White smoke when accelerating
White smoke when accelerating
Author
Discussion

TheThing

Original Poster:

960 posts

164 months

Monday 31st August 2020
quotequote all
Hi all. Went for a blast today and the bloke behind me said that when I accelerated hard there was a small puff of white smoke coming from the exhaust. Bike is an SV650S. Is this likely to be a problem? He said it smelt a fair bit. I recently changed the oil and filter. Coolant level is slightly under full. Any one got any ideas. Thanks. Praying that this isn't a head gasket.

Steve Bass

10,753 posts

263 months

Monday 31st August 2020
quotequote all
TheThing said:
Hi all. Went for a blast today and the bloke behind me said that when I accelerated hard there was a small puff of white smoke coming from the exhaust. Bike is an SV650S. Is this likely to be a problem? He said it smelt a fair bit. I recently changed the oil and filter. Coolant level is slightly under full. Any one got any ideas. Thanks. Praying that this isn't a head gasket.
You may have hit the nail on the head sadly frown

Keep an eye on your engine oil and look for any white mayo that builds up if water is mixing with the oil.
A quick compression test might be worth doing as well, see if you're down on a cylinder...

TheThing

Original Poster:

960 posts

164 months

Monday 31st August 2020
quotequote all
Thanks for the reply. I checked when I got home and gave the bike a rev while stationary. Its not thick smoke. More like a thin vapour if you give it the beans. Would it not be obvious if it was down a cylinder it being a twin? Its not making any unusual noises and there is no mayo build up in the oil. Its not a particularly old bike. Its a 16 plate with 20000 miles on it.

RSTurboPaul

13,124 posts

288 months

Monday 31st August 2020
quotequote all
Keep an eye on coolant levels - if it drops over time, that would point towards a HG.

IMO just keep using it till it breaks or until you're putting more water in than petrol biggrin lol

Iminquarantine

2,168 posts

74 months

Monday 31st August 2020
quotequote all
White smoke = head gasket is the general rule.

Other possibility is someone hid crack cocaine in your tailpipe but didn’t come back to get it in time and it was burning off. But I think the head gasket is more likely.

Chainsaw Rebuild

2,138 posts

132 months

Monday 31st August 2020
quotequote all
Keep an eye on the coolant level. if it drops then its probably the HG.I wouldn't just keep topping the coolant up! that could ruin the bearings if the oil is polluted with water or overheat and warp the head.

Take it into a garage and ask them to have a look at it. a compression test shouldn't be very expensive, and a HG wont be the end of the world, especially at this early stage because it hasn't overheated or ruined the bearings.

trickywoo

14,237 posts

260 months

Monday 31st August 2020
quotequote all
Those engines are pretty indestructible so while it could be HG I’d find it unlikely at that age and mileage.

Sure it’s the correct oil filter and not been overfilled?

Is it standard?

TheThing

Original Poster:

960 posts

164 months

Monday 31st August 2020
quotequote all
trickywoo said:
Those engines are pretty indestructible so while it could be HG I’d find it unlikely at that age and mileage.

Sure it’s the correct oil filter and not been overfilled?

Is it standard?
Ye they have got a good reputation for reliability. Been around for 20 odd years now so they are tried and tested. HG failure is pretty rare for an SV as far as I'm aware but that doesn't mean it won't happen to me! Only mods are an end can and K and N air filter. Ye definitely correct filter and definitely not over filled.

mad4amanda

2,410 posts

194 months

Monday 31st August 2020
quotequote all
How warm was the engine when this happened was it the start of a ride or the end?
It been pretty chilly today and what was seen could just be getting rid of condensation and nothing to be concerned about.

TheThing

Original Poster:

960 posts

164 months

Monday 31st August 2020
quotequote all
Oil filter was a HF 138 and the oil was filled to a smidge under the full line on the glass. Oil used was Castrol power 1 10w40 fully synthetic

TheThing

Original Poster:

960 posts

164 months

Monday 31st August 2020
quotequote all
mad4amanda said:
How warm was the engine when this happened was it the start of a ride or the end?
It been pretty chilly today and what was seen could just be getting rid of condensation and nothing to be concerned about.
It was quite far into the ride. Maybe 25 miles. Person behind said it was happening when I whacked the throttle fully open. Just a very faint puff of white smoke. That stank.

Pope

2,653 posts

277 months

Monday 31st August 2020
quotequote all
Maybe dodgy fuel? Was there any feeling of power loss? White smoke isn't always coolant - you'll get it with too much oil or fuel too - I've seen a few injectors go full open and that can be pretty spectacular (think low-level red arrows display team!!)

Might be worth checking the plugs - if it is a head gasket then I'd expect to see a really clean plug on the offending cylinder. Pressurise the cooling system and leave the plugs out over night - if it really is gone you'll end up with coolant in the cylinder which you'll see when you next wind it over......

trickywoo

14,237 posts

260 months

Monday 31st August 2020
quotequote all
HG is pretty easy to rule in or out so definitely check but I’m thinking fuel related.

Have you checked / changed the plugs?

Moulder

1,648 posts

242 months

Monday 31st August 2020
quotequote all
I am going for oil collected in the airbox if it has been over filled at the last change. Also one of the cheaper/easier things on the list to check.

TheThing

Original Poster:

960 posts

164 months

Tuesday 1st September 2020
quotequote all
Thanks for all of the replies. It is much appreciated. I didn't change the plugs this time round as they were done at the last service 4000 miles ago but I will get them out and have a look. I will also check the air filter for oil. As for fuel, nothing dodgy, that last full tank was from a well known supermarket station. Also no power loss either. Engine feels completely normal.

stang65

593 posts

167 months

Tuesday 1st September 2020
quotequote all
TheThing said:
It was quite far into the ride. Maybe 25 miles. Person behind said it was happening when I whacked the throttle fully open. Just a very faint puff of white smoke. That stank.
At the risk of over simplifying...if it stank, what did it smell of? Coolant, fuel and oil all smell completely different even when burnt in an engine. Unfortunately a little fluid gives a lot of smoke so it may be a while before a level change shows which it is (and if it's fuel you'll be filling up anyway). If coolant it should be more like steam which "evaporates" quickly, whereas running rich tends to give blacker smoke and oil smoke has a blue tinge. Oil and fuel smoke tend to take longer to disperse. Obviously all a generalisation.

Pulling the plugs will be worthwhile as you can compare the two and see if there is an issue on one cylinder and at least narrow things down.

carinaman

25,273 posts

202 months

Tuesday 1st September 2020
quotequote all
16 plate SV has a Catalytic Converter? Was it a Cat Fart?

Hungrymc

7,439 posts

167 months

Tuesday 1st September 2020
quotequote all
Might be not combusting very cleanly. iffy spark, poorly atomized fuel ? that can make smoke which is black when its extreme but is a bit more white when its less significant.... I think

TheThing

Original Poster:

960 posts

164 months

Tuesday 1st September 2020
quotequote all
carinaman said:
16 plate SV has a Catalytic Converter? Was it a Cat Fart?
Its an L2 so as far as I'm aware was built in 2012 and sat in a dealer for 4 years before anyone decided to buy it. I might be wrong but I thought on sv's the cat was in the end can. Mine has got an aftermarket can on it so no cat?

carinaman

25,273 posts

202 months

Tuesday 1st September 2020
quotequote all
TheThing said:
Its an L2 so as far as I'm aware was built in 2012 and sat in a dealer for 4 years before anyone decided to buy it. I might be wrong but I thought on sv's the cat was in the end can. Mine has got an aftermarket can on it so no cat?
No Cat so not a Cat Fart.