05 ec 300 stock jetting

[randy]

can anyone tell me the stock jetting on an 05 ec 300? please include all jets if you can! fixing it for a bud and pulling my hair out(wuts left)! took my 04 carb and installed it a the bike ran good(lil lean)! just woundering if the jetting is the same as 04! so if i have a starting point with stock jetting then i can go from there! oh yeah,,i cleaned the tank and new fuel line,filter,tank screen,pet cock,air filter and box and cleaned carb and blew through the jets,,before he told me that he ran some wire through the jets to clean them,,,at that point my brain stopped and i screeched,,,so thats my story,,,oh yeah,,didnt see mant gassers up in hancock,ny this weekend,,,wuts up with that,,,,gassers love to climb,(we know who we are)!!
thanks for reading and any help is good help,,thanks

[GMP]

Randy,

I'm only sure of the 250s, but don't screw with the stock jetting anyway, they run better with a single taper needle. Check out the jetting database thread. If the bike has a lot of hours the nozzle can be worn as well. I have some needles if you want to try, give me a shout.

Yeah, no problems with hills! I saw one other 250 on Sat. I'll bet next year things will be different.

[Brian]

What denotes a single taper?

[randy]

i do have the book but not very trusting of the info! its not my 300 and was looking to see if someone else changed it! the other thing is the bike dosnt even have time on it! how reliable are the crank seals? start it and it rev's to the moon! i did the carb so many times that i was suspisious of the crank seals,,already did the base gasket trick and thats fine! goin crazy,,,prob something stupid im over looking,,,hope to see more gassers next year,,some people just dont know what there missing! any more info and i will PM you glenn,,thanks!

[stainlesscycle]

revs to moon only means 2 things. air leak or choke problem. (or possibly a slide that's not returning fully)

with choke stuck open. it'll rev to moon when cold, then die.

air leak:
carb boot leak
base gasket leak
reed block leak
left side crank seal leak.
carb slide top leak

[randy]

i did pull the choke assmbly and made sure it was free,,also i did get it to idle and accept up to 1/4-3/8 throttle,,then sprayed lightly with carb cleaner around gaskets and never when up in RPM's! glenn pointed me in the direction of the needle and it seemed to work better with the needle closest to stock,,so going for stock 2mrw nite! the only thing i didnt check was L side crank seal! thanks for the input and if there is any more thought out there throw out some info! thanks again folks!!!!

[GMP]

If the seal is leaking it will hang idle. Reving high with the choke when cold is somewhat normal, mine is jetted spot on and it does this. If I had to guess I'd say that the idle speed screw is cranked in too far to compensate for a lean/rich pilot circuit. This is common. The 300s are a little more fussy to jet than the 250s and the best results have been with the single taper needles like the CCK or LTR needle, and some bikes like a #8 slide. The head mod is a big help too if you want to go that route but you should be able to get it close. I think a lot of the variables in jetting these bikes(any Keihin carb) is in the carb body casting. My KTM300 was a PIA until I cleaned up some small flashing on the nozzle.

Check the RAD valve rubber boot, they can develop small cranks after a few years. Reeds OK?

I doubt its the crank seal, they go 100s of hours on a lower end, but its an easy replacement from the outside of the case if it is.

[randy]

after asking the owner if he could remember if he re-jetted it he said no! i asked him for the extra jets that come with the bike and they were never givin to him,,,turns out that he bought this bike from dirt rider mag! it was a test bike! i did however get it back to (close) to stock jetting and it seems to have calm way down! test ride tomorrow! air screw is working it does affect engine idle when turned in or out! get it to max operating temp tomorrow and do the final adjustment! thanks for your help and insite,,probably just needed to walk away from it for a lil while!

[Trailrider]

I have had 3 Gassers, they all revved real high on choke, had to modulate cold revs with one hand on the choke turning it on and off.
Trailrider

[randy]

well thank you to helped me out with some good insite! jetting was not the issue for the revving issue when past 3/8 throttle! went to do a crank case pressure test,,,when i blocked every port and pressurized it,,it was coming out as fast as it was going in,,,,,,problem::::crank case drain plug fell out! a honda drain plug fits and it has a 17mm hex head instead if an allen wrench needed with stock! crank case plug,,huh,,,who knew!!!!! thanks again to all!