Jetting 04 EC300

[yowie05]

Hi guys
I've been playing with things a bit since rebuild. Just wondering on thoughts on this plug. I ride mostly single track with some WOT but not much. Last ride was 52 klms and just hit reserve as we pulled up.
Pilot is 35
main 178
needle N3EG clip 2
I feel it's a bit rich low to mid as once I open it up a bit it takes a second or 2 to clean up then gas. Its still g9t heaps of power all round but I think down low it's not as good as can be.

 

[yowie05]

edited Original with pic. it look like carbon buildup on plug . I don’t get any oil leaking from end of exhaust so think it’s burning it all. Ts really dry n the end of exhaust. I run it at 50:1 maxima castor927 with premium fuel(98octane)
Any ideas

 

[(F5)]

Plug colour is irrelevant on a dirt bike. It's only a roadrace flat out tool.

That is a tiny pilot jet. I had a 42 with that needle. Can't remember position sorry.

 

[yowie05]

Yer not too concerned with colour just what looks to be the buildup on plug considering that plug is only probably 8hrs old.

 

[Gasser Nate]

I agree with F5, I was running that needle on clip #2 with a 42 pilot and a 175 main. I?d be checking your float height. Mine was miles too high before. It shouldn?t spill fuel until leaned over to at least 45 degrees.

 

[yowie05]

35 pilot is what was in it when I bought it I?ve tried 38, 40, 42 and it progressively got worse on take off and ext to no throttle. Also 35 is what the book says is standard for that model.
When bought it had 35, 178, N1EF clip 2.
Pretty sure float level is close to the sweet spot as I?ve adjusted float as per tutorial and lean bike over test. If by chance float level is low what would that cause? Or too high?
Thx for replies.

 

[memphis2857]

Crank seal


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[memphis2857]

Also what 2T oil are you using? Something with a super high flashpoint like Motul 800? That could cause the bike to load up if riding below 1/2 throttle for extended periods of time

And another thing, which carb is on it? AS1, AS2, 36mm, or 38mm? If you have a 36mm, that main jet is way too big

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[Zman]

Crank seal


I agree that you should check the clutch side crank seal. That is a large amount of carbon buildup on that plug.

 

[Davehuge]

I agree, that's a lot of carbon build up if the plug has only run 8hrs.

It would suggest it's not 2 stroke oil that's burning and creating that carbon build up, that's why Zman and Memphis2857 have suggested checking/replacing right side crank seal.

If the seal is failing it will suck gearbox oil/air into the combustion chamber.

Gearbox oil isn't designed to burn in the combustion chamber and will leave a carbon build like you've got.

Sucking air/oil through your crank seal will also play havoc with your mixture/jetting.

In my opinion it's worth checking/replacing.

 

[yowie05]

Thx guys how to check\replace the right side crank seal? Need to split the cases? Not afraid to do the work myself,pretty handy with the spanners. I?m running ATF in the tranny.
2T oil is maxima 927
AS1 38 carby

Thanks guys, food for thought.

 

[Davehuge]

No, no need to split crankcases and no need to remove engine from the frame.

It can accessed by removing water pump and right hand side engine cover/clutch cover.

 

[yowie05]

Sweet same as adjusting power valve preload tension. What?s best way to pull seal out? Tools And such needed. I?ve only ever done bottom end b4 so all seals were take out with screw driver whilst cases were split.
Thx

 

[Davehuge]

Sweet same as adjusting power valve preload tension.

Well, there's a bit more to it than that. The seal is behind the primary drive gear so you'll have to hold the clutch basket to loosen and remove the nut on the end of the crank.

I've done this job on many other 2 strokes but never on a GasGas, maybe someone else can provide more detailed info.

It's advisable to use the correct tool to hold the clutch basket, they normally look like this...

 

[Neil E.]

You can also hold the gears the old fashioned way - a piece of soft metal wedged in the teeth. Or make your own tool by riveting an inner and outer clutch plate together.

 

[yowie05]

well bit of an update on my bikes issues. after replacing both of the crank the seals, there was no change. all good must be jetting then so used every main jet from 165 to 185 and no change at all. well must be a spark issues then. recently i purchased a few bits from an 07 model 250 a guy was wrecking. he is on this forum pretty sure its Tomac, thx for the great deal. anyway i got the stator and CDI plus some other bits Vforce 3 reeds and block wich i placed on bike but made no difference, old ones were a bit bent leaving a gap so thought why not as these ones in good nick. still same issues of running ok on the 0 to half throttle when band about ti kick in then nothing, woulnt run at all on high revs/throttle. well i was planning to run the duel mapped 07 CDI so put that and the stator on as didnt want to cutwires.
well bugger me either the stator or the CDI was the issue, thing fukn rips now. heaps of power every where, so im using
NECJ clip 1
42 pilot
175 main
not sure on AS but its about
idles fine, went for a 4 hr ride this morning and its a totally different bike, no spooge running Maxima Castor 927 at 50:1
a little concered that there is no spooge coming out the pipe but there is oil coming from the power valve line, just not heaps.
Anyway thank you everyone for the help, did so much reading of this forum to try and get ideas and well its paid off.