Just put on my full yoshi comp and rejetted (which was easy). Can see noticeable low and mid range gains but no 15 hp gain. I would say an increase of 5-10 hp is more accurate. I used 146/148 dynojets with their needle with k&n filter. Removed the snorkle and cut (2) 1 1/2" holes in the lid (just for the heck of it to see if there was any difference). I first ran the raptor with no holes in the lid and then with the holes to compare. Couldnt really feel any difference. I plan on removing the lid in the spring and jetting up with mikunis. How does this info compare to gains from everyone else's yoshis'? Oh and it sounds freaking AWESOME! No hesitation or popping or any of the sort, do i still need to do a plug check?

 

With your airfilter in place you can drill a holt at the top of the filter through the filter housing and airbox and put a bolt in it saves you from buying a Pro Flow kit Then you can launch the lid. I had the W/B full system and then went to the Yoshi and Way more mid to top increase.
Remember you can't use the Dyno jet kit with the mikunis use one or the other the Dynojet has a deeper taper for the needle and will not fit right with the mikunies mains
hope this helps
Pat

 

thanks pat

 

I have a buddy that has a cannondale which has blaze mapping and slip on pipe. In comparison, I would say there isnt that much difference. It will be interesting to see. The sound of the pipe makes the raptor sound fast, that sound may lead people to believe its way faster. As for me, I just cant see any real awesome gains (Unless i do when I take the lid off)

 

23 when I have had other bikes the difference between climbing a steep hill and not was the lid. When first trying a steep hill climb with my piped 400EX I came close to climbing it but not quite there. During the week I removed the lid and added fatter jetting and then tried and climbed it pretty easy so there is a noticeable difference with the two I think. With my raptor I had one pipe with the lid on and switched to a different pipe and remove the lid at the same time and got a huge difference but It was a different pipe also. I would launch the lid and up the jetting if it were me
hope this helps
Pat

 

removing the lid makes a huge difference......

 

Put in your 148/150 dyno jets. Take the lid off and drill at least two holes three if possible through the flange on the filter and the filter box and put bolts on there to hold the filter in place. You'll get even better results with no lid. Not 15 ponies but better than you have now.

 

I am running 148/150 Dynojets with mine, with the K&N pro flow with no lid, works great, I love it!

 

I run 146/148 and it runs great and passes the plug test

why would you change the pilots?
I see that a lot of people do that?

 

With the increase in flow with a pipe you have to up your pilots depending on your altitude. It really help build bottom end!