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Jetting change for Fmf exhaust/Recluse Core Exp setup...

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I have a 09 yz450 and its got the Mega bomb pipe with 4.1 silencer..I also installed a Rekluse Core Exp..The prob I'm having is the bike stalls on me, usually in middle of corner(mx ) when I'm going from on brakes to accelerating..It'll just die!Thought the recluse was supposed to prevent this?I also read the jetting on 09 yz450 has to be spot on for recluse to work right??Then there's the exhaust,I called FMF to get recommended jet changes..They didn't have specs on 09yzfor 450 for some reason..And it does have the famous glowing red pipe at idle,lol..Also have adjustable fuel screw,usually ends up about 2.5 turns out to run right..Air filter is backfire coated for gutted screen..All jetting is stock and I live in San Antonio at 699 ft elevation..I ride Gran Prixs and mx. Also installed Boyeson supercooled pump..Another thing it does is ill adjust idle up to go with my setting on recluse engagement(blue springs),and when ,wI rev it up it stays idled high for a minute and then slowly idles back down..Only way to fix that is turn idle down which prevents me from setting idle high for clutch..Leak somewhere causing lean condition??Any help with this setup would be awesome!!Do I need a jd jetting kit??Thanks in advance...

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2.5 turns out means you are lean somewhere. Probably an air leak in your new exahust. That would explain the 'hanging-idle' symptoms too.

Do a 'spray' test with spray brake cleaner on all exhaust and intake junctions.

Other sources of leanness/hanging idle:

- Stuck or over tightened hot start

- corroded hot start

- dry throttle cables

- push cable too loose

- missing o-ring on the fuel screw

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Ill check those..when I pulled out fuel screw awhile back(cleaned Carb),when I did the spring and one o-ring fell out..

There IS just one o-ring right??Ive been wondering if that was it??I know on cars its the same when idle does that there's a vacuum leak somewhere causing lean condition..Ill check all of that thanks...I know we tried 2 size bigger than stock piot jet and it got worse..

so we went back to stock..

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Ok,heres an update..I rejetted to 165 main(from 160),changed pilot to a 48(from45) and moved clip on needle tom the 4th notch(from 3rd)..I also found that the msr fuel screw had washer first then the o-ring then spring(surely caused issues).Then i replaced engaement springs to high setting on rekluse,installed all blue springs,,Havent rode it yet<BUT>,now when i start it,the pipe doesnt glow as bright red,now its barely noticeable and the thing starts on first kick(never done that before)..Also,the fuel screw adjustment ends up at about 1.5 turns out(without riding it)..Also adjusted throttle cable to 1/4 in of slack and NO hang idle now..So what do ya think about fuel screw ending up at 1.5 turns out??? Overall i think it has helped,will see soon..Any opinions?

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You are golden. You are going to FREAK at how much better it runs and how the clutch engages.

Man I hope so! Of course its a 450,I don't know if I can handle much more?Any,ya ill get use to it!Let me tell ya,I could tell a sufferance as soon as I cranked it,WAY more response and deeper sounding..it started first kick without choke..?That was ooffdd?Can't ride it till next days off,well see!?

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***UPDATE***

Finally got to go ride the thing and it ran real good,i did notice a differance in how it pulls all the way through the power range..Once i rode it,adjusted the fuel screw and it only ended up about an 1/8 turn out to where it ran clean..SO that tells me pilot is too big as it also would not kill bike when ran all the way in..Today i changed pilot back to a 45,i did notice the pipe gets red hot WAY faster with the 45..The 48 still made pipe glow but just not as bright and as quick..(they aint made to set and idle anyways) Throttle response seems alot snappier.. I didnt stall the bike once,and i tried too..By wrecking and stopping while on throttle..Think the clutch engagement spring change and bigger main jet actually was a good choice..Dont be afraid to weigh in!?

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***UPDATE***

Finally got to go ride the thing and it ran real good,i did notice a differance in how it pulls all the way through the power range..Once i rode it,adjusted the fuel screw and it only ended up about an 1/8 turn out to where it ran clean..SO that tells me pilot is too big as it also would not kill bike when ran all the way in..Today i changed pilot back to a 45,i did notice the pipe gets red hot WAY faster with the 45..The 48 still made pipe glow but just not as bright and as quick..(they aint made to set and idle anyways) Throttle response seems alot snappier.. I didnt stall the bike once,and i tried too..By wrecking and stopping while on throttle..Think the clutch engagement spring change and bigger main jet actually was a good choice..Dont be afraid to weigh in!?

When deciding on the size of PJ, drop the idle speed until the bike is at the lowest clean tickover speed before adjusting the mixture screw.

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