ec 300 2005 won't rev high nor idle...

[hannesd]

a friend's got an ec 300 that has had nearly everything checked but still doesn't run well.
it doesn't idle, and doesn't rev past halfway.
starts fine when cold (even without chocke) but when warmed up it sounds like it's VERY rich as if chocke was on all the time, this is how i can discribe it the best.

engine has even been split and put new seals on the cranck, new (carbon) reeds.
we swapped out my carb from my ec 200 and still doesn't run well, but somewhat better since it's a bit leaner.
silencer has been removed to check if it wasn't blocked, to no avail.
PV moves as it should.
CDI has had an update from gasgasdealer.
funny thing is, that the engine runs much smoother when we open the drain hole at the bottom of the engine i guess it then runs better as it can't suck that much fuel in...
only thing left to swap are the ignition coil and static timing on the 2K3 ign.

anybody have an explanation on how it can run better without the drain bolt??

thanks for any input.

Hannes.

 

[SGM]

What are you running in the carb?

My 2005 ran piss poor, and had no idle with the stock needle (N1...something IIRC), N3EG clip #3 and a 42 pilot, 175 main jet - and it's super sweet, with a slight fourstroke burble coming from closed throttle, that I can live with.

Not loading up, snappy all the time, and rideable.

Get the jetting right, then work on the airscrew (I run mine almost 2 turns open from fully closed now).
The thing with the stock jetting is that it's super rich on bottom, and makes all lift the throttle too much with the idle scew - just to get it to idle...and you're out of the pilot circuit...

/J

 

[trialsridr]

We had one acting up like that and it turned out the needle egged out where it moves up and down in the carb . That bike wore out a carburetor before it needed a topend ! We put a new carb with the same jetting and it was back to running great .

 

[hannesd]

What are you running in the carb?

My 2005 ran piss poor, and had no idle with the stock needle (N1...something IIRC), N3EG clip #3 and a 42 pilot, 175 main jet - and it's super sweet, with a slight fourstroke burble coming from closed throttle, that I can live with.

Not loading up, snappy all the time, and rideable.

Get the jetting right, then work on the airscrew (I run mine almost 2 turns open from fully closed now).
The thing with the stock jetting is that it's super rich on bottom, and makes all lift the throttle too much with the idle scew - just to get it to idle...and you're out of the pilot circuit...


/J

MJ 172 ,PJ is 42 and needle is probably N1EG (can't get it out since the nut ontop of the slide is screwed up :-s ) and set at it's leanest
i don't think it's that, since my own 300 used to ride just ok with that needle.(with quite some blubbering but do-able)
we swapped my complete carb (from my 200) with CCL needle 180MJ and 45 PJ and syptoms were still the same.
previous owner said it ran best with a 145 MJ but that was just to disguise the problems.
somehow i don't think it's jetting related but rather a problem that makes it run rich (or so it seems as if it's rich)...

it really runs as you're constanty running choke ON :-/

 

[SGM]

All I know is that my bike ran like crap, and I put the same jetting all other GG EC300 riders over here are using, which is the N3EG with a 42 and 175/178 - and it went from stinky rich, non idling, building up POS to just about spot on.

/J

 

[trialsridr]

did you look at the seat the needle goes down into, in the carb and see if it is egg shaped ? what did you find ?

 

[bukwheat]

Before you do anything else, service the silencer/spark arrestor...if you have a good spare that has fresh packing, put it on and try it. If you don't have a spare, repack the one you have with new packing. With the drain plug out, it is relieving just enough back pressure to run smoother.

 

[bukwheat]

Any updates on this problem????

 

[pitar]

hi guys, owner of the bike here

Just replaced the needle with a brand new N3EG.
Bike still runs like crap, no powerband whatsoever.
Next step is to check the silencer and carb seat for wear...

i'll keep you guys posted !

 

[hannesd]

hi guys, owner of the bike here

Just replaced the needle with a brand new N3EG.
Bike still runs like crap, no powerband whatsoever.
Next step is to check the silencer and carb seat for wear...

i'll keep you guys posted !

all of that has just been checked ,to no avail
power valve has allso been checked for movement and seems ok.
could a faulty ignition coil make it run that crappy?
all i can say is that it sounds kinda louder then "usual" thrue the airfilter when you open up throttle...

 

[pitar]

Carb seat checked, seems nice and round.
Needle is at highest clip (leanest).
Cracked open the silencer and nothing appeared to be broken or bent.
While I was at it a also checked that the power valve works.
The valve opened and closed nicely.
Set the plug gap to 0,8mm and checked for a good and solid spark.
Everything seems to be in perfect working order.
With the ignition cover off i also changed the timing to have a bit less pre-ignition.

Bike still runs like sh**, revs high but sounds like it's on full choke.
It's the same sound and feeling you get when you let a cold started 2 stroke idle to long on choke and try to rev it high when you drive off.
With a good running bike it would smoke and stutter a lot, but eventually ,after 50meters or so, would get it's powerband and rev through the gears.

With this bike it just doesn't get to that powerband stage.
If you ride the bike the power delivery is extremely linear.
No peaks, no powerband, like a turboless diesel engine.

Any more ideas ?

 

[Anders]

Did you check the ground connection of the ignition coil? I had a similar problem on my 06 200. I tried all kinds of jetting changes. Found that my son's 08 300 ignition stator made it run as it should. Bought an Electrex stator, but that didn't help. Bought a complete OEM stator and flywheel (could not buy only stator). That helped for a while, but before long it was back to running poorly. Removed the coil, filed down the frame tabs to bare metal, renewed both coil screws and snap-in nuts. Replaced the plug cap. After that, it has run just fine for a year.

Sent from my OMNIA7 using Board Express

 

[Neil E.]

engine has even been split

There is one other thing you should check. Find out if the piston is in backwards. If the piston has printing or etching on the top you might see it looking through the plug hole with a borescope.

 

[Eric]

Just thinking out loud...
Does it have a black expansion chamber or a chrome one?
If its the black one it has a catalatic converter in it and the bike will run like crap.

 

[pitar]

Just thinking out loud...
Does it have a black expansion chamber or a chrome one?
If its the black one it has a catalatic converter in it and the bike will run like crap.

it has a chromed expansion chamber.
next item on the list is to check the ignition coil grounds.
if that doesn't help i'll take the cylinder head off to have a look at the piston.

 

[pitar]

i removed the igntion coil, rubbed the grounds with sandpaper until bare metal and reinstalled everything with some copper grease between it.
Removed the seat, gas tank and spark plug. With a torch I was able to see the little arrow on the piston pointing towards the exhaust. So the piston is installed in the correct way.
While i was at it I did a compression test. I've got a reading of 11bar (160psi) which seems alright i guess.
I replaced the spark plug and went out for a ride.
After riding i took the spark plug out and it looked wet and black.

Probably worth noting that when the bike is warmed up you can drive it at WOT in every gear without it running poorly. By that i mean that it will rev high and won't hesitate or stutter on a constant high rpm, so it's driveable but far from normal. It still has absolutely no power. It's even impossible to pop a wheelie in 1st gear. The power delivery is the same as a mopped

Would it be possible to check the crank seals by spraying some brake cleaner fluid on them while the bike is running ?

 

[timlh]

I had a similar problem with my 01 XC300. It turned out that although the power valve was opening and closing when I checked it. It was actually working backwards. It was right after I did a total top and bottom end build. Make sure that the power valve is in the most CLOSED position when the bike isn't running. Also maybe someone else can chime in here I think if you manually open the power valve there is a chance you can drop the ball bearings out of the mechanizism that opens the valve as the RPM's increase.

Please Note I Edited my post I mistakenly made a HUGE error original read "Make sure that the power valve is fully open when the bike isn't running." I corrected the same it now reads correctly. "Make sure that the power valve is in the most position CLOSED when the bike isn't running".

Read Glens, Post below he has the best method for checking it.

My sincere apologies for posting an incorrect Post. I thought I re-read it before posting to make sure it was correct however I didn't do a Good job at all.

 

[Jakobi]

You can cycle the PV while installed. Just make sure that the actuator arm is disconnected. Pulling up on this may dislodge the ball bearings from the governor.

 

[pitar]

I had a similar problem with my 01 XC300. It turned out that although the power valve was opening and closing when I checked it. It was actually working backwards. It was right after I did a total top and bottom end build. Make sure that the power valve is fully open when the bike isn't running. Also maybe someone else can chime in here I think if you manually open the power valve there is a chance you can drop the ball bearings out of the mechanizism that opens the valve as the RPM's increase.

Ok you might be on to something here.
The powervalve is completely closed when the bike is not running.
I'll check it ASAP !

 

[GMP]

Noo.. It should be completely CLOSED when not running. You checked manual function by moving it by hand(disconnected) correct? This only verifies nothing is binding or sticking up top. You need to run the bike to check the governer function. Leave the right side cover off and replace the pipe. Run the bike, the actuator should stay on or very close to the stop bolt at idle, and move through its range quickly as revs increase until hitting the fully open position. If not, there is a problem with the governer or linkage. First and easy check is make sure that the link rod does not contact the edge of the hole in the primary cover, jamming it.