05 jetting question 250/300 difference

[hoodlatch]

Hi all. After a 10 year bike free hiatus, I picked up an 05 ec250. It runs terrible (and won't idle for a second), until about 3/4 throttle or better. It won't clean out and is blubbery with splooge galore.

I was a bit surprised to see the jets so much higher than my old 300s.

They may not have been spot on, but ran pretty clean from idle all the way to the top. Minimal splooge, no fouling, decent plug checks, most importantly, no issues.

My examples:
01 300- LTR needle 2nd clip, 40 pj, 178mj
03 300- N1ED needle 2nd clip, 38pj, 175mj

My 05 250 CCK needle 1st clip, 45pj, 180mj

1st question is is normal to run a 250 richer?(I can understand the main higher)

2nd question is the CCK a workable needle?

I'm in the process of the 11 conversion, setting the floats, and dropping pilot to a 40 or so.
I read the jetting database until it hurt... Thanks for any tips.

 

[Jakobi]

Its not that the engine needs more fuel, but.. the smaller capacity pumps less air through the carb, which results in less fuel being picked up for a given sized jet. Completely normal for a smaller engine to require larger jets to achieve the same end result.

Given that the needle (and clip position) covers the largest range of throttle input thats where I would be starting. Given you're in top clip position already, and its blubbering away, I'd say that needle isn't the best choice and not very workable.

Also, given the age of the bike, consider checking main seals, reed petals, etc. You can jet all day long but it won't fix mechanical issues.

 

[hoodlatch]

Thanks for the input. I've looked for a ddk needle with no luck.

The bike has a fresh top end. Drained oil and coolant looked good. Reeds look brand new. I've unplugged all electrical connections, cleaned and dielectric greased.

All other things considered, same pipe & silencer, powervalve covers, even same premix. Motul 800 @ 40:1

And I guess I should add:
Western PA
1000-1500 ft
45-85 f degrees