Idle probs, can't seem tp resolve.. Help!

[RichyN]

Hi, I just bought an EC300 yesterday. Is 2007 model. I have a problem with
idle, when blipping throttle the idle stays high for a while and then drops low.
When riding is cutting out.
The slide stop screw seems a long way in. Adjusting air screw doesn't make a lot of difference unless wound right in when it stalls. (is slightly faster when right out).
I even took the screw right out and the wasn't a massive change. Blip again and its up there.
I am at ground level 20C. I have changed the pilot from the #35 fitted to a 42.
Changed the float height from 17.5 to 16 as per Keihin site. Made little difference perhaps a little worse. Also was hard to start today on choke, took a few kicks. Fresh fuel.
Stripped the carb and blown out all the passages. The throttle slide is smooth and cable has free play. carb has #7 slide 35 pilot, 16mm float height, 170 main jet Needle is M1EF clip on top groove.
I tried turning the fuel off while idling, did not change speed just cut out after a while. there is a little smoke but not much. Small amount of oil dripping from exhaust port where pipe fits, Plug is black.damp with some shiny parts not sure if relevant at idle. Piston seems to have brown, black and silver patches looking down plug hole.

Anything other than carb that you can suggest please?
As I have blown passages out I assume clear but difficult to tell, air is coming out the other end.

I am scratching my head on this.
Hope someone can advise. BTW I did read through other thrreads
and saw the info about 42/45 pilot but also 35 pilot jets so must depend on the bike.

Thanks

Richy.

[Brian VT]

Might be an air leak at one of the carb. boots (overtight?).
With the bike running spray some carb. cleaner around the joints. If the idle speed changes then it's sucking the spray in.

[rpduc]

Have you tried moving that needle clip? All jetting threads I have read most commonly suggest position #3.

The poster in the other current idle problems thread resolved it with a CCK needle.

[Eric K]

First, make sure you don't have any air leaks as noted.

Second, get a CCK needle installed in clip 3 and report back on how it works.

[RichyN]

Thanks for the advice, I have sprayed carb cleaner, no air leaks.
Seemed rich rather than week though so air leak was not expected.
Have been out today on bike seems OK with a good run, idle keeps up for short
periods when stopped. Tried needle on middle clip, runs a bit thick at 3/4 throttle.


No hesitation or anything so that's good, needs fine tuning in the middle.

Will try the other needle recommended soon.

Cheers

Rich.

[101racing]

We did the full RB Design head and carb mod on a 08 ec 300 and it is amazing how good it runs top to bottom . It is not finicky at any altitude or temp. Well worth the time ,money and trouble.

[stay_upright]

A head mod is probably OTT for an idle problem and I'd ride the bike quite a bit first to see if you want the benefits a revised head may offer (and if you want to keep the 300).

How long do the rev's stay high after blipping the throttle - it's normal to take a little time to return to idle speed but not normal to keep a high speed for a long time.

When you say it's cutting out when you're riding it what's happening? I have a few issues with my 300 in that there is slight clutch drag so the idle speed needs setting high in neutral so that it will not stall riding with the clutch pulled in. Also with the idle set if the engine is not fully upto temp the throttle needs blipping to prevent it stalling even in neutral. Check you don't have too much clutch drag.

How many kicks did it take to start - again I can't guarantee I can start my bike first kick even when fully warm and in gear with the clutch pulled it's harder as well - I think it is te short kickstart and big capacity working against each other.

If you move the fuel screw in and it's worse you've richened it up so perhaps you are a bit too rich anyway. If you've got the time trying different fuel screw settings with the 35 pilot would be worth doing, it sounds as if maybe your pilot is too big (even though a 42 sounds some-where near) and the air screw looses effectiveness once it is more than 2-1/2 turns out then you need a smaller pilot for it to be effective again.

[iancp5]

Originally Posted by RichyN

Hi, I just bought an EC300 yesterday. Is 2007 model. I have a problem with
idle, when blipping throttle the idle stays high for a while and then drops low.
When riding is cutting out.
The slide stop screw seems a long way in. Adjusting air screw doesn't make a lot of difference unless wound right in when it stalls. (is slightly faster when right out).
I even took the screw right out and the wasn't a massive change. Blip again and its up there.
I am at ground level 20C. I have changed the pilot from the #35 fitted to a 42.
Changed the float height from 17.5 to 16 as per Keihin site. Made little difference perhaps a little worse. Also was hard to start today on choke, took a few kicks. Fresh fuel.
Stripped the carb and blown out all the passages. The throttle slide is smooth and cable has free play. carb has #7 slide 35 pilot, 16mm float height, 170 main jet Needle is M1EF clip on top groove.
I tried turning the fuel off while idling, did not change speed just cut out after a while. there is a little smoke but not much. Small amount of oil dripping from exhaust port where pipe fits, Plug is black.damp with some shiny parts not sure if relevant at idle. Piston seems to have brown, black and silver patches looking down plug hole.

Anything other than carb that you can suggest please?
As I have blown passages out I assume clear but difficult to tell, air is coming out the other end.

I am scratching my head on this.
Hope someone can advise. BTW I did read through other thrreads
and saw the info about 42/45 pilot but also 35 pilot jets so must depend on the bike.

Thanks

Richy.

That jetting doesn't look right which is making a notorious GG problem even worse. But .... I had an 03 model. Check with Dave at BikeTech if 07 is same. But it sounds way too lean for earlier models. Don't think the engine has changed that radically.

I wouldn't go below #38 pilot. Maybe 40 - 42 in winter.
The needle is probably an N1EF and I think you need a richer main of 178 or 180. Then try the N1EF on 2 or 3 clip. Even better a CCK needle try on 3. On mine the CCK was definitely the dog's.

The GG's are quite sensitive to float height. I used to set mine more by trial and error as I couldn't get it right measuring. I did find that if you had the fuel level too high you end up compensating by leaning the jetting too much but if you're not careful you'll seize it on large throttle openings. If you have it too low it'll run out of fuel in the bowl at wide open.

Once you get the carburation right you'll get an idle that is acceptable but not great. From people's experiences on here the RB carb mod and setting squish spot on helps sort it. But ... you can get it livable without that.

[ferguscawley]

I agree with Ian.

A 170 main jet is way too lean at sea level and 20C degree ambient temp.

Put a 178 main in it, N1EF on clip 2 and a 42 pilot. Number 7 slide is standard.

If you can get a CCK needle then go for it. Works even better in my 300 on clip 2 . Clip 3 was far too blubbery (rich) for my liking. Power is much more progressive with the CCK needle (versus the N1EF).

You should be able to set your idle with idle screw and fuel screw quite easily with that set-up.

[widebear]

Originally Posted by 101racing

We did the full RB Design head and carb mod on a 08 ec 300 and it is amazing how good it runs top to bottom . It is not finicky at any altitude or temp. Well worth the time ,money and trouble.

Exept he wont ship to Canada let alone the U.K., and wont deal in any other currency exept cash.