KTM 530 missing and heavy idle smoke

Hi guys, i understand there have been smoke blowing issues before, but i am thinking mine sounds like stem seals and am looking for your opinions -

At WOT after about 10 seconds the bike begins a savage miss at high rpm (about 135 km/h ) but no smoke when revving, however if engine braking or allowed to idle for 10-15 seconds, It smokes like a steam train. Any one else thinking stem-seals or could this still be rings. Thanks in advance, Wharbio.

My 530 was smoking after a good twist session too...had the dealer check it out, ended up having to much oil in the case. Check your air box for motor oil, and keep the oil at 600cc. That's what I was told.

Hope this helps.

Yeah I second the too much oil part. My 525 was smoking like mad when I bought it new last May. I took it back to the dealer and they changed the oil and watched the level very close. It's been fine since then. As far as the miss goes, have the smog accessories been removed? How about the silencer? Is it stock? That's something a simple jetting kit (or adjustment) will fix I think. I'd do the jet kit and change your oil being careful not to overflow. If it's still smoking, take it back to the dealer you purchased it from. They'll most likely take care of you.

Ok, basically in the head the exhaust port and an oil gallery where too close causing exhaust gas to leak into the crank-case and push oil through the breather into the carb. My mechanics pulled this engine down and were shocked to find nothing visably wrong with it! After calling KTM techs who luckily had seen this before KTM has sent out a new head which unfortunatly is on back order from Austria :smirk: . Mine is 2 months out of warranty, but thankfully KTM came to the party as it is a defective part. One thing to note is that after 3000 km (HARD KM - i rev/flog the guts out of this thing) the ring gaps are still spot on, the bore/piston looks GREAT. Keep your eyes on it tho guys, if you experience smoke/missing but otherwise normal running, get it checked - and if your mech is stuck, mention this.

Ok, basically in the head the exhaust port and an oil gallery where too close causing exhaust gas to leak into the crank-case and push oil through the breather into the carb. My mechanics pulled this engine down and were shocked to find nothing visably wrong with it! After calling KTM techs who luckily had seen this before KTM has sent out a new head which unfortunatly is on back order from Austria :smirk: . Mine is 2 months out of warranty, but thankfully KTM came to the party as it is a defective part. One thing to note is that after 3000 km (HARD KM - i rev/flog the guts out of this thing) the ring gaps are still spot on, the bore/piston looks GREAT. Keep your eyes on it tho guys, if you experience smoke/missing but otherwise normal running, get it checked - and if your mech is stuck, mention this.

I'm having a similar problem, but the problem as you described it is hard to picture. I fail to see how a pressurized top end can cause oil to enter the breather hose, unless something else is going on in the top end. My brand new 530 is puking oil out the breather hose in large quantities which would cause fouling and smoke if the breather was connected to the carb, but I have seperated mine and plugged off the carb port, and have it vented to bottom of the air box, which is now soaked in oil and running out the bottom of air box.

I have not been able so far to pin point the cause of the excess oil coming out the breather however. The vent is horizontal to the valve cover and I do not remember a baffle on the inside, but then I did not pay to much attention to the shape of valve cover.

I suspect that a oil spray jet may be spraying oil right into the opening where it can run straight down the hose to carb.

I will be pulling off the valve cover to take a look soon so stay tuned. Oh, by the way my bike has never been ridden past the end of driveway, so simply idling motor has caused this puking from the valve cover vent, and also I measured the crank oil capacity and placed exactly 600ml in the motor which put it slightly above the window, but visible if tilted 20o to the side. Motor runs perfect and starts great with no smoking.

I'm having a similar problem, but the problem as you described it is hard to picture. I fail to see how a pressurized top end can cause oil to enter the breather hose, unless something else is going on in the top end. My brand new 530 is puking oil out the breather hose in large quantities which would cause fouling and smoke if the breather was connected to the carb, but I have seperated mine and plugged off the carb port, and have it vented to bottom of the air box, which is now soaked in oil and running out the bottom of air box.

I have not been able so far to pin point the cause of the excess oil coming out the breather however. The vent is horizontal to the valve cover and I do not remember a baffle on the inside, but then I did not pay to much attention to the shape of valve cover.

I suspect that a oil spray jet may be spraying oil right into the opening where it can run straight down the hose to carb.

I will be pulling off the valve cover to take a look soon so stay tuned. Oh, by the way my bike has never been ridden past the end of driveway, so simply idling motor has caused this puking from the valve cover vent, and also I measured the crank oil capacity and placed exactly 600ml in the motor which put it slightly above the window, but visible if tilted 20o to the side. Motor runs perfect and starts great with no smoking.

Latest round of testing revealed some interesting results.

  • Confirmed earlier test by idling motor and oil was indeed coming out of my breather tube which is connected to bottom of air box, and retains the T fitting with vent line coming up from the transmission.

  • Removed the breather hose from rear of valve cover and reved motor to see if oil source was from valve cover. No oil at all was coming out of the valve cover. This was quite puzzling.

  • Removed the transmission vent hose from the T and capped off the T. Idled motor again with the occassional blip and oil was bubbling out of the transmission vent hose, this seemed incredible as the oil worked its way up a 6" piece of vertical hose. I added a connecter and another piece of hose up to the backbone and restarted motor, it now managed to find its way all the way to top of hose and spewed like a mini vocano.

  • Curious whether the transmission housing was being pressurized I now added another piece of hose and placed in a container of water and ran the engine again, brief bubbling took place then seemed to be reduced to nearly no bubbles at all. It appears that the tranny is not pressurized as the bubbles stop, also the water was not sucked back up the line so there was no vaccuum being created either.

  • Next I removed the drain level indicator plug on tranny to see if the oil level and gone up of down since last time I checked, and it appeared to be at exactly the right level, maybe a few cc's low, from what had spewed out, but nothing noteworthy.

Conclusion to date. Not really sure what is going on but stay tuned for more testing and comments from KTM.

My bike came from the dealer with too much oil in it! I think this is a common mistake. Dealers and the manual say 700cc..................................TOO MUCH! Only needs 600cc.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now