2012 ec 200 jetting problems

[Simons]

Hello all. New to gas gas and 2 strokes. Just picked up a the bike last week and it has not run well from the get go. I was told to get the JD Jetting kit to improve overall performance. It did improved but it still has major issues. Here is the email I sent to JD Jetting looking for some guidance.

Hello there, (JD Jetting)

Just purchased an ec200 and was told to install your kit to improve overall performance. I'm new to two strokes and jetting and after this weekend of trying to get this thing running correctly I'm hoping I did not make a mistake.
I found it to run best (so far) with the RED needle @ 2 with the 178 main. It was running great for 10 minutes or so then started to run poorly again. The idle would rev then go down, sometimes die.
We like to ride tight difficult single track and this is where things get ugly. The bike is unpredictable in first and second gear. It loads up very quickly and I need to clear it out every 50' with clouds of blue smoke. I'll start a very short hill climb after clearing it out and it runs good for 5-10'. Then immediately starts to loose power and load up.

Here is some more info:

On down hills and choppingmthe throttle it loads up and often time dies.
When cleared out it idles smoothly (most of the time)
I do not need to choke it to start
Once warmed up and sitting on the stand the throttle has great instant response.
Start riding (putting a load on the motor) It looses its smoothness after a few minutes of riding.


The gas mileage is horrible and I've got a lot of spooge dripping out and down the exhaust pipe.
I'm running at 40:1


I've been reading a lot to learn about jetting and have come to a couple conclusions.

1. Check float level? (I did this and it's set at 16mm)
3. Pilot jet needs to be thinned? (Stock is 42)

I'd really appreciate some advice on this one. So far this has been the best handling, worst running, trail bike I have owned. Very frustrating buying a new bike that doesn't run properly.

Thanks for your time.

I have not heard back from JD yet but I thought I'd put this out there for any additional guidance/advice

[roverhybrids]

What are your temps and elevation?

What number is your slide?

Where is you airscrew adjusted(# of turns out)

I'm running a 38 pilot and I changed to a number 7 slide with the JD red 2nd from top. Sorry can't remember main size ATM.

I wouldn't say my jetting specs are great. I haven't had time to dial it in where I'd like, but the bike is very rideable

You should also check your powervalve and your squish

[Simons]

The temps are between 60-70.
My slide is a number 6
I was going to get a 38 pilot as well.
I had the air screw out 3-4 turns in an effort to lean up the 42 pilot.

Since I'm new to 2 strokes I will need to learn about squish and power valves.

Thanks for the quick reply.

[hamilton]

This is what I run in my 12 200 45 pilot 6.5 slide 172 main stock needle nozh top clip above 50f 2nd clip below 50f air screw between 1/2 -1 1/4 out tune for best off idle power. this is at sea level 40-1 mix. Install a NGK plug. This is for the carb with the black screw on cap. AS 1

[Jakobi]

Ease up turbos!

First things first.. Identify which model carb you have in your bike. Is it an AS1 with the round threaded cap and upper carb body, or the AS2 with the flat cap secured by 2 screws? They both have different float specs and jet very differently.

You are running leaner than a lot of people would on a 300.

As others suggested, what temps, elevation, other engine mods etc? Are you counting clip position from the non pointy end of the needle?

[Simons]

It's the as1 carb with the threaded cap. No engine mods. And with the needle standing vertically top is #1 and bottom is #5.

I spoke with JD Jetting today and he suggested the RED needle, #2, 175 main, air screw 1 to 1 3/4. Try it with the 42 pilot.

[hamilton]

I had a couple set up problems when new.
1- throttle cable free play not enough.
2- choke cable would apply choke when turning the bars.
3- float level was to high-fuel from overflow tube.
4- stock spark plug set me in a fit, must have been dropped.
5- jetting was very rich.
All these things are simple new bike set up prep that just need a little TLC. I spend about three full days preping my new race bikes. This has been one of the best running 200's I've owned with no engine mods. I have had zero problems after careful set up.

[Jakobi]

Originally Posted by hamilton

I had a couple set up problems when new.
1- throttle cable free play not enough.
2- choke cable would apply choke when turning the bars.
3- float level was to high-fuel from overflow tube.
4- stock spark plug set me in a fit, must have been dropped.
5- jetting was very rich.
All these things are simple new bike set up prep that just need a little TLC. I spend about three full days preping my new race bikes. This has been one of the best running 200's I've owned with no engine mods. I have had zero problems after careful set up.

+1 to all the above.

Cable choke will definitely cause the richness you're experiencing. In contrast, the AS1 generally likes richer configs than the JD Red (even in the 300s and definitely in the 250s). You'd imagine the 200 would require richer again.

I've seen the short throttle cables cause some intermittent idling issues more than once.

High fuel level/low float height definitely causes excess overflow and richness through splashing into the engine. Made worse due to the forward angle at which the carb mounts. If spec for the AS1 is 16mm I'd suggest setting it around 17.5mm

I found the stock Denso plugs don't perform as well as an NGK. Even when compared to a BR8ES (stock is EG)

[Simons]

You were absolutely correct. I had broken one of the golden rules and made some assumptions. . . . Such as the bike was assembled correctly. The throttle cable and choke were both causing problems. Explains the erratic and poor performance.
So I started over. Set the float at 17.5 mm and tried hamiltons jetting. She purred!! So I went back and started with the JD Jetting. Using the blue needle, #3, 180 main, 45 pilot. It purrs. Accelertes smooth but still rips. I'll play with it from here to maximize the power.

Thank you all for your input it was a tremendous help.

[Jakobi]

Happy riding from here on in!

Most change the bar mounted choke back to a stock keihin plunger. I think some newer bikes even had this in the spares kit.