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After reading all of the replies I am leaning towards a slipping clutch.
Take it to Varner
Is it banging off the rev limiter?
Check the tension on your clutch cable. There should be a tiny amount of free play in the cable before it’s starts disengaging the clutch.
a slipping clutch is easy to notice from feel and sound the engine makes.
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soggy is right. clutch cable tension is key
Can we get a video of you riding?
I wanna see Pro Circuit kawi's new fill in rider.
Reposition the way you grip the throttle, you’re most likely not WFO
If you put a wossner rod and del west valves on a yz250f would you say the reliability would be on par with ktm?
There’s no way you could read this threads and think that’s the problem 😂😂
My son did it in 21 on a YZ250f and on a Gas gas MC250f in 22. I'm sure plenty of others have too.
ive had a problem one time i used spray on air filter oil. never did that again. after changing that i would try a buddys gas
I know you think I'm a total jackass, but if I had to make ONE guess why that bike feels slow/different to you, it would be a clutch problem. It's about the only thing that wouldn't be immediately apparent based on a sound difference.
One of the mxa guys did it last summer on an Rmz-250. I think it even had stock valving.
I dunno. You see pros with very short run at a supercross triple and sloppy mud before the jump but face is dry and they use all that 450 torque going up face to clear the jump with no run at all. Pure power
Still speed, but need the power for the short run. Takeoff speed remains constant.
Yep, acceleration is needed on a short run up (which is what makes these bikes so awesome to watch) to get to the necessary speed to clear.
Just like the seat bounce myth...riders aren't compressing the rear to catapult/spring themselves over a jump with spring rebound...the rebound damper prevents anything like this from happening anyway. They sit down and compress the rear for added traction/max acceleration over a shorter distance.
I don't own a YZ250F , or any 250F , but this sure sounds like a mapping issue. Hope the owner gets it figured out. That's one great thing about all these new 4 strokes , is you can play around and make it feel like 20 different bikes.
I have a 4.0 straight 6 in a 2001 Cherokee I picked up last year for $2,500. Only had 130k miles. Great vehicle.
Pit Row
I would check the clutch play first.
If it's not the clutch slipping, and the engine can hit the rev limiter, and it's been this way from the factory, is it possible that the timing chain is a off a tooth? I have no idea if a modern 250F will even run in this situation.
I've seen this happen far too many times on friends' cars over the years. They run, but run like crap, with no power.
I once left a rag in my air box and couldn't start my bike the day of the race. Tried everything before my dad said to take off the seat and look around. Oops
OP, is there a rag in your air box?
Me too. I even towed my bike behind my friend's van trying to start it. I was about 14 -- no Dad -- and I didn't figure it out until I got home. I'm positive that I was going to win and get a team green ride or something that day too.
This has been a good one
Trail riding as a break in procedure is too mellow. It probably cost you 3-5 hp.
http://www.mototuneusa.com/break_in_secrets.htm
I don't think I've ever read a post with such shit advice. Ever. Check your grip on the throttle? Are you serious? Dude claims to be a B rider, pretty sure he knows how to grip the throttle and what wide open feels like.
I would start by seeing if the dealer will do anything. If they're going to charge you hours of labor to find nothing, then I wouldn't go that route but if they'll look it over free of charge being that it's a brand new bike, then go that route first.
The lack of power and backfiring makes me think it's fuel/time related. Could potentially be valve timing and that's easy enough to check by pulling the valve cover and lining up the timing marks. Probably a slim chance that it jumped time being brand new but there's a chance.
I'd also check the plug color like previously mentioned and get an idea how it's burning. If it's sooty and rich, it could potentially cause some popping and backfiring and that could be leaned out with the app. I'd probably return all fuel and timing maps back to stock just for a baseline.
As long as the wheels sling freely and there's adequate free play in the clutch cable, I'd say it's definitely engine related
Also, how many down votes on every single post do you have to get before you're just permanently banned? Asking for a friend
How many posts on "your clutch is slipping" are needed. Jesus h christ .
This thread is unhinged lol.
I normally would 100% agree with on this point but if you watch videos of this jump it's a steep uphill triple with not much of a lip.
On my 250 I would deff have yank the throttle to clear it. It's not one of those just hit it with speed jumps.
Any modern 250f with a healthy motor should be able to clear this jump no problem.
Thoughts on that page? I'm about to break in a new top end soon and I must admit I hesitate because it is "against the grain"
They are all "hit it with speed jumps." You can manipulate your trajectory angle multiple ways via loading your suspension, scrubbing, sucking up with your legs, etc., but for a given trajectory there is a given required speed baring a change in outside factors (like headwind).
Post a reply to: Brand new 250f is oddly slow?