Ok so I need some help as to what is going on with my 05 YZ250F. So I just bought the bike and it’s pretty much new! Has less than 15 hrs of riding on it! Bad news. The previous owner left the fuel in it and sat for 3-4 years or more. I cleaned the carb twice. Seemed to be getting better after both but then said enough and bought new jets. So the deal is. The jets I ordered are from al”all balls” I do believe. Well the sent bigger jets. Sry. I never wrote them down but anyways I’m new to the bikes and I’m pretty sure it just needs tweaked. Where to start? Sry so long!
250F Tuning? Idle?& carb
- Thread starter Montey0211
- Start date
Yes I bought the jets and installed them. Like I said for some reason some were bigger than stock. There for 05-07 YZ250F so I don’t know why. Starts within a few kicks and I’ve never messed with valves before. The bike has less than 15 hrs on it. I don’t know if they can go outta whack being it’s pretty much new. And air filter is ok.
Sounds alright.
So what’s the problem? Starts easy, it runs well, maybe some hiccups in the throttle response?
Go to your local airport and buy a gallon of 100ll. Also known as Av gas. Throw that in the tank and see if it runs better.
Well not a hundred percent running well. It dies with quick throttle and ok if applied very slowly. Also a lot of popping. I don’t know if it’s a lean big or rich?
Pretty much new as in barely ridden. Has not even 15 hours of ride time on it. It’s been sitting for it’s whole life and just moved around.
Wow I would love to see some pics of this machine! That’s a great find as this bike has a solid reputation 10+ years later. I would have to guess then your problems are still carb related. There are several passages that need to be clear in addition to the jets themselves. I would use the stock size jets as a baseline for tuning. Popping means too much air or not enough fuel. Does it pop on decel with closed throttle only or does it pop and miss when youre on the gas?
Yea I ended up stealing it! Wife’s step dad, too much money to know what to do with it!! 700$ for a machine with nothing on it!! Count me in. So anyways I’m in pa and there’s still two feet of snow so I can’t get it out. I can get it up on a stand though if need be. This is my first bike and I just don’t know what to do. I’ve cleaned the carb twice! Got an all balls carb rebuild kit. And still just don’t run right on idle. I mean it prob just needs ripped on but unsure and don’t wanna hurt it!! So any help is appreciated!! Btw the dirt on it is from 2005!
Nice bike! My shit phone won’t let me upload a pic but all stock. So anyways I have the carb apart right now. Stock jets. Pilot-42. Main-182. Leak-72 and unknown in the body itself-100. The rebuild kit came with p-42. Main-178. Leak-75. And unknown-105. Any suggestions? I was about to just put all stock in and see what happens. Of course clean again!!
Ok wrong number on the leak that is the slow jet I believe. And the leak is stock 90 and kit cane with 80
That's the problem with kits. They are multi year, and may not have the right jet or two in it. I buy the carb kits all the time, but make sure the jets that go in are correct for year, alt, and needle in some cases.