Smokey VX800

Hey everyone.

I know there's few VX800 riders on here but know that the VS800 was so popular and the VX800 was based off the VS I'm pretty sure there is a wealth  of knowledge to be had. 

First things first! 

I've owned my bike for 5 days now and when I took ownership of the bike it had been sitting for 2 months that I know of but unsure how long before that. 

Story so far. Bike was owned by an older rider since new in 1991. He rode it for a pink slip (road worth check 2 months ago) and come to the conclusion that the bike was to heavy for him to ride. 
I noticed that the fork seals are leaking and that is pretty much making the bike super heavy. 

But now on to my problem. 

Bike starts and idles with no choke, first go perfect. 

I rode the bike around my bloke 3 times (maybe 600 meters at most) and it started blowing very heavy smoke. 

I put it in the shed and thought I'd sleep on it. 

At this point I'd like to mention that the previous owner used WD40 (multipurpose cleaning and  lubricating spray) in the exhaust to prevent internals rusting. 

I then decide the next day to replicate the results while the bike was stationary. 
 
I let the bike idle for about 5min then took the rpm up to 4k and let it sit. 
Sure enough after a further 5min it starts blowing grayish smoke. 
It starts off in one pipe (non discriminate) then slowly starts in the other. 

I've repeated this over the last couple of days and found the same results. But the smoke smells very high in fuel. There's no sign of oil spitting out the pipes and only condensation forms on your hand if placed I front of the exhaust. 

I've been given heaps of advice on where to start and 
"don't panic"

What I'm planing on doing is starting from the ground up. 
I'll drop the oil out and replace it along with the filter. 
I then need to get it registered and take it on a nice long ride. 

If after this It's still getting smokey, I'll be trying vales and  carbs. 

Cheers for any and all advice. 

Only1MADMaN wrote:

At this point I'd like to mention that the previous owner used WD40 (multipurpose cleaning and  lubricating spray) in the exhaust to prevent internals rusting. 

It will smoke like hell if WD40 has been sprayed inside the exhausts until it has all been burnt off.

If it was a cracked head or cylinder. Would it not smoke from start?

And

How long would it smoke for until the WD40 is burnt off. Let's say it's been sprayed inside the muffler for the last 5 years every month??

It only happens after the bikes been running for 5 min..
Shut bike off wait 5min, start bike again then wait till warm.....blows smoke?

What does the smoke smell like??

WD40 sprayed inside the exhaust is not really that bad but it will burn off but the residue rather quickly as the exhaust gets very hot.
Check your spark plugs, always a good place to start. Black soot on the spark plugs would indicate that the air/fuel mixture is very rich, this will result in grey smoke coming out of the pipes.Also either clean or replace the air filter as that not flowing properly can result in grey smoke because it will make the engine run rich. you could also adjust the air/fuel mixture, you will have to drill out the little brass caps that cover the mixture screw. Don't worry about taking a drill to them & drilling them out, this is done on most carbs bikes for adjusting. Another step might be putting new needles in, in that case I would definitely buy dynojet needles rather than replacing the stock needles with stock needles.

Hi Adam,

Check the oil level ..... if it is over full then you could have a bike that has suffered from a faulty petcock that has allowed fuel to pass through it when the engine is not running.

This can lead to petrol getting into the crankcase .... which in turn can lead to oil burning when the bike is running ...but changing the oil would remedy the contaminated oil.  

Could be worth looking at the air filters - the rear one is the easiest to get to - if that has a strong petrol smell then it could indicate a leaky petcock issue. Its also worth checking the air filters, cos if it starts without choke they could be well blocked - the rear one will be the worst (usually) cos its near the back wheel and draws on dirtier air than the front one !

I see yours is a 1991 'VX', which if I remember correctly has an 'off' position on the petcock (The later models don't have an off position).

There are several threads on petcock repairs & replacement parts can be sourced from Kawasaki as Suzuki don't seem to offer the smaller parts for a 're-build'

As mentioned by others - if WD40 has been sprayed down the exhaust then it will smoke for a while ....also some 'old noggers' but some two stroke oil in the petrol when laying up a bike - so if the fuel has oil in it then that will make the motor smoke - but it is generally harmless.

As you say - it really needs a good run first to make sure you are not trying to fix a problem that is not there .... I'd be tempted the drain the tank, put fresh fuel in, then run it for 100 -150 miles and re look at it.  Only exception being if the oil level is over full - then I'd do an oil change before the 100-150 mile run.

As mentioned by Andrew - next jobs would be checking carb balance/synchronisation, then valve clearances .... though in fairness you should 'hear' if the valve clearances need adjusting.

When you start riding the bike you may think the clutch is slipping occasionally - this is a fairly common issue and it is addressed in other threads. But start by checking clutch adjustment - the one inside the transmission cover being the most neglected check.

Hope that gives you some food for thought

 Yam

If the smoke smells high in fuel as you have stated, then as already been suggested a good place to start would be the fuel to air mixture.

Wow!

Thanks heaps for the response, everyone has given me heaps to look at and that's what I need. 

There is so much to look at on a 23 year old bike. I'm defiantly going to drop oil and check air filters and choke cable. 

Cheers again

So I've dropped the oil and replaced the filter.

I defiantly only put in the recommended 2.8 litres and a couple of mill ether way shouldn't cause problems. 

I've not yet got it on the road but can say this. I've still get smoke through the left exhaust which is cylinder 1. It's far to say its blueish now I've had a good look. 
It was hard to track down but I'm sure I've got a ring/valve seal problem  :shithhappens: 
But I'm still going ahead with rego and getting this thing on the road before I make any major steps towards stripping the engine and getting the Doctors in. The bike is so good in every other aspect and on inspection before buying. 

It could remedy itself but I'll keep everyone posted on where I'm at.

So....... What's the damage on a rebuild?

Hey OldManYam

This VX800 had a "on,off,res" from factory but it failed and at 5000klm it went bang!
Under warranty it he engine was replaced. 

After that they retro fitted the  vacuum "res,on".  

Cheers

If you have only just bought this bike from a dealer, you are in your rights to take it back to have any faults rectified, any purchase has to be fit for purpose.

Nah private sale. 
That's the game we play.

Adam,
My approach to this problem would be, not to start stripping the machine down but to change the oil and filter then a good doze of Redex into the carbs. If the piston rings are sticking you would get the symptoms you have described and Redex is a good economical starting point.

G Terence

Just giving everyone that has offered advice so far an update

Bike has been off the road for 3 months cleaning painting and replacing parts. 
Finding problems with everything from missing internal fork parts to finding 
That someone had butchered the pistons in the brakes needing a rebuild. 

As for the smoke I think it's valve stem oil seals. 

Still piecing it back together.

Only1MADMaN wrote:

As for the smoke I think it's valve stem oil seals. 

Hi, One experience I had with worn valve stem seals was, When the engine idled for a period of time, the blue smoke built up in the exhaust and came out heavily until clear, but once the engine was running at a constant riding rpm there was no smoke, I suppose it depends on the severity of the worn seals? but a very small amount of engine oil in the combustion chamber creates a lot of blue smoke.

Yes .... & the early BMW K100 (8-valve) was prone to 'heavy smoking' on start up ... a problem from the 'flat inline-four' layout, cos when the bike was parked on the side-stand oil could fill the OHC area leaving a lot of oil around the valve stem seals, which would often let some of the oil pass through. If the bike was parked like that for some time (especially thinner warm oil) there was the opportunity for oil to build up in the inlet part of the cylinder head, that the engine would obviously 'burn off' upon start up, but made the bike's engine look in worse condition than it actually was. My buddy Steve had an early K100, that could do a good impersonation of the Red Arrows smoke trails if the bike had been on the side stand for some time .... not sure if he exploited that fact as a 'party-piece' - but the level smoking would put most people of buying such a bike, but the bike itself ran very well, and I know the two  people who subsequently owned the bike & they all had no issues with how the bike ran - & it gave them decent service. It's probably still out there now somewhere - smoking away ! 
From that it would seem prudent to follow the above advice, including use of Redex (or similar), to 'clean up' the engine, then give it a good run, as the smoking issue may sort itself out.

The usual reason for failure of valve stem seals is that the seal material has hardened. If I had an engine with 'aged' stem seals I would not be worrying too much about it, unless I had other work to do on the engine ..... I would not strip an engine down just to do the stem seals - I'd sooner let it burn a little more oil & keep topping up the oil level (a slight burning of oil won't hurt anything, and can be beneficial to other components - such as silencer internals !)

Hope some of that might help, or encourage you.

  Yam

Thanks Simbo and Old ManYam. 

It's good to get as much knowledge as posable to diagnose a problem. I'm not too stressed as it's all reparable and the bike is a bit of a Classic in modern terms. I'm very smitten with my VX800 and know I'm not just getting an old bike on the road but a piece of Suzuki history working again. 

I will keep you all posted. 

Cheers.

With you there Adam    ... the VX is a much under-rated machine, & at least 2 or 3 of us think its a classic !
Cheers  Yam