ok well about a yr ago my buddy bought a new yfz450 and he only rode it maybe 5 times and then he didnt have a place to keep it so i i decided to let him keep it at my house ,well this time last yr he took the baffle out and threw it away and we went riding out in the snow for shts and giggles well i noticed his pipe was cherry red so we took it back home and stripped itdown and cleaned the carb and put it bck together and the same thing , well i ended up leaving town for school and i come bck and i still have this quad in my shed what a shame right he never picked it up or even tried fixing it , well i just found out he got a grl prego so im ending up getting this bike that i have riding more thn him for under 3 grand one hell of a deal i thought so i was wondering if any of u know what jets sizes for il and indiana riding would be and maybe help me out with which pipe to get , i was thinking of curtis sparks,fmf fac 4 or even i have looked at the ltr true twin pipes or even a lrd . i have other friends that have yfz with pipes and there all jetted and got k/n filters and there head pipes are getting cherry red or even crazy white but htey have mny to spend on a new bike like it ant nothn and i dont , there all new to riding and have parents with gobbs of $ so they dont care about there bikes at all and i have to try and keep up with them on my 400ex at the moment and i get blown away once we hit open areas but in the trails i can out ride em so im basically trying to get this new yfz set up soon and give them all a surprise adn make the riding more fair on my part . thanks scumboy

 

from the factory those bikes are super lean. I would try jetting up a size or two and moving the needle clip down one. Dont worry too much about the glow, even when jetted properly it will glow like that. Over the weekend I was at glamis and I have my bike too rich and the pipe was still glowing red. Normal and not something to worry about unless the bike starts to overheat

Aaron

 

What all has been done to it? Just the Baffle out??

What about the airbox lid??

Still at stock jetting??

 

yea its just a stock bike at the moment no mods at all other than a few cosmetics but yah just the baffle has been taken out nothing else ,

 

Put a 165 main in, a 45 pilot, and try the needle clip on the 5th position.

 

to stop the exaust glowin red, raise the pilot jet to 48, if it starts from cold with the choke off then its too big, put a 45 in should work, if it still starts from cold with no choke then screw the fuel screw at the bottom of the carb in half a turn.
as for the main jet, start big like a 182, if it splutters at high rev then go down a size that suits

 

You are kidding right???
a 182 main jet for a YFZ that still has the lid on, and nothing else done but the baffle removed??!!??

Ive got an aftermarket exhaust, lid removed, and I am only at a 172!![img]i/expressions/face-icon-small-disgusted.gif[/img]

 

well im over in ireland here, maybe the petrol is higher here, i have a full alien exaust with airbox lid off and run on a 182 main jet and 45 pilot, goes v.well!

 

What needle you running? Stock? Aftermarket??

What clip position is it on?

What is your fuel screw set at??

 

Hey 2fun....left a reply over at the other forum about sand lake. need to hook up with some of you local peeps, me and yfz450guy got together yesterday. listen to 2fun, he is right. stock set up 45 pilot, 165 main, drop clip one position from stock and set fuel mixture around 1.5-2 turns out. this should be good for 0-2000 feet elevation. any higher and you will have to drop main jet size. cold weather you may have to increase main jet. good luck