LC Left Side - Very Oily Exhaust

[RD4ME]

Hi Folks,

Fired my LC up today and was doing some prep for the season. I noticed the left side exhaust was very oily at the tip - did a demo video here https://youtu.be/h8gTxgtZiYs
The cylinder fires and bike runs fine - but the left exhaust is very oily and the exhaust temperature at head is about 40F-50F degrees cooler compared to the right side.

I've checked my petcock and carb N&S - they seem to be fine. I've changed the plug on the left - and it makes no difference.

Any ideas what might cause this?

Thanks.

[kpke]

That's a big difference. If the motorcycle has been "resting" for a long time, maybe there was some seepage on that side and it's blowing it out. If it is properly firing on that side, I would give it a rip on the road and see if it cleans itself out. Was it stored on the side stand for a long time?

[RD4ME]

Yes - it has been sitting for a couple of months - but on the centre stand. I pulled the fuel lines and I do see that there is a slow leak past the petcock even though it's in the off position. I changed the o-rings but it still has the slow leak. I guess the fuel must also be pushing past the needle too in order to have ended up in the exhaust. I'll have to check the floats and pressure test the needle. I did find an easy way to drain the exhaust pipe.

[silverstrom]

Or oil is leaking past the oil pump check valves and getting into the carburetor, which means into the cylinder on the affected side. It happens easier than you might think.

[RD4ME]

Thanks - yes I did check my oil tank level and it hasn't changed over the winter. I intentionally keep it at the low end in case it decides to sprout a leak and spew $20/l synthetic all over my floor!

I did notice that my once full fuel tank is down to about half full now - and the bike has not been ridden since the last top up!!!

So I'm guessing that while I might have drained some of the fuel that was sitting in my pipe, there must be a few liters that just seeped down and is now sitting in the crank case.

Anyone know if this needs to be drained - and how it can be done without removing the top end?

Thanks!

[kpke]

You have already started it so it isn't hydro locked.

Start it, warm it up, go somewhere where you can let it rip, and redline it a few times.

[RD4ME]

Thanks Ken - that sounds like a formula for a fun weekend task!!

Imagine I'll be like the old batmobile laying down an oil slick behind once I hit about 6,500rpm!

[two-stroke-brit]

With that set up all you need is a green screen and a good fan.
you could climb aboard and make an awesome wheelie video.

[tacky1]

With that set up all you need is a green screen and a good fan.
you could climb aboard and make an awesome wheelie video.

[RD4ME]

Well - I took advantage of the amazing weather and followed the advice I was given. Warmed it up and got it close to redline a few times. Probably put 15kms on it.
Brought it home and did the paper towel test and it came out clean on both exhausts - no more oily splatter. I've ordered a replacement petcock as mine leaks about 250ml each day.

The funny thing is I expect it was probably doing this all last season too! My bike ran great but was terrible on gas. I ride mainly on weekends so it was probably dropping a couple of liters of gas into the crankcase between each ride!