So my 2013 klx250s has 13000 KM, got fmf pc4 + megabomb + stage 2 dynojet kit with no air box lid it. It ran perfect last year when I parked it, this year i did an oil change with the normal oil i've been using every 1000 KM with k&n oil filter, 1.5L like always, cleaned my UNI air filter, like always, but this time it's running, bad i guess. It started up great with new gas, but the oil turned black right away (drained oil for 45 min, and hit starter to poor the rest of the old oil, cleaned the oil filter place) and the exhaust smokes like crazy and after warm up and you shut it off it smells like burning oil. It's still doing this after a good 10km+ ride.. fresh new gas drained gas tank and carb ..

no idea what could be going on? any help would be appreciated thanks

 

Did you warm up the oil before you drained it ?

 

Did you over oil the air filter?

 

I actually forgot to oil the filter. I rarely even do it :$ and yes i warmed up the engine (idled lik45-10 minutes but NO riding) then drained. As an update, i decided to redrain the oil and change filter and this time used Castrol full synthetic 5w-30 and the colour is fine but still smokes a lot more than it should

 

If it is smoking still I would look at the smog system, if it is there. If it messes up sometimes it puts pressure in the crankcase, on the car systems. I can't find mine to look at it!

 

I have no clue what the smog stuff is, i bought the bike new and never took it off so it should be there.

 

Clarify the part where..."drained oil for 45 min, and hit starter to poor the rest of the old oil". Wasn't quite sure what that meant. Since the bike sat over the winter, I'd suspect the "running bad" due to fuel residue in the carb from sitting regardless of draining and fresh gas. The dark oil and smoking?...odd. I have seen on one of my KLR's with a Kehin carb where the bike sat with the fuel on...manual petcock...and the carb's needle and seat stuck open. The crankcase filled with gas, turning the oil black, and causing white smoke upon restart and running.

 

Could be right on that, I drained the carb the usual way with the bolt, then put fresh gas in the gas put the choke on and turned the petcock to ON but this time it took a bit more to start it. It would go start up till 500 RPM then die over and over again for like 1 minute then start up and idle fine. Could that be the issue gas in the crankcase? I didn't smell the oil when I re-drained it the second time. And by hitting the starter I meant like, after the oil is fully drained by itself, my Kawi dealer told me to hit the starter a few times with the plug off obviously and it would drain the remainder of the oil left in squirts.

Thanks again for the help guys.

 

Interesting recommendation on the cranking of the engine a little bit to drain the rest of the oil. I've never heard of it, and I wouldn't recommend it. The top end cam bearing surfaces are extremely sensitive to oil starvation, and even though the engine isn't actually running, what tiny bit of oil you might get out by cranking the engine, it's just not worth it...especially at 1000K intervals like you're doing. It's your call, but I think you're throwing away a lot of good oil at 1000K intervals.

 

Yeah, plain bearing surfaces require the film of oil to prevent the start of seizure.

That little bit of oil would not hurt a thing. Considering I spent 20 years in/around a bike shop and hung out too much (according to my employer) in service, I never ever saw an actual oil failure. Only lack-of-oil failure. It's when it ain't in there that's really bad! We had one customer who stripped out the oil drain plug on their ATC200 so they welded it up, then added oil when needed. It half wouldn't surprise me if they were still running it.