yeah, i have a 2001 stock raptor with no mods cept i took the filter outta the exhaust, anyways i was wondering if there is any way i can make it better, faster w/e, without buying kits or anything, i asked my dad about a jet kit? he said it feeds more fuel to the carberator and says it practically does jack all, but anyways can u guys help me out?? thx

 

Next time your at the Yamaha dealer buy yourself some Mikuni small round jets, sizes. 150, 155, 160, 165, 170, 175. Take them home, remove your lid to the air box. Where the filter is installed, there is a flnge that fits in a slot on the bottom of the box. Make sure that is secured in it's groove. Then drill 2-3 holes through the flange on the top of the filter through the air box and bolt it to the airbox securly. Make sure the filter is tight against the airbox and no gaps to allow dirt to pass by. Take those jets you just boiught for aprox $2.50 each. And install them into your carbs. Put the 155 in the left carb and the 160 into the right carb fi you are below 3000' elevation. If your above 3000' elevation you might be ok or you might have to go a size smaller. Get out and ride. If you have stumbling and bumbling when you try to take off you'll need to go up another jet size. If you get going and are wide open on the throttle in 4th or 5th gear then return the throttle to 3/4's and you have a stumble you'll need to go down 1 jet size. You bought an assortment of jet sizes because when you take the lid off you'll need to rejet. Without trial and error you won't know which sizes you need to get it right. This a cheap way to gain a couple ponies. DO NOT run without the lid on your air box unless you bolt the filter flange to your airbox or better yet buy the $100 pro design filter and flange. It would be best to do some plug checks to get thje jetting right. Do a search for plug checks on this site. Good Luck.

 

k ill try that muffler thing first, thanx guys, keep em coming