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Discussion Starter · #101 ·
runs well with the turn down but loud when I get on it. I'm 3 turns out on a 42 pilot right now. Tried 40 and was nearly all the way out. I do not see why I'd need a 45 pilot but who knows. My 150 main is giving me a slip bog if I mash it. I started with a 160 after lunch and worked way down to 150. I think I need right around 145/148 with using the stock amount of air flow. I have 3 (3/4 x 4inch) slits in my air box. If I use two I get intake drone like hell...cool if your on a track but Its louder then the exhaust. I'm old and do not care about all that noise. I'm still flipping between stock 400ex and this Lexx muffler. It needs a few mods to be 100% sealed on the pipe. Some area they skimped out on

I just ordered 142, 145 & 148 main. Again I am not after Nosie or Power. This was just to trail ride with my daughter. I hate that I've spend about $100 in jets, but you have no idea what's needed. Once the bog settles out, I'll play with needle. So far plug looks the color of cardboard.
 

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Discussion Starter · #102 ·
well like anything else, my bog got worse with smaller mains. I grabbed my largest one @ 180 and I think its gone....seems odd I'm that large but my air box is really breathing too. I ordered 10 more spark plugs to check ranges again. Last nights rip I will say it felt very healthy. I do have to remember this is an EX national race motor that's detuned. I never got the carb with the motor so how knows what was ran.
 

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Discussion Starter · #104 ·
i did a few more tests, than i decided to start messing with the needle clip. Well turns out 2005-2014 400exs they took all adjustability away. This is perfect...not! I ran a few runs today on a 42 slow get which is not 1 turn out and a 142 main with only 1 3rd of my air box lid open. The machine ran better on a hill in 2nd gear with no bog....
My plug looks tanish. I've kept track of my plugs and test on a shelf in the garage. Nothing about this machine has made any sense from day 1.

SO i finally had enough and ordered jets from 125-140. Ill take jetting back to what a stock 300ex was, however I am running 38mm carb.

If this does not work I will order a 99-04 400ex needle and clip. Something stupid is off. I even put new corn 93 in today. With todays fuel I wont use it if its over 4 weeks old. It turns yellow. This is one of the reasons I wanted the engine builder to tune it. I might just call him soon and tell him that his uncle failed horrible at jetting it.

I came t terms which I do not like the LEXX pipe. Its a stupid nice pipe but my sensitive ear just can not handle it. Thats on ebay forsale.
 

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Discussion Starter · #105 ·
Grabbed 2 cans of busch lite yesterday afternoon and dug into it more. I ordered a needle jet from 99-04 400ex so I could adjust the clip. I took out my 42 pilot and put in a 40. Put new exhaust gasket and band on my OEM 400ex muffler. Tapped my crazy air flowing air box middle section up and 15 mins later I am perfect. No bogs if I mash it. I will now weld a plate over the middle section of my air filter for force air on either side of the filter. One day this week I want to put a 42 pilot back in as a test so I do not need to use the choke lever. I guess my problem was I was changing exhaust out and trying different air flows on this huge flowing air box i need to make so I just was unable to get a baseline. I can stand the thing up with the flick of the clutch lever in 3rd gear. It's a fun slower machine like I wanted.

Next week I hope to play with needle positions for the hell of it. Figures I spend $40 more in jetting stuff and magicly I find the sweet spot. Sunday Ill go take it on a 20-30 mile run.
 

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Discussion Starter · #107 ·
I ended giving the machine all the air it could handle with my 3 slotted air box. 148 main and a 40 pilot at 2.5 turns out on fuel screw. It's healthy, it didn't like not moving the clips on the needle. Taking it up to the hills sunday with my daughter...I'm gonna run the shit out of the machine so it can get really warm. We will take the stuff up to chainge jets too. basicly Ill ride with with no front fenders to really get it dialed in. Thats the biggest PITA. Basicly I'd say im 95% there. I am use to EFI machine so the better I can make it the better for me. Project 95% over
 

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Discussion Starter · #108 ·
Road it 3 hours straight. Burned out all the oil in my OEM 400ex muffler. I guess it smoked from the parts machine. Seemed to run really nice for a carbed machine. Checked the plug...not white but not tan either. Bumped main up from 148 to 155. Running this weekend again. Thing seems to want fuel....baffles me but it was a race motor that I de-tuned. It's NOT fast, its's NOT powerful. It's fun if just trail riding. It's not like riding a 2 stroke that's for sure....when my daughter fits it we will have a nice space machine waiting for her. off to next build (i'm $1600 to the good and a free titled atv lol)
 

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Discussion Starter · #111 ·
155 main jet was still not enough, I bumped it to a 160. I was stupid close but felt I could cool motor a brown plug a tad more. I road it an hour again at the hills sunday again. It should be good after this run. Than it can sit awhile. I went back to 18's on it. the mudlites are just crazy heavy adding about 12lbs of extra rotating mass....I have yet to like them on any sport quad but a KFX450R...

heres is a quick vid of me tracking up a 300ft loose coal hill

 
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