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Hi all,

OK, I reported a short while ago that some blue smoke was coming out of my exhausts on start-up on a morning. A couple of guys suggested that it was condensation in the chambers, and I duly forgot about it...

Was out yesterday and came to a busy roundabout, engaged neutral, seen plod to my right, and when lights went green pulled away with less revvs than usual. It stalled Hit the start button, and a BIG puff of blue smoke came out of my exhausts! Plod looked at me, gulp! They were on red, so I scarpered anyway....

Having just read a post, that someone's diaphram was pin-holed and that caused the loss of oil and blue smoke....

I am loosing oil, having to top it up every couple of weeks. Would that be the cause of my blue smoke? Or do I need to take it too griff for a proper look over Is it just a case of taking my clutch cover off and checking the diaphram? If there is oil on the outside of it, then I have a problem I guess...

Cheers.

Be very, very sure you're not over filling the oil tank - very easy to do unless you RTFM and overfilling WILL give you buckets of blue smoke.

Excess oil will be blown into the airbox and then sucked into the motor so make sure you check the oil level with a HOT motor with the bike level immediately after you kill the engine

also check the breather hose is clear in the aiir box , just my 2p worth

Rings...A compression test tells a lot and also eliminates a lot

Hi all,

OK, will check the breather hose, defo not over-filling on the oil, it's below the max fill on the tube. As for compression test, will ring round too see if anyone I know has a tester

Cheers men...

Will let you know what I find out

AFAIK checking the diaphram isn't too onerous, no need to drain the oil if you do it on the side stand, could be difficult to spot though.

Good luck

Just re-read your post. If it is only smoking on start-up in the morning then it sounds like the valve stem seals. Go for a good run and then leave the bike to stand for half an hour (just enough time for something to eat and drink ) then start up and see if there is blue smoke.

White smoke on first start up in the morning is just condensation burning off

paddyz1 wrote:Just re-read your post. If it is only smoking on start-up in the morning then it sounds like the valve stem seals. Go for a good run and then leave the bike to stand for half an hour (just enough time for something to eat and drink ) then start up and see if there is blue smoke.

White smoke on first start up in the morning is just condensation burning off

Also, IIRC from my BSa etc days, when it's warmed up, if you open the throttle then shut off quickly you'll get the blue smoke with worn valve guides/seals

On dry sump engines, the sump must be as it says... dry. If there's a drain plug on the sump, take it out when been stood for a bit after a run and see what comes out.. If loads of oil, then ye pumps gone for a burton. It will also cause havoc with engine the breathing and force oil up the bores passed the rings into the combustion chamber. That's known as "wet sumping".

On start up with loads of blue smoke after a long lay up (or over night) still means the sump is filling with oil. This is known as "leak down". It happens when the seals in the pump get a bit tired and let oil pass in to the sump. It'll soon clear up as the excess oil is burnt off.

This opinion is based on my knowledge of older engines (not just Brits!).. No idea if the Rotax lumps are like this.. Valve stem seals are a possibility, but they tend to get worse when the engine is hot.

you will see the result of worn stem seals when the bike as been stood for a while,on start up the oil that as leaked into the bores gives you your blue smoke but is quickly burnt up after few seconds and clears. only to return again after being stood.

I,d go for diaphram, easy to check, remove pipe to the clutch (right side of cover) and see if smoke clears . mine did griff could see relief on my face, my pipe is blocked off at mo until diaphram turns up so no slipper clutch hope this helps

ste wrote:I,d go for diaphram, easy to check, remove pipe to the clutch (right side of cover) and see if smoke clears . mine did griff could see relief on my face, my pipe is blocked off at mo until diaphram turns up so no slipper clutch hope this helps

+1

Simple stuff first .... no point in worrying about the other stuff 'till that's eliminated.
I know the others may be from classic symptoms but these are things you don't often hear of being problematic on the rotax lumps.

Save all the other useful suggestions to be explored if the diaphragm doesn't solve it.

i´m pretty sure that your falco will look like this when you open to the Diaphragm

Sorry for the poor quality.

Hi all,

Thanks sl1000_dk, I shall have a look this afternoon, see what that reveals Hope it is JUST my diaphram

My breather tube will be relocated as well.....

OK, breather is squeeky clean There is some oil on the outer side of the diaphram Is it suppose to be completely dry, or a small amount of oil there? The oil is on the bottom of the diaphram and some coming out of the vacuum pipe attached.....

I hadn't started it, so shouls there be no oil in there

There is some blue smoke on start-up, damn annoying

Cheers.

I dont think there should be a little bit of oil in there
im sure that if you change the diaphragm you are home free.