Running rich EC300
 

Hi,
Just bought a 07 EC300 and as I have little experience of this kind of engines (only old ones without reed and pipe) I have to get some help where to start out in this matter.

My feeling is that it's running rich, idle is a bit hard to set as it has a tendency to stay on high rpm and needs quite some time to settle down if it ever settles.

It sounds rich and rough when there is no load on the engine at lower rpm's, but loading it slightly makes it run "clean" (this is off the pipe).

After running on low to mid rpm's (off the pipe) it will stumble when accelerating just before getting into the powerband if I flip the throttle a couple of times it cleans out and hits the pipe in a good way with full power as I belive :-)

I need some hints where to start to look for this problem (well now if it is a problem or if I just ride it too soft lol) like carb, PV or reed, I have to add that it's running on a 40 gear (it was set up for street use when I bought it and will change to 48) in the rear but not sure at front maybe 14??

Please any suggestions will be welcome.

Lars

You may want to try opening the idle mixture screw to lean it out slightly (1/4 to 1/2 turn and see if that helps.

Thank you Zman for your fast response I will try that today and post the response.

Meanwhile I'm open to more tips if this won't do it!

Lars

You need the right needle before anything will be worth adjusting. Heaps of threads here to search and read for your year.

Yes I know the needle is very important but have no clue of what is a good one?
Can anyone just give a number for e good choise, Before I tear down the carb.

I turned the idle screw out 1/2 turn, a lot better now but migth need to lean it a bit more. It's now 2 turns out will try a 1/4 more tomorrow. Lets assume 2 1/4 to 2 1/2 is optimal is this a sign of reducing the idle jet and if so by how many steps.
Amazing how such a small adjustment can change things around :-)
I felt a new smell from the engine now, a bit leaner higher exhaust temp so I Think the smell came frome a hotter pipe :-)
Before I hade to force it to hook the pipe but now it kind of drags itself into it, as Im not used to such Power (Before Montesa 260 trial 1989 15,5 HP) well it's scary in an awesome way :-)

i am not expert but look at your needle first ,, you might be able to move it up 1 notch before changing it ,,, also dont forget its better to be richer than leaner (easier on engine)
cheer

Look i don't mean to be rude but this has been covered again and again. My 07 uses a N3 something needle (didn't write it down) but there's even a sticky of jetting database.
Try a suggested needle and experiment from there. With the std N1EF (or G) it will never run properly at low throttle no matter
what else you change. I promise. There's heaps of good info here but you'll have to dig a little.

Well I have to apologies for starting up a new "OLD" thread but I'm new here and searched in FAQ, but now I use the correct Search "link" and found a lot :)
Anyhow I'm very pleased to still get some good advices in this forum :)
There is not much on GASGAS here in Sweden so I really enjoy being around here, tons of relevant info.
My English isn't the best but you guys still seem to understand my Q's :D
At the moment I'm quite happy with the engine performance, only thing is it needs a really powerful hit on the kick to start.
Will take of the carb and check jetting, needle and its position and work from there if needed, yes also float level!
Thanks a lot for helping me out :)
Hope to stay with gasgas even though I should be a Husqvarna rider :D :D

This is what I've been running for the last two years in my 06 EC 300.

Needle: N3CG in the middle position.
Pilot: 42
Main: 178
Airscrew: 2.5 turns out.

That needle is from Yamaha. You can order them from a Yamaha dealer or online. They were optional in YZ-250's.

Yamaha part number for the needle: 4SR-14916-CG-00

I would buy a 40 and 42 pilot, the needle, and a 175, 178, and 180 main and experiment. In the hot summer a 40 and a 175 work but most the time I don't bother changing.

My elevation is 1000- 4000 ft.

Jetting questions are usually answered at "Enduro Intake/Carburetion - 2 stroke" section of the forum. Try there for more info.