Help with jetting

400ex killer

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Nov 8, 2016
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quad is heavily modified, running 35mm pwk airstriker. At sea level. Ran ok 50 degrees 160main 62 pilot. Never had the jetting so good to where if I snapped the throttle from a putt it would stand strait up(it should throw me off) Now it’s in the 30s /40s and it still lacks power on acceleration. I currently have a 162 main and 65 pilot and it won’t stand up when I slam the throttle. I’ve messed with the air screw with no good results. 62 pilot runs lean 65 runs rich what am I doing wrong?
 

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a 65 pilot seems way too rich to me, I run a 48 pilot in my KOR engine/34mm, I know others run 50/52. I do run a 162 main in cooler months, 155 in summer.

what does the airscrew tuning tell you it needs for the pilot ? follow this exactly to determine pilot.......
https://www.blasterforum.com/threads/adjusting-your-airscrew-pilot-jet.51060/

these keihins also require a #6 slide, and a CEL needle <(for your elevation) to run properly on these blasters, both are a MUST
 
@Awk08 yea I got the slide and needle jet, but 65 pilot was good at 3 turns out (this was judged by sound not riding) so I dropped down to a 62 and anything over 1.5 turns out rev hangs like crazy but even at 1.5 if I give it full throttle from a slow cruise it has no power for two seconds then picks up from there(this is with me riding). I’m gonna look tonight to see if they sell a in between jet. Also should mention needle and main have not been set yet. So maybe my pilot is good and I just gotta mess with the needle jet to get that punch I want? I’ll be plug chopping tomorrow at a friends house.
 
@Awk08 yea I got the slide and needle jet, but 65 pilot was good at 3 turns out (this was judged by sound not riding) so I dropped down to a 62 and anything over 1.5 turns out rev hangs like crazy but even at 1.5 if I give it full throttle from a slow cruise it has no power for two seconds then picks up from there(this is with me riding). I’m gonna look tonight to see if they sell a in between jet. Also should mention needle and main have not been set yet. So maybe my pilot is good and I just gotta mess with the needle jet to get that punch I want? I’ll be plug chopping tomorrow at a friends house.
Also should add my clip for needle is set in the middle right now(I think it’s a odd number of slots so maybe not dead center) and my back yard is literally the ocean. I think tomorrow I’ll do the plug chop for main and maybe work backwards (I know this is not the right steps but my main may be way way to rich right now so I’m gonna try to get that closer first). I do not know the compression as of now but is suppose to be 180 ish. Engine is two seasons old.
 
has this been leakdown tested ? you may be over jetting to correct an airleak.

and yes, 5 slots on the needle
 
@Awk08 yea I got the slide and needle jet, but 65 pilot was good at 3 turns out (this was judged by sound not riding) so I dropped down to a 62 and anything over 1.5 turns out rev hangs like crazy but even at 1.5 if I give it full throttle from a slow cruise it has no power for two seconds then picks up from there(this is with me riding). I’m gonna look tonight to see if they sell a in between jet. Also should mention needle and main have not been set yet. So maybe my pilot is good and I just gotta mess with the needle jet to get that punch I want? I’ll be plug chopping tomorrow at a friends house.

One cannot adjust the idle by sound or riding, the size of the pilot is determined by the position of the airscrew when setting the idle to the specifications that Awk directed you to...
 
Ok thanks for the help. I will be leakdown testing this coming weekend. Then following the process that was posted by @Awk08.