Old gas and power loss?

[EcEvan03]

So i just bought an 03 ec300 that was bought new in 05. Very low miles, still has original tires on it. When i got it home i took it for a test ride and raced my friend with a 04 ktm 200exc and i expected to beat him pretty bad but we were neck and neck the whole way the guy i bought the bike from said the gas was old. Im thinking from last summer, could this cause a ~10 hp loss? And account for the lack of power? I drained the gas and put fresh gas in and it starts easier and sounds better but havent gotten to ride it due to rain.

It also still has stock jetting, i know these bikes are jetted poorly from the factory. Could this be the problem? Runs rich.

Should i clean the carb or powervalve? Any insight would be appreciated!

 

[desertgasser300]

I would pull the carb off and give it a really good cleaning. Old gas will turn into a shiny stinky varnish that will coat and plug small orifices in the carb. Put a new plug in and check your jetting.

 

[EcEvan03]

Ok will do. Also what should the float be set at i read they are too high from the factory?

Anything else i should keep an eye out for or do with this model and year to ensure its longevity and proper functioning? Thanks again.

 

[EcEvan03]

Also anyone have any jetting advice? I read 178 main 42 pilot. Im at about 500ft elevation.

 

[stainlesscycle]

jetting will be dependent on needle more than anything else. what needle is in there?

float height should be 16mm.

you'll know it's jetted correct if when you wack the throttle the bars hit your face

on a straightaway the ktm200 should run with it for about 150 ft, then the 300 should just destroy it.

 

[EcEvan03]

Its the stock needle. Would i be better off with an aftermarket one and jetting accordingly?

It pulls wheelies everytime i shift pretty easily but semms not to have the top end. But maybe it should wheelie even easier.

I ride year round would a new needle allow me to adjust for wide temp range?

 

[Rick]

Could be a power valve sticking as well. Do a search on power valve cleaning....plentyof info on that subject.

 

[stainlesscycle]

what is the stock needle in there? and what is your jetting now?

 

[EcEvan03]

Stock need n1eg 38 pilot not sure about the main yet. Im going to get a 42 pilot and 178 main put stock needle 2 clips down from the top and see how that goes. If it doesnt work ill try a n3eg needle or cek. From what ive read that should clear up my issues and give me the power im missing.

Any thoughts?

 

[Clay]

Its the stock needle. Would i be better off with an aftermarket one and jetting accordingly?

It pulls wheelies everytime i shift pretty easily but semms not to have the top end. But maybe it should wheelie even easier.

I ride year round would a new needle allow me to adjust for wide temp range?

What gearing is on the bike?

 

[stainlesscycle]

i don't know your elevation/temperature/slide. but i put these numbers is:

cek, 45, 178, #3 on the needle. that's almost identical to what i have (ddk/45/175/#2clip) with the cek leaving just a little lean dip of 5% at 1/2 throttle. you can get a little more top end leaning the main - i've found i don't really use the overrev on the 300 like i did on the 200.. just never get into long straights where i run outta gears...

if you're 500-1000ft and 70 degrees, that should get you really close. it may just need a slight needle position change.

i can't plug in n1eg / n3eg into jd jetting guide. can't remember how to put in n1/n3 #'s...



if you're geared 13/52 it will wheelie at every shift point. i went to 13/50 and that made it much nicer.

 

[EcEvan03]

Stock front (13)? And 51 in the back. Stock exhaust ltr power valve cover.

 

[EcEvan03]

Ok im in maryland so my numbers will be close to yours. And the ones i was thinking are.

It does wheelie at every shift but just seems to be lacking mid to top range. I tried adjusting the air screw yesterday to see if i could improve it just a little bit but ended up fouling my plug because i turned it in and started at 1.5 turns out so i knew where i was. I guess it was more than that before and was right on the edge of being too rich.

Ill rejet and adjust my stock needle before buying a new one as well as check my powervalve. Thanks for all the help.

 

[EcEvan03]

Ok got the power back, at least some of it. 178 main 42 pilot 2nd clip down stock needle. But its not trying to idle, i have idle screw all the way in and air screw 2-2.5 turns out and it barely holds a high idle. Should i go leaner on the pilot? Oh and took off pipe guard and found out i have a fmf fatty pipe if that makes a difference. Spark plug is still black and oily after rifmding.

 

[stainlesscycle]

i can't run numbers on n3eg, so i have no idea where you're at... i don't know the specs on n3eg

if you can find a ddk/cck/cek somewhere at least you'll be where most people are...


many idle issues are needle diameter, slide, and float height. not necessarily pilot size. you can overcompensate by leaning the pilot, and you may have problems.................

also, back the idle screw way out. all the way in you're bypassing your pilot circuit... does air screw have any noticeable effect?

 

[EcEvan03]

Air screw in idle drops and stalls. So would going down another clip not help because of the taper? If so ill just get a new one. Id like a needle thats not too agressive something smooth and torquey

 

[stainlesscycle]

Air screw in idle drops and stalls. So would going down another clip not help because of the taper? If so ill just get a new one. Id like a needle thats not too agressive something smooth and torquey

once the airscrew is out 1/2 turn or so, does any amount of turning out make the engine race? if not most like the idle is in too far and you're bypassing the pilot circuit. or float level is wrong and fuel is bypassing pilot.

i don't know the info on the n3eg so i can't even guess....i would assume it's 2.715mm diameter so it should idle... but i don't know taper etc.