirty injectors. Sea Foam made my bike run MUCH better almost immediately after mixing it with my fuel.
Yeah....I'm sure you're right....the 250f motor that is basically universally raved about is just a slow turd....got it.
raved about till the damn rod is sticking through the cases.... lmfao
Like i said.... you have to know the setup.... there is companies out there that make good parts for them.
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Thought the Yzf250s came rich from the factory? Should be able to read up and tune it with the app deal
ahh okay.
Making nattys on stock bikes? WHO? i mean making it to the nattys with the stock bike like: loading it in the truck and driving it to the natty is one thing..... qualifying on a stock bike..... idk. I highly doubt that this has happened on a completely stock bike.... if it has more power to them... but that will end real soon after taking that stock bike out on that demanding loam that is ripped 2ft deep!
Like i said..above. The stock 2016 2017 2018 2019 2020 2021 2022 2023 bike is worse than the 2014 model.
Any pro or real b class rider is running dual injection setup on these too...
Someone gets it 🤫
OP: Nobody is saying you suck, nobody is saying there isn't something wrong with your bike, my entire point is your details aren't adding up. That's all. I used examples I have EXPERIENCE with. Believe me man, there are dudes posting on here that most think are basement-dwelling posers that have qualified for nationals in the past 5 years.
There is no effing way you're 85% of redline in 3rd OR 4th and not clearing a 50 foot jump. I don't care how steep it is. Unless you meant 85 tooth rear sprocket instead of 85%.
Other than that Rankin dude, everyone else has given good advice on what to check. I still think something is missing though.
On top of that, since you want to get in a pissing match with me, post the 15 second video.
Yes I said I was out, and also yes apparently I have no self control 😂
I had to go back and down vote all your replies. A stock yz250f will rii riii riiii RIP your house off the foundation.
Also the only things known to be just as reliable is the legendary 12v cummins and the 4.0 straight 6.
Not a chance in the world I interact with a man who claims to have jumped the fly 150 in 3rd gear on a stock 250f.
LMAO! I love it... farmer J your completely correct.. I mean in reality the yamaha 250F is the best 250F out there if built right. but hey what does CW1 and Wossner and carillo and cp know that we dont.... Ahh its for the birds.
Sorry for the double post, but again you are not understanding the topic at all. The topic isn't that I'm unable to hit a 50 foot jump on a stock 250f, the topic is that I'm unable to hit a 50 foot jump on a stock 250f that has some sort of issue causing power loss. Why can you not understand this insanely simple concept?
Take it back to the shop you bought it from and tell them hey god damn it you sold me a brand new bike that’s basically a 125 and have them look it over. A good shop will do it for free if it’s within 30 days of purchase
OP good luck i cant spend anymore time in here or give away anymore Info but just remember there is a reason your manual says to inspect/replace some of those parts... Id be doing cam chains every 10hrs if your a B class rider! thats for sure.
To be honest i think that you have sucked dirt and your valve seats arent sealing.... causing compression loss....
If your not using DT-1 filters and pre filtering the airbox you have already sent this bike to the graveyard!
idk bro maybe go order a pizza
If you think a stock 250F tapped out in 3rd can't jump 150', you're delusional man.
Also you are ignoring my entire point.
I'll go back to the basement now 😉
I'm not letting this go. I need to understand what exactly you mean by what you're saying. I won't be able to sleep at night knowing this man is out there, terrorizing forums across the internet with vague and often confusing points and arguments.
Pit Row
Remember when James jumped Larocco's Leap on a 125 from the grass, not the corner? Maybe that was Travis, actually. Like that. No effing way you're hitting the Fly 150 out of the corner on a practice day on a 250F, absolutely, I'll give you that. Especially with how am's break in the track.
It's a function of speed, like another dude said. Tapped in 3rd on a 250F is PLENTY fast, when you take the corner out of the equation.
I don't even think you're lying man, I just think your explanation is lacking.
Take The Head off and Check if valves and valve seats are sealing.... Your probably gonna need to do that... Then while head is off have sumone re surface it....
then while all that is taking place.... Place an Order for 10X New DT-1 Airfilters and OIL Non Aresol.... and then evaluate the airbox....
On the yamaha airbox its not un common to have to dis-assemble and inspect and clean it every single time you ride it (this and the connecting rod, and the wiring loom are why i switched to ktm.) these bikes require too much for a guy that just wants to ride on the weekends... ALways working on it and hardly riding it...
Good luck OP
Holy shit. One more reason I miss 2 strokes.
His original point is that the bike's speed is dictated by gearing and RPM; a good running YZ250F and poor running one will both be going the same speed on the limiter in 3rd (unless the clutch, tire, or something in the driveline is slipping).
From a quick google for YZ250F specs:
Max revs: 13,500 rpm
Primary reduction 3.353 (57/17) [not certain this is correct ratio but it is ballpark]
3rd gear ratio: 1.444 (26/18)
4th gear ratio: 1.222 (22/18)
Final gearing: 3.846 (50/13)
Rear tire: 110/90-19 (26.795" diameter)
Circumference = pi*d = 84.18"
Assuming you aren't quite on the rev limiter in 3rd and no wheel slip:
13,000rpm x (17/57) x (18/26) x (13/50) x 84.18in x (1mph/1056in per min) = 55.65mph
Assuming you are at 85% rpm in 4th:
0.85 x 13,500rpm x (17/57) x (18/22) x (13/50) x 84.18in x (1mph/1056in per min) = 58.03mph
For reference a 2020 KX250F has a 3.350 (67/20) primary reduction, 1.444 3rd gear ratio, and 50/13 final gearing. I'll assume you ran a 110 tire although I think they came with a 100.
13,000rpm x (20/67) x (18/26) x (13/50) x 84.18in x (1mph/1056in per min) = 55.68mph
Basically, I don't doubt that there is an issue, but I doubt the bike is completely revved out in 3rd as you would be going the same speed as on the KX.
Feel free to correct me if I've made a mistake with my math.
Hows your clutch? is it slipping badly?
For gods sake, you will never get to the bottom of it unless you swap and compare with another bike.
Or take it to a tuner and have him dyno it, and compare it to his baseline.
This is what happens when someone smarter than me makes my point for me! Thank you 😂
I assume when he says he was on the throttle stop (full pin) but did not mention banging off the rev limiter that it was not hitting the rev limiter.
Issue with bike. Both me (165 lbs) and brother (240) on YZ250Fs get over anything. Take the inside rut before the triple at Washougal and get over it. Ive never been even close to the limiter in 4th. That shit is fucking fast
Couple more things to think of while I read through all this.
1: are you running a o ring chain? They create a lot of drag
2: can you post pic of your air filter. I know you said you used K&N filter oil on a foam filter
3: will the bike hit the rev limiter if it’s in neutral?
I only ask because I know you said it only had three hours on it but I’ve had a yz450 have the cam chain jump a couple teeth due to stretching only after ten hours. If the timing is off it will not rev out all the way and almost sound like the rev limiter is way lower.
My buddy and I both bought new crf250r years ago and his was way faster than mine. Found out that my exhaust header to muffler connector was not tightened up.
Nataniel is 100% correct on his take...it's speed that carries you over, not power.
If you're fully tapped in 4th and not making it, then I'd be looking at clutch and or sprocket sizing.
Look at how the FMOTP takes the next 2 massive jumps in this onboard. He gets up to speed, then coasts over off the throttle.
https://www.youtube.com/watch?v=QY_tu4dKWNU&t=93s
Post a reply to: Brand new 250f is oddly slow?