Wierd Jetting?

[Foxhound013]

Ok so I got a 2002 crf cam in my 2005 450 and we built a slip on for it. My dad had a rossier slip on for my year so we based all the measurements off of it. After getting it all back together we jetted it to about 160 and it was to big so we went down and ended up at a 140 pilot 48 and a/f 2.5 out. Now the only thing that dosn't make sense to me is why does such a small main work way better than the larger one did. I think almost every time ive ever read of someone even just putting on a slip on they at least put a 155 as their main. Any ideas?

[d3ktrix]

Did u remove the airbox lid?

And 05 with the stock carb, airbox lid off, and a opened exhaust should be somewhere around a 185MJ.

And post pix of the home made slip on, I always love seeing custom stuff.

[Foxhound013]

I'll try to get a pic for ya soon. The lids on because I race xc so I wasn't taking it off. It runs good at a 140 MJ and that seems way to small. Dunno why it works with such a small jet.

[d3ktrix]

That is why the 140 works, that is normal with the air box lid on.
You are costing yourself a few hp by keeping it on though.

[Honda4life05]

140 sounds perfect, i'm runnign a 138 with your setup

[Foxhound013]

I take the 140 back, its a 138 like yours. For some reason I thought it as a 140 lol. Now it makes sense. I may try to go buy a lawnmower filter from advanced auto and put it in the top of my lid to act like a prefilter.

[Foxhound013]

So I bought a lawn mower filter and cut a hole in my lid and fitted it down in there to filter the air but still get more air flow. It works pretty well and now I've got a 160 in it and it runs great. d3ktrix I'll try to get pics up for ya soon. Haven't had a chance to between working on the bike and everything else around the house lol