Running issues
 

Hey everyone, I am trying to sort out my 18 XC 300. Long story short I had some issues with my left and right crank seals for which I ended up blowing my top end. I replaced the piston and rings, had the cylinder inspected and was told it was still in good shape. I have some running issues with it which I suspect may just be carb related, dialing in my lectron still. I can see some light through the reed pedals so I am replacing those. I have an excessive amount of carbon build up on my piston for the low hours but all other points suggest my bike is running lean. I also tested the compression but did so without the reed block in (not sure if that will lead to inaccuracy or not) and am only seeing 115psi. See video below for how the bike sounds. I have gotten some suggestions to try but looking for all the help I can get. I love the way this bike handled and the suspension is amazing after I got it valved for me. I just want the engine to run right and have the power I need

https://youtu.be/fDLVyj2sGh8

Remember that a bike can be lean say on pilot cct, yes ok a Lectron, so lets say it can be Lean 1/8 throttle opening
Rich at 1/2
Lean again at full

Or any other combination. Just think in terms of throttle position not revs and ignore spooge products or sparkplug colour.

I hate compression testers.

Not the first time I?ve heard of lectrons and seizing/blowing up issues. I got to say I really do not know why people bother when the PWK?s are so easy to set up.
The manufacturer should have a good safe baseline for a 300 2t in my opinion.

I really second what you're saying. As said on TT the bike sounds too rich.

I still think it is a fuel flow related issue. Next time the bike shows the problem unscrew the gas cap a bit and see if the problem goes away.

The bike blew up prior to the lectron fyi.

The cap has been thoroughly eliminated. This is the second fuel cap and I removed the shorty vent hose.

I purchased the lectron out of frustration because I couldn't get the jetting right. Later found out there were other issues creating the jetting problem (crank seal) but now that I have the lectron I would like to use it. Ibam starting with removing the rk tek head and going back to stock. If I still have an issue I will go back to the Keihin. I was speaking with Rich at HoH and he had a similar issue with an RK Tek head.

I am sorry to hear you are having such problem with your GG. Good luck with the head swap.

Fair enough then, how/why did it blow up?

The piston looked like some one shot a 9mm through its top. It had just burned a hole into it...

But what was the reason? Always find out the why before trying to tune a mechanical issue. Otherwise you will be chasing your tail indefinitely.

Melted a hole in the piston. Found the left crank seal leaking after I did the rebuild

But does it still act/run lean like it did when it blew up?

No that symptom was eliminated with the replacement of the crank seals.

The video you posted on TT (after doing the rebuild) going up the hill sure looked like the bike was going lean.

Hi i have an EC 300 2018, my bike is running like your's, i tryed cleaning up the carb e checked the reed's, with no success on solving the problem.

Did you problem got away after the crank seals replacement?

How did your problem starter? Mine started all of a sudden.

Do you have to split the cases to replace the seals?

i'm realy getting desperate with this.

Thanks mate.