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400exrider36
04-13-2012, 10:54 AM
I did some searches but just wanted to post this anyway..

I just upgraded my ex with a 440 kit, 10.8:1 piston, stage 2 hotcam, removed carb choke, airbox lid removed, and performance exhaust (actually just the stock hollowed with a core and packing).
What would be a good jetting config to start with?
I believe I have a 42 pilot from when I took the choke out last year and I went up 2 on the main...

Im also having issues since the rebuild. It starts right up when it is cold but once it warms up it won't start back up unless I push start it. Sometimes I get lucky and it just barely starts. Is this the jetting or my valve adjustments? I adjusted them to .005 and .006 like reccomended..

TheAwesomehonda
04-13-2012, 04:38 PM
Where about in wisconsin man? I live in door county. As for your questions with those mods you may want a 190 main and the 42 pilot should be good. When you try to start it warm will it turn over with the starter? Your valve adjustment should be correct.

400exrider36
04-13-2012, 04:45 PM
Yeah it turns over like normal it just won't fire...

I'm up by superior.

TheAwesomehonda
04-13-2012, 04:50 PM
I see man. So i don't know what to tell you other then go to a 190 main and check your spark plug.. Someone else should have a better answer for you.

400exrider36
04-13-2012, 04:54 PM
I just found another post with an email from hotcams saying stage 2 should be .20 and .25 mm(.008 and .01 in) Idn who to believe... I think I'm just going to back them off just a tad to see of it helps any. If not ill assume it's not the valves.. I'll also check the plug color to see how the jetting is. As far as I can tell its ok since it's running great. No backfiring on decel or anything but we'll see..

TheAwesomehonda
04-13-2012, 05:02 PM
Well this is the little sheat i got with my stage two hot cam... I'd beleave that..

400exrider36
04-13-2012, 05:05 PM
Yup same here... I did snug the shims pretty tight when I was adjusting them... Ill go gentler next time...

honda400ex2003
04-13-2012, 05:33 PM
.005" and .006" for the valves when cold as your sheet says. the least that you could go would be .004 and .005 but thats a bit tight anyway.

most likely a 180 or 182 (180 is probably going to be right on but to break it in a 182 will be fine) with your 440 and what you have done. go 3 turns out on the f/a screw, 3rd notch on the needle. maybe the 2nd if you have a bit of a mid range chug to it.

im from tomahawk, if you are ever up there, look me up and we can ride.

steve