Ive been on yz250s since the 90s so Im a little outdated on this new 4stroke revolution haha! Couldn't pass up a smoking deal, so now I own a 13' yz250f. New to this whole 4stroke thing and wonderin if there is anything I should do before I ride it. Break in? Oil ? Any simple cheap mods? Help me out here. Ive been on yz250s since the 90s so Im a little outdated on this new 4stroke revolution haha!
Tips for new four stroker!
- Thread starter jms158bmx
- Start date
TwentyThreeMX
PR Founding Father
13 yz250f is not. i found on my carbed 450s sometimes one blip prior to starting, and then dont touch it when kicking.
GeorgiePorgie
PR Founding Father
the harder you kick a 2 stroke the easier it fires up.
The easier, more fluid/smooth kick on a 4 stroke starts the bike better. I've seen guys wail and wail. And wail. And wail away and can't get it to start. One nice easy kick at top dead center.
Spagina
PR Elite
For my fiance's non-fuel injected rmz 250, my starting procedure is - Turn on gas, turn on choke, 3 turns of throttle - normally starts first kick. if it runs for a split second and shuts off, let it do so - two more blips of the throttle, should fire right up.
on a 250f i feel that the only mods needed is suspension set up (as with any bike) and a slip on exhaust, at least. these bikes are really choked up from the factory and a slip on makes a world of difference without killing your bank account.
on a 250f i feel that the only mods needed is suspension set up (as with any bike) and a slip on exhaust, at least. these bikes are really choked up from the factory and a slip on makes a world of difference without killing your bank account.
Think I might need to rejet. Bike is tough to start up, and even when its warm I can stall it pretty easy. If its at idle and I pin it, itll stall. Even if Im luggin it through a corner and I can make it bog out easily. My buddy bought same bike same day and his runs perfect.
GeorgiePorgie
PR Founding Father
Thats odd. Did you ride his? Because if you can mimick what your doing on his bike then you know the bike isn't the problem...
C Hudak
PR Addict
Check Idle first. Did you Change air filter or oil it. Four strokes don't like heavy filter oil. And after you oil a filter make sure you let it dry up, if you oil the filter and put it right in and run it the oil can get pulled into the carb and block up pilot jets. I used to use the Bell Ray blue filter oil and the bike stalled easy and wouldn't start easy, switched to PJ1 sprays and haven't had any issues since.
I would also check the stock air mixture screw settings.
I would also check the stock air mixture screw settings.
C Hudak
PR Addict
I wouldn't touch the jetting until you get the filter cleaned up. Ride it at least 5hrs to break it in and see what its running like after that. Usually they stall easy and hard start the first couple rides, then when the motor loosens up you will have to turn your idol down, because its running so much better.
baxterj787
PR Addict
Hudak is on the money. I used the blue Bel-Ray. Let the filter drip-dry overnight, then fire the bike and install the filter with the engine running. I never had a problem.
One big word of caution regarding the adjustable mixture screw: When you remove the original mixture screw, MAKE SURE you get all of the original hardware out of the carb body with the screw. There will be the screw plus a spring, a small flat washer and a small o-ring. All these parts (spring, washer and most importantly the o-ring) will have to go back onto the new fuel screw if the new fuel screw doesn't come with them. The bike will not run right without the o-ring and washer, and they are very easy to miss during removal.
One big word of caution regarding the adjustable mixture screw: When you remove the original mixture screw, MAKE SURE you get all of the original hardware out of the carb body with the screw. There will be the screw plus a spring, a small flat washer and a small o-ring. All these parts (spring, washer and most importantly the o-ring) will have to go back onto the new fuel screw if the new fuel screw doesn't come with them. The bike will not run right without the o-ring and washer, and they are very easy to miss during removal.
Good to know. I orderd the fuel mix screw so hopefully that will clean it up. I rode it hard for the first time at smith the other night, and it still runs like crap. First time Ive been to smith rd in bout 10 years, and I loved it! I was gonna use this bike as my trail machine, but man it was fun on that track!
loneranger171
PR Addict
I don't know how the yzf newer bikes are.... But hope you don't need to change spark plug on the go.... Can't even see it on my ktm 350....damn technology!