2013 YZ250 jetting question....

What jetting was he running in the 12 I think my jetting is a n3cg needle middle clip 175 or 172 main depending on where riding 45 pilot if your torching bottom ends your doing something wrong real wrong like never changing gears I run motorx oil they say its not that great but it looks like new when I pull it down 500ml to 20 l

A good place to start is to look at the spark plug. White your too lean, black your too rich somewhere. Should be brown.

I have a PC pipe on my '06 YZ250 (which has an identical engine, as far as I know.)

I went one richer on the main and I am running the provided alternate (leaner) needle in the 2nd position. Your buddy may have to rejet for elevation and humidity in New Jersey, but he should be close using that combo.

my 12 has stk pilot stk needle pos, and 178 main straight vpc12 w motul 800 32-1 stk timming, fmf plated fatty, stk or power core 2 siklencer, in new england (sea level) vet a rider

Stock jetting is pretty damn good on these if you are running the recommended 32:1 ratio. Only change I made to mine is I put in the N3CJ needle in the #2 slot. It is half a clip leaner than the N3EJ which came stock in the 2006 and earlier (and is probably the optional leaner needle with the newer models).

Get some decent fuel before you worry about jetting, first things first. Stock jetting is not that far off.

Most of the time you need to go a bit leaner when you add a pipe. But in NJ, temperature comes into play. You need to jet fatter when the temps drop. It's cold up there. Running lean in colder weather is going to blow your motor. In NY, we changed the jetting for temps between 60 and 80, and went even fatter in lower temps. I always ran 32:1 ratio. Higher ratios produce more heat, and more friction. Not a good combo with a lean jetted bike. Always run 32:1 mixture for the gas. Then, you need to do what the pros do. Test. Ride the bike, see how it runs, look at the plug, and make changes until it runs the way you want. A little change can make a big difference. It takes time, and is a pain, but it pays off big.

X 2 pump gas is such garbage , need to have 50 % race gas mix to really know whats going on .