2006 ec 300 not running as it should

eviljim

New member
I recently bought a 2006 ec 300. I had not ridden a dirt bike since giving up motocross over 20 years ago, so I do not have any thing to compare the bike to.

The guy before me had softened it a bit with an extra reed valve spacer. running it down the road there was a big bog when coming on to the pipe.
I took the spacer out, this fixed the bog but it did not feel right, did not get on the pipe very well and bogged on full throttle.

I am in the uk and the bike has
#42 slow jet
#178 main jet
CCK needle 2nd clip

I will attach the plug pic

So we dropped the clip to 1st and it seems to be running like a dream

Would like you opinion on if this is the right cause of action.

Oh am and running 40/1 moto 5 high octain fuel. Should I use standard fuel ?
 
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First things first. You want to make sure the bike is mechanically sound. Compression, rings, etc. You'll never jet out a mechanical issue. You can bandaid them to a certain extent.

The second part. Hesitating/flat power is often lean. Burbling and slow revving is rich. Perfect is instant crisp throttle response. The needle clip pos its pretty self explanatory though. It either feels right or wrong.
 
cKg9DW


trying to get the pic.
http://flic.kr/p/cKg9DW

I think it's ok now just need to ride it. I just don't want to make it too lean and bugger the engine up.

I would also like peoples opinions on the fuel. in the UK we have two regular 95 RON, supper 97 RON. I used supper the on the first one, may try standard on the next.
 
I have an06 ec300, jetted identically with CCK needle. I run mine on super unleaded at 50:1 rock oil fully synthetic.

I would think that the 40:1 you are running will make yours slightly leaner than mine?
 
cKg9DW


trying to get the pic.
http://flic.kr/p/cKg9DW

I think it's ok now just need to ride it. I just don't want to make it too lean and bugger the engine up.

I would also like peoples opinions on the fuel. in the UK we have two regular 95 RON, supper 97 RON. I used supper the on the first one, may try standard on the next.

As I said before. You will almost certainly always get signs and symptoms that the bike is running lean (especially noticable trail riding). Bike running hot, boiling easy, pinging under load, weak flat power under load, gasping and hesitating when trying to give throttle. Really lean will actually stall as you whack the throttle open hard. The exception is if you're on the borderline of lean with the main and hold it tapped out for kms on end where it can easily nip up.
 
40:1 for semi synth oil like MX5 - might require slightly richer jetting
50:1 for fully synth like MX 7 - might require slightly leaner jetting
High octaine fuel probably not necessary.

Which ignition setting ? 'Rain' setting changes the power characteristics for slippy conditions, and it will bog on WOT runs, but work well in other conditions. Keep in mind that the majority of riding in the midlands, unless you can ride like Danny Mccanney :eek: it will be rare to use more than small to medium throttle on the 300 and coming on the pipe like a motocrosser is often undesireable, causing traction loss and being tiring to hold onto.
 
CM what you doing on here? you sold your Gas Gas to some strange bald bloke, with a 1980 helmet.:D

After dropping the needle it seems, very good. Very clean though the range. I was just surprised that it was on this setting. (first clip)

In the space I had to test it I could not tell the difference in the switch mapping, so I left in on dry. and then checked the switch when I got back it seemed to work (switch close on summer), although the connection to the CID was not grate so I fixed this up a little. I may try taking the switch out and just linking the wires to test. How would yo test it's working? a strobe light I guess.

I am taking it for a decent ride on the 18th at a wor events play day so, will know more then.

Oh I have also order an new air filter (current one looks fine) so that may affect it.

J
 
CM what you doing on here? you sold your Gas Gas to some strange bald bloke, with a 1980 helmet.:D

Got another GG, but a 200 this time, and very good it is too. Test continuity on the mapping switch with a light bulb and battery. It's highly unlikely there's anything wrong with the CDI, it's unusual for CDI to fail. With the jetting you have, it should feel a little more torquey in rain setting, but won't rev through as quickly and cleanly as sun setting. Enjoy the WOR day - they're a good organisation.

As a sidenote, I think I've discovered an Achillies heel in that generation of engine case which would apply to your bike also. When I've got the parts, I'll post up some pictures on the forum of the fix I would suggest
 
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