2001 EC300 won't idle - can't get jetting right

[bexi]

Hey all,

I've previously owned 4 or 5 KTM's (250 & 300 2strokes).

I've just purchased my very first GAS GAS EC300 which is a 2001 model.

I'm in Sydney, Australia and actually used to work for the Australian importer for gas gas so I'm well aware of the quality of these things.

When i first got it home, I assumed that it hadn't been looked after all that well but it's not in bad condition either. I took it for a run and found that it would completely bog down and die at full throttle (very strange).

I took it home and pulled the carby apart and gave it a good clean. I then checked the needle clip position and was very surprised to see it in the no 1 position.
I dropped it down 2 positions and then found that it was fine up top but i'd lost very noticeable power in the mid range.
So then i went back home and put the clip in the no 2 position and it seems to run best here once the throttle is cracked and up to full throttle.
The powerband is quite harsh when it kicks it which doesn't bother me too much but seems a little bit rough.
The main problem and what is getting to me is that the bike won't idle.
The idle screw is wound all the way in and the mixture screw is 1.5 turns out although i've tried at different positions bewteen 1 and 3 turns out.
The current carby details are:
Pilot jet - 42
Main jet - 178
slide - no 7
needle type - N1EG
needle clip position - 2

Any help would be greatly appreciated

Thanks
Bexi

 

[stainlesscycle]

you shouldn't have idle screw all the way in..take carb off, inspect slide and idle screw for damage where the two meet. inspect slide for damage anywhere. reassemble. look down the bore, see if idle screw moves slide up and down. turn idle screw out until you can just see daylight under slide, then turn in idle screw 1/2 turn. make sure throttle returns properly and slide clunks down on idle screw. make sure choke assembly is working properly. check pilot jet/pilot jet passageway for blockage.. if that doesn't fix it, i would think changing pilot jet is next.. and sometimes a fresh spark plug can work wonders..

 

[bexi]

thanks for your reply stainlesscycle.

I have already done all the things you have mentioned accept for changing the spark plug.

The bike only has a br8es in it and a br8eg is recommended so i'll get the br8eg and try that first

 

[cbutler]

Have you checked the float level.My bike would not ideal and found the float off set it and all was good.
What about cracks in the rubber between carb and reed block.

 

[das]

on my 250 2001:
pilot jet 40
main jet 175
slide 7
needle n1ee
clip 2 position from the top
air screw -2

runs perfect

 

[stainlesscycle]

br8eg/es/eix all run about the same it seems.. i jet wth es, the run eix.. the eix is hard to read jetting...

your jetting is close enough that it should idle, or at at least run for a few seconds at idle and die... is the choke operating properly?

 

[gasgasman]

Check for broken reeds.

 

[bexi]

Hi stainlesscycle

It does run for a few seconds before it dies.

It'll idle for about 2 seconds then stall.

The chocke must be missing a circlip or something as it won't stay up (you have to hold it up when starting from cold) but i've checked with compressed air through choke jet to make sure that it doesn't allow air through when choke knob is down and it is operating as it should - lets air through when choke is up and and won't let air through when choke is down

 

[jiauka]

Idle problems usually comes from reed valves and float height, specially with boyesen reeds.

have fun,

j.

 

[stainlesscycle]

then it's probably not the carb. check reeds and float height as others have said... cracked/broken reeds will make it very difficult to start/idle and bog badly..

float height if out of adjustment will override your idle screw....

 

[bexi]

ok ... i have fiddled with the float height as it was set too low and was contributing to fuel running out when tapped out ... i didn't measure it, just lifted the height so maybe i lifted it too high.

Thanks guys.

I've got the forks out doing fork seals at the moment but i'll get them done this week and report back on how i go with the bike after setting float height exactly as per specs - 16mm

 

[101racing]

Check reeds and intake tact for leaks (rubber boot , gaskets etc) try another pilot 45 . maybe the 42 is pluged partially. If your at sea level a 45 might be your answer. We are at 4000 alt and a 42 is just right at 1.5 AS and 50 degrees F.

 

[woody1965]

have u changed the plug as mine was like that and it was the plug also set my airscrew at 2.5 hope this helps

 

[bexi]

thanks guys,

I bought a couple of jets today that i can fiddle with swapping in and out.
I re-adjusted float bowl last night and it seemed like i did have it set too high - I really didn't think it would affect much unless it was too low (not letting enough fuel into the float bowl) but a few people have said it ruins your idle if it's too low so i've adjusted it last night according to specs - 16mm.

I've just gotta get my fork seals done and put the pipe back on (currently getting small ding blown out) and then i can test ride again

Will let you all know how i go.

Thanks again

 

[bexi]

Hey all,

One question i forgot to ask
Is a DDK needle also known as a N427-48??

I tried to order a DDK needle today from a distributor in Saouth Australia but he didn't have one and tried telling me i should just buy a DEK needle that he had in stock and that i wouldn't notice the difference?

 

[CACTUSREID]

bexi here's another train of thought for you. does your bike have a lot of hr;s on it by now? if so,your jet needle(the tube bonded in the carb that the needle runs in) is probably worn out to an oversize. i went through this with my 01 ec 300 in about 06. i ended up having to ignore all the suggestions and jet the bike to what it would run on. i ended up with a 35 pilot jet (approx 1500 feet where i live in canada) a #9 slide which was the biggest improvement.and needles and main jet as required! i think i ended up with a kawasaki nozh needle on #3 clip and about a 172 main jet if memory serves me. the moral here is,that the gassers seem to be the same but sometimes a lot different from each other. get it idling first and then work your way up through the rpms and jet as you go. good luck mate.

 

[bexi]

Wow!!!!!!

Hey all,

I've just put my pipe back on after having ding blown out and reinstalled carby with:
Pilot Jet - 42
main jet - 178
Needle - N1EG
Clip position - 2
Temperature - 20c

With this setting (and with float height now set correctly) the bike did seem to run a bit better. It would idle for a few seconds and then stall. Power was ok but at full throttle, there was a little bit of hesitation.

I then came back to the garage to do my first needle change!
(I bought a CEK needle as CCK was not available and the only difference between the 2 is that the CEK is about 1.5mm longer in straight section)

So I installed the CEK at clip position 3 and went for another ride - just on the road as it's currently raining and havn't got time to go anywhere else.
I turned out the driveway in first gear, lifted the front wheel and went right through all the gears on the back wheel!!!!
Absolutely awesome - I can't believe how much of a difference it's made!

So my now current settings are:

Pilot Jet - 42
main jet - 178
Needle - CEK
Clip position - 3
Temperature - 20c-35c

As I said, i've only ridden up and down the road and will go for a better ride over the weekend to test it further but I'm very happy with it.

I'm thinking on the weekend i might put a 40 pilot jet in to see if it fixes the idle.

I'd like to thank everyone who has taken the time to post up their jetting settings as it's been so helpful for me to read about everyone elses experience. I'd also like to especially thank Pobit (Dave) for his huge amount of information posted on jetting. I still want to try the N3EG as Dave says it's the best so I may do that after i've used the CEK a little bit first.