2007 yz 250 jetting???

I just bought a 2007 yz 250 2t. The bike is very clean with very low hours. I just installed a fmf gnarly pipe and titanium 2 silencer. The bike seems to run great but I'm getting some spooge from the silencer . I still have the stock jets in it. 178m, 50p, 2nd clip on needle. I have a boyesen rad cage coming and plan to install soon. I'm a new to two strokes and have been spoiled with fuel injection. Two strokes are so much more fun. I am in Louisiana so I'm at sea level, 75 degrees f. Should I got up on main jet or down? Up on pilot or down? Up on clip position or down?. I'm also getting some oil coming from powervalve when parked. Not a lot just a couple drops. 

I have an 05. When it was a 250 I installed a JD jet kit and a #8 slide. The bike ran awesome at 4000 ft to 5000 ft in the CA high desert. The #8 slide fixes the 1/8 throttle burble. (Mines a Max Power 285cc now)

On 18/11/2017 at 1:29 PM, Nicknickranger said:

I just bought a 2007 yz 250 2t. The bike is very clean with very low hours. I just installed a fmf gnarly pipe and titanium 2 silencer. The bike seems to run great but I'm getting some spooge from the silencer . I still have the stock jets in it. 178m, 50p, 2nd clip on needle. I have a boyesen rad cage coming and plan to install soon. I'm a new to two strokes and have been spoiled with fuel injection. Two strokes are so much more fun. I am in Louisiana so I'm at sea level, 75 degrees f. Should I got up on main jet or down? Up on pilot or down? Up on clip position or down?. I'm also getting some oil coming from powervalve when parked. Not a lot just a couple drops. 

45 pilot 

research Suzuki needles 

down on the main

what oil do you use and what ratio ?

I plan on using klots 40:1

Only reason to buy the JD kits and spend the $ is if you want his needle otherwise it is a waste of $, still might be a waste if you just want the needles as well, ask around, someone might have a needle laying around they don't want and will part with cheap.  I have one of his needles laying around but can't remember which color but know it is not the stepped one but it is not for sale either way as i might try it in my 250x next season but someone might one for sale for a good price. 

Go to a 48pj and a 175 for sure to start out with and with the stock needle in the middle.  You could probably go to a 172 with no issue but it is getting colder out, not sure where you are in the US so i would try the 175 first.  See how she runs at WOT, if it feels pretty decent, mess with the needle and pay attention to what the bike tells you and adjust accordingly.  

You could try the zuk needle, lots of people seem to like it, but notice some people never get it to work 100%

I never had a problem with the stock slide, but either way i would save that for last as you might not think you need it.  Slides cost around $60 + where as jets and needles are $5 - $10 :thumbsup:

I man in Louisiana so I'm at sea level to 100'. I'm at a 178m,50p. Ran awesome with stock pipe and reeds. I changed to fmf gnarly and boyesen reeds. Should I still go with a 175m and 48 pilot?

did you just change the reeds or is it a whole boyesen rad valve?  If you install a rad valve Boyesen says in the instructions that you will have to drop the main typically around 2 sizes from where you are with the stock reed cage.

yeah, you should be fine with the 48 175 especially at those temperatures. 

Both FMF and Boyesen have "recommendations" on jetting when changed from stock. It's on their websites.

Look at plug color and post pics! Pilot jet is low end, needle is mid, main jet after that! Are you racing or just riding?

Just installed the boyesen rad valve and WOW!!!! I love the power of the bike even more now. It is more like a four stroke but still has the two stroke feel. It flat out pulls every gear. I ordered a fly wheel weight to install and use in woods but I don't think I need it now. I'm not sure I want to tame it at all.

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