EC300R '09 Jetting recomendations?

[stabak]

The bike is a euro EC300 racing 2009 model, compression is good (recent topend), clean air filter, pv looks goods etc. Was bought used thus no idea about stock specs and jets/needles/settings etc

The symptoms are increased consumption and a bog/hesitation low to middle rpm's and then it hits hard for the rest 3-4K rpm. It's not linear and crispy as it should. It needs about a sec on full throttle to rev away from middle rpm and after pulls strong as it should. Can't complain on low rpm but it's not linear This behavior exists from the first time I bought it so can't compare... About consumption, tested with my buddys gg300 06, same type of conditions and riding, he was left with almost 3lt more fuel...

Here're the settings found after cleaning the carb:
Main : 175
Pilot : 38
2 1/2 out
Needle : N1EF on #1 (top position on needle)
Sea level to 1000
68 to 95F temps most of riding

Tried to set float height by blowing with air method and find where valve closes, so I think I'm ok now... (floats mark parallel to the carbs body)

To be honest my experience is not that great with 2 strokes and don't expect my jetting to be spot on. Checked once the plug and didn't give me an indication of overly rich or lean condition.

What do you think I should do next? Diff needle?
Thanks in advance...

 

[hannesd]

check out the jetting datebase for someone in similar conditions as you and see what needle/jets they use.
most likely you'll need a different needle.

 

[stabak]

Thanks hannesd but in the jetting database, from the cck needle and through time until now appear tobe updated with lot of options what's the latest verdict?? Meaning where to start??

 

[stainlesscycle]

here's where i'm at (07 300) with a very similar needle.


8/15/2012 80 degrees, 2000 feet
1.5 out, #2 n1eg, 172, 42

very smooth, idles good, power is pretty linear.

 

[Jakobi]

There are so many variables that its hard to say what will work and what won't. I can tell you my tropical conditions (temp&elevation) are similar to yours, and I have high humidity too.

What are the fuels like? What carb is in the bike?? Has it got a shallow bowl and a flat top, or the older style deep bowl and screw cap? The later will prefer richer jetting specs. What slide is in the bike? and is it notched?

The suzuki needles and the yamaha needles both work well, but the needle diameter and clip position will have to be experimented with depending on which your bike prefers. I'd suggest maybe getting a H/W diameter to start with and tune from there.

If you provide more info as req above might be able to provide more info.

 

[stabak]

Well, the fuel is unleaded 95 or 98 oct, the carb is a PWK38, the slide #7... I'm using motul 710 (not by preference but convenience)... by your description its the older type with the screw cap, hope that helps a bit..

 

[Jakobi]

Ok, based on that I'd suggest maybe a G/H diameter. If you want a smooth delivery consider something like a suzuki NEDG/NEDH (or half clip NECx) around clip 2 and a 172 main. If you want a snapper setup consider a N3EG/N3EH (or half clip N3Cx) with a 175/178 main.

For the pilot circuit set the slide height as per image below, and the air screw at 1.5 turns out and then swap pilots until you find the one that allows the bike to idle. Then fine tune air screw for best response.

With the float heights you could consider increasing the float height 1-2mm for better economy too. (Higher float height = lower fuel level).

Then move the needle clip position to give best response from 1/4 throttle through 3/4 throttle. The main is the last circuit to dial in and is best done by feel first, and a plkug chop to confirm.

 

[stabak]

Thanks for the reply Jakobi and other folks... I'll proceed based on your recomendations and provide feedback...

cheers

 

[Jakobi]

No worries. FYI I've had no experience jetting with the older style carb on the gasser so my recommendations are based on observations of what has worked for others and older posts I read when initially starting to tinker myself. Keen to hear how you get along.

 

[stabak]

Went for a ride yesterday on a really humid day and tested a N3EG, 3 clip not touching anything else except the float height which I've increased a lot the height just for testing. (14mm)

The bog is almost gone in a way that you can't feel the transition to the pipe. Totaly acceptable and liveable... there is a very small hesitation on the 1/8 throttle which I suspect is a pilot / air matter and can be fine tuned according to Jake's propositions. Afterall it wasn't the perfect day condition wise for testing.

Consumption was way way better. Haven't felt starvation on steep parts which I guess again is ok.

Concluding I didn't expect a 8 euros needle to solve most of my problems. Fine tuning is now a pleasant procedure. It is really important to start with a good baseline (needle). Thanks again Jake & others for the help....

 

[Jakobi]

Good work. Glad to hear you had some positive progress. Amazing what difference a change in needle can make.

 

[stabak]

Just for the record my carb is the newer one not with the screw cap as i've mistakenly described earlier.

 

[Jakobi]

Ahh yeah. Moving to a W or J diameter needle will clear up that 1/8th throttle burble. You will need to pair it with a 40 or 42 pilot probably to maintain the idle and get good response still.

N3Cx is the half a clip leaner option too if you feel you want to crisp it up a tad without going a full clip leaner.