I have an '05 Raptor 660 completely stock, except for a K&N Powerlid. I was wondering if anyone has played around with the jetting with this set-up. I currently have Dynojets 142-Left 144-Right and am running at 0'-3000'. I called Dynojet and they said to run 165/170. What do you think??? Thanks in advance!

 

I own an 05 raptor as well. I installed a pro design filter with the K&N filter lid. Big Gun EVO X full exhaust. I bought the Stage II Dynojet kit. I gathered as many jetting specs as I could and 150/155 was the most common setup, so I wouldn't have to keep tearing down the bike. Now I found some websites explaining the jet size differnence of the Mikuni jets vs Dynojet (Dynojet being bigger in size due to no taper of the jet orifice. Looks to be about a 10 size delta between the two). I don't know if the 150/155 is Mikuni or Dynojet. The tech sheet that came with the needles and jets recommended a 146/148 which I found at sea level to be too rich. I'm running a 144/146 Dynojet main and stock 22.5 pilot with the 3rd clip position and 3 turns out on both air screws. Big gun doesn't recommend jetting change, but the K&N power lid came with a 150/155 Mikuni jet. I have no patience to experiment with the Mikuni jets to see if they run better. As is it still may be running a bit rich on the top end but feels very good on the low end. May recommend a 12 tooth front sprocket over the stock 13. Hope this gives you some idea. I would say you could run the 165/170 with the clip in the 2nd position. There's no way you should be able to go from the 142/144 with the same clip position (I assume your on the 3rd clip now?). Hope this helps.