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trodge400ex

2003 Honda 400ex - Help!

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i have a 2003 400ex. when i got the atv it had a 40cc big bore kit but i went back stock because it was knocking. i put a new carb with stock jets. when im riding in first gear and and shift and get on the gas the quad wants to bog. it has no low end torqe what so ever. it also has a new plug. idk if it has something to do with the valves or what. idk where else to look.

thanks.

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there are alot of guys here that have ex's and can probably steer you in the right direction. before you put it back to stock, was the low end torque there?

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A member named CK_1999 would be the best guide. He knows EXs inside and out. Also ask Cheriah she is a wiz when it comes to carb problems

Sent from my SGH-T989 using Xparent Blue Tapatalk 2

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The slow jet is a #38 is that what you have? Main is #148 but i dont think that circuit is the problem. Pilot screw is 2.25 out.

Maybe you have some dirt in the carb too.

If you have the room do a slow speed plug chop.

Sent from my SGH-T989 using Xparent Blue Tapatalk 2

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I dont think so.... 400ex should have some low end grunt. How does it pull mid to wot? Does it feel like the clutch is slipping?

Sent from my SGH-T989 using Xparent Blue Tapatalk 2

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if yu are still running the stage 2 cam you will need more fuel to get it to run properly ... i would up jet a few sizes and see how that does ... with the stock jets its going to be running lean with that cam and will also run hot and cause it to ware the rings out ..(the rings will get hot and will lose there temper and then not be as stiff and will let it lose compression and then it will start smoking ) burning oil way sooner than it should from normal riding ..i learned that the hard way when i was building and running several different motors in the same 400ex for different races and hill climbs and dirt drags ...i was always useing the same carb .. and needed a different jetting for each motor ..of wich i finally did after wareing out rings several times ..

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Thanks ck for smacking me in the head I didnt put 2 and 2 together... Factory jetting with stage 2 cam...i have to stop working 3 jobs

Sent from my SGH-T989 using Xparent Blue Tapatalk 2

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Dont worry bout the main jet that fuel circuit isnt the problem. I think the problem is the pilot circuit. The screw should be out 2.25 from light seat. Did you try that?

Sent from my SGH-T989 using Xparent Blue Tapatalk 2

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