200 Jetting, help me sort this thing

[stainlesscycle]

Originally Posted by Rick

Stainless>>>>when you advanced the timing....did it wake up? Can did you notice a difference?

Thanks

you sure can feel the difference. it changes how the hit feels. advancing sacrifices a little bit of over rev though.

[noobi]

What does advancing the timing do to the power? give it more power low down?

[stainlesscycle]

advancing timing makes midrange hit harder, but you lose over rev a bit.
retarding timing smooths power delivery in midrange, and gives more overrev.

if ignition timing is set stock (on the 200 only...), it feels to me too trials like, too smooth.

be careful with advancing too far. if it pings you're too far.. i've pushed it to 3 or 4 degrees advanced and it didn't ping. but i'm not 100% comfortable with it that far advanced, so i set it back a bit.

if you advance it too far, it can be harder to start too...

make sure you mark where you're at now - there are no real timing marks on the 2k-2 or 2k-1 ignition.

here's how eric gorr describes it:
AFFECTS OF THE IGNITION TIMING
Here is how changes in the static ignition timing affects the power band of a Japanese dirt bike. Advancing the timing will make the power band hit harder in the mid range but fall flat on top end. Advancing the timing gives the flame front in the combustion chamber, adequate time to travel across the chamber to form a great pressure rise. The rapid pressure rise contributes to a power band's "Hit". In some cases the pressure rise can be so great that it causes an audible pinging noise from the engine. As the engine rpm increases, the pressure in the cylinder becomes so great that pumping losses occur to the piston. That is why engines with too much spark advance or too high of a compression ratio, run flat at high rpm.
Retarding the timing will make the power band smoother in the mid-range and give more top end over rev. When the spark fires closer to TDC, the pressure rise in the cylinder isn't as great. The emphasis is on gaining more degrees of retard at high rpm. This causes a shift of the heat from the cylinder to the pipe. This can prevent the piston from melting at high rpm, but the biggest benefit is how the heat affects the tuning in the pipe. When the temperature rises, the velocity of the waves in the pipe increases. At high rpm this can cause a closer synchronization between the returning compression wave and the piston speed. This effectively extends the rpm peak of the pipe.

[alkyleda]

I have a 2005 EC200 heavenly to ride I must say. I just did a new piston after approx 250 hours........I know its a long time but the bike still ran mint and pulled like a sailor. Piston was mint when she came out....just light scuffing on the front and back of the skirt. anyways I put a wossner piston in but when I pulled off the base gaskets there was a 0.5 and a 0.3 installed (bike was a spare one for a pro enduro rider). When I put it back together I put the a 0.3 and a 0.15 in. The bike goes like fury now but sucked down 10 liters of gas in 113km plus down low she burbles and farts a bit. Its got a 48p, 185m, pwk 38mm carby, running amsoil dominator 50:1,91 gas. the needle (NBHW) is second from the pointy end (I guess this is the bottom).

Any suggestions

[stainlesscycle]

Originally Posted by alkyleda

The bike goes like fury now but sucked down 10 liters of gas in 113km plus down low she burbles and farts a bit. Its got a 48p, 185m, pwk 38mm carby, running amsoil dominator 50:1,91 gas. the needle (NBHW) is second from the pointy end (I guess this is the bottom).

Any suggestions

what's your elevation? hows the plug look? both pilot and main seem rich to me.

[bchatt]

If it went well before, I'd be inclined to put the same base gasket thickness back in, or at least 2 x .3. I found on my 250 that reducing the base gaskets did improve low - mid punch but at the expense of top end overrev (and we don't want that do we - might as well by a 4 stroke!)

Also, I always run on 96/98 (depending on brand). 91 gives noticably less power.

[alkyleda]

Originally Posted by stainlesscycle

what's your elevation? hows the plug look? both pilot and main seem rich to me.

Elevation is near to sea level, within 50m, and the plug was black as the night is dark without a moon!

I have just had a little fiddle with the air screw...was 1 & a half turns out....tried it at 2 turns ...a little better but any further out makes no difference.
I am a bit of a fan of low down grunt as well as a screaming top end to get the blood pumping so I'm not so keen to change the base gaskets. I'm pretty sure standard is a 0.3 and a 0.15.

I will try lowering the needle 1 clip and see if that is better as the air screw seems to do jack diddly at the mo

Cheers for your suggestions tho...........GO the gasser

[alkyleda]

Update....... Lowered the needle 1 clip and turned air screw out to 2 turns. Its alot smoother. Lost most of the burble and farting between idle and when power band kicks in...I may drop the needle 1 more clip as it was 1 clip from the bottom to start with as there is still a little hesitation just off idle.

[gg3]

Originally Posted by noobi

Thats interesting
On a side note, does anyone have any experience with Elf 2XT, I work at a bike shop that gets it by the barrel, so it cost be around 10NZD per litre. Where as Motul 800 is 2 and a half times as expensive

Hi Noobi,Hope the recovery is going well.I used ElF 2XT in my KDX's,seemed to work fine & smells great!I took a barrel into a shop to get plated & they commented on the 'gummy' residual.That was enough to scare me off,although the mechanic was surprised as he highly rated Elf.I use Motul 800 but is getting way expensive.Interesting about the 800vs700 flash point,haven't heard that before.

[GMP]

I couldn't care less about spooge, not a variable to me. High flash point oils blow through the motor intact for the most part, as oil. If an oil burns in the motor what happens? It creates more residue. Oil has to end up somewhere in one form or another. I run Amsoil Dominator @ 36:1, which has a high flashpoint also. I can clean my exhaust port and PV parts with a rag at teardown, thats how clean it is. Just run the best oil you can, jet the bike for performance, and if it spooges so what? My plug is dark brown to black (and in the bike for months), there is some spooge running down the bottom of my silencer, my piston looks great, engine is at 190 PSI compression @ 100 hrs, and the bike runs like an animal. If you don't absolutely need a spark arrestor, run a straight silencer, as a lot more oil will just blow through. The turbine type spark arrestors are big spooge collectors, the Stealth being the worst.