How many of you have grinded the welds out of your stock exhaust headers? Also, I just got a dyno jet kit and put 142/144 jets in my quad. I cut the snorkel and I am going to probaly run it with the lid on and snorkel cut. I have a K&N filter on with outerwear. Since I am giving it more air I was thinking about my exhaust. Not to buy anything just modifications. I grinded the welds on the headers and I am cleaning the headers out. I am also thinking about taking the screen off of my arrestor and maybe cutting holes in the 4 metal fins attached to my arrestor. With all this done, should I got up to 144/146 and should I take my lid off?

 

Hey i will have pictures of my whole project soon, this will be edited and I will put them in. I am uploading them now. I took the screen off of my arrestor and grinded the welds on my headers. I am thinking about putting holes in the baffle all the way down in the exhaust pipe. Pics will show you what I am doing and already did. I just need some suggestions. I have 142/144 in for just my airbox mods, should I put 144/146 instead and the punch out baffle or put holes in it ?

 

Try using the search, it works very good. It's the little box above the page numbers on the yamaha page. Type in "stock exhaust" or "lid" or " jetting" and you'll have alot more info.

 

Yea for the jetting, I shaved out the weld on my headers to give it more flow. I am going to probaly punch out the baffle but I dont want this thing really loud. I removed the fine screen on my arrestor. I have a DynoJet kit and I dont know what to jet it at. I am at 142/144 right now with 3 turns out. I was thinking about leaving the arrestor in with the fine screen off and then punching out the baffle. But I never do any forest riding, just in the woods sometimes. I am definetly punching the baffle out all the way down in there but what should I do about the arrestor ? And what size jets? Arrestor w/o screen