We are in WSW (Dayton) Ohio, where it is pretty frickin cold right now..... We are average about 800' AGL. It wasn't backfiring nor popping, that I can recall. I might see if my buddy will get a pair of 23's and 24's. It sounded REALLY good, honestly. Nice and RAPPY. I'm trying to recall as much info as I can.........

It could be that the 22.5 jet will be ideal on a nice hot day, but will glow red hot on a cold winter day like it was yesterday!!!

Thanks for the input!!!

 

try a 25 slow jet an 150 left main an a 152.5 right main.worked for my 660 .just right. harleypap.

 

on my kawi , when i put my yoshi on , all i did was mess with the main and i turn the air?fuel screw alittle and i was done... that was also getting ride of the air box..

 

I did the same thing on my Zuk with the Full HMF pipe. I didn't even touch the mixture screw. I went up from a 130 to a 175 main. I guess the Yamaha is different..........

 

full pipe made you jump up from 130 to a 175 ?? thats a big difference lol

 

Hili, that was on my Zuki. Not this Raptor I'm working on. The Rappy only went up from 140(L) 145(R) to 148(L) 150(R). My Zuki I gained an additional 9HP by doing the K&N filter, removed the screen in the intake, no air box lid, and the full HMF Sport system. If I go ahead and do the high comp. piston, I'm am still safe with the 175 main jet. [img]i/expressions/face-icon-small-wink.gif[/img]

 

off the subject... if you go with high compression piston and maybe some cams... look into getting a yfz or 450r carb. i got my yfz 39 for 150 of e-bay.

 

reply to off subject-------- I was thinking 400ex carb, but if the yfz 39 carb's go around 150 on flea bay, thats not a bad price at all!!! [img]i/expressions/face-icon-small-smile.gif[/img] Thanks for the heads up!!!

Back to our regularly scheduled program!!!!

 

Kawi, we also found out that the Rappy had 93 octane in the tank. My buddy and I were thinking that it might have been higher than 93 octane. I know that the higher the octane, the hotter the burn. If at all that is correct. All I do with my 400 is run the lowest grade I can find!!! It runs like a raped APE!!!!

So, I guess we are gonna try some 87 in the Rappy after we get jets on Friday from the Yamy dealer. We are getting 25's and 22.5's. We are going to try 87 and the 22.5's.

 

i think the higher octane the cooler it runs.... i run VP c-12 -- 108 oct in my kawi because i run a 13:5 - 1 piston.... running high octane gas doesnt give u more power if you dont need it. it can actually hurt the power.. and wallet. i'll try and remember and talk to my buddy... he has rebuilt all three of his craptors. i really dont know much about them.
p.s. if you run a 12:1 piston you'll probably need to run 50/50 in your bike.