Bike blowing smoke - any ideas?

[ACT_Cross8]

I've bought a 1990 GSX-R1100 and have been tinkering with it to get registered and back on the road. It's almost ready to go, but it's blowing whitish-grey smoke out of both exhausts once it warms up, which I'm guessing will be picked up at inspection.

It sat for 2 years without running before I bought it, so I'm guessing it may have a stuck oil ring or cracked valve stem oil seal or something.

Any other possible causes? How can I go about diagnosing the problem?

Thanks in advance...

[steve_t]

Could be a blown head gasket :bawl: Check for discolouration/bubbling of the coolant

[Road Warrior]

How many K's? How does it go when ridden? Does it overheat?

Is it blowing oil smoke or does it seem like the mixtures are off?

[ACT_Cross8]

Could be a blown head gasket :bawl: Check for discolouration/bubbling of the coolant

It's the oil cooled model :confused:

[ACT_Cross8]

How many K's? How does it go when ridden? Does it overheat?

Is it blowing oil smoke or does it seem like the mixtures are off?

I haven't actually ridden it since I bought it, just fired it up and warmed it up in the garage. Bought it unregistered and in pieces, so I'm still just putting it back together. I've fixed up the clutch and bled the brakes, no reason why I couldn't sneak around the block I suppose...

It runs ok and revs cleanly, so I don't think it's carb-related (wish it was...). Any steps I can run through to diagnose the problem?

[steve_t]

It's the oil cooled model :confused:

LOL. So it is... sorry :hide:

[Road Warrior]

I haven't actually ridden it since I bought it, just fired it up and warmed it up in the garage. Bought it unregistered and in pieces, so I'm still just putting it back together. I've fixed up the clutch and bled the brakes, no reason why I couldn't sneak around the block I suppose...

It runs ok and revs cleanly, so I don't think it's carb-related (wish it was...). Any steps I can run through to diagnose the problem?

Well if it were me, I would take it out and give it a hiding, and see if that helped it (seriously). Things could be just gummed up and all it needs is a decent run/thrash to get things all nice and hot and flowing again.

Whitish-grey smoke kind of indicates to me that your mixtures are off, if the rings or valve stem seals were stuffed then the pungent blue oil smoke would be coming out.

Jap bikes of any age generally aren't known for ring or valve stem seal failure and if the oil cooling system was dicky there would be other symptoms starting to rear their ugly head when you ran it.

[ACT_Cross8]

Well if it were me, I would take it out and give it a hiding, and see if that helped it (seriously). Things could be just gummed up and all it needs is a decent run/thrash to get things all nice and hot and flowing again.

Whitish-grey smoke kind of indicates to me that your mixtures are off, if the rings or valve stem seals were stuffed then the pungent blue oil smoke would be coming out.

Jap bikes of any age generally aren't known for ring or valve stem seal failure and if the oil cooling system was dicky there would be other symptoms starting to rear their ugly head when you ran it.

Thanks Roadie, Looks like I'll have to dust off the leathers then... :burnout:

[Blown 454 AWD]

Sounds like an extreme flush could help

Cheers

Steve

[ACT_Cross8]

Sounds like an extreme flush could help

Cheers

Steve

Worth a shot before pulling down. Details please?

[XUV]

I haven't actually ridden it since I bought it, just fired it up and warmed it up in the garage. Bought it unregistered and in pieces, so I'm still just putting it back together. I've fixed up the clutch and bled the brakes, no reason why I couldn't sneak around the block I suppose...

It runs ok and revs cleanly, so I don't think it's carb-related (wish it was...). Any steps I can run through to diagnose the problem?

was the motor out of the bike when you got it ??

[ACT_Cross8]

was the motor out of the bike when you got it ??

No, why is that?

[Blown 454 AWD]

Worth a shot before pulling down. Details please?




Flush for 2 hours, leave overnight, flush for another hour next morning, (all @ 20% with Mainlube 245a Flushing Additive)

We've had some great feed back from this product.

Need to unblock the slots in the oil rings and pistons behind the oil rings to allow the scrapped oil from the bore back to the sump, or you have an oil pump instead of an oil scavenger.

Cheers

Steve

[XUV]

No, why is that?

if the motor was out and stored upside down on it's cylinder head oil could have got in the valves .,

If itwas sitting there for over a year ,
you probably should have cranked the motor over a fair bit ,
to get the oil up into the rings before giving it some fuel .

It mite have a cracked ring .

Did you pressure was it before tinkering - this mite have done the damage .

Does it still rev out o.k. , or is there a resistance to rev .

How much smoke is there ,can you put up with the smoke or is it a smoke screen .

[ACT_Cross8]

I changed the oil and the plugs and flushed the old fuel out first up. It took a loooong time to get it started, so there was plenty of cranking to get the oil flowing before it fired up. I flattened the dodgy battery twice trying to get it going (part of the reason I got it so cheap I think, I made an offer on the basis that it wasn't running, then it fired up just before I put it on the trailer and took it home!).

[ACT_Cross8]

Ok, update time:

I took the bike for a bit of a squirt yesterday and it no longer blows smoke. It does, however, run very rough and loses power while revving out, between 3,500 and about 5,000rpm. It then seems to clear its throat and revs out smoothly and cleanly to over 10,000. It's less noticeable, but still there, when rolling the throttle on smoothly and slowly, but it's pretty bad when cracking the throttle open from about 2,000rpm.

Sounds like you may have been on the money Roadie. Any further suggestions appreciated, thanks.

PS. I forgot how hard these things go. Scared myself at one point :shock:. I can only imagine riding one of the new litre bikes :bow:.

[steve_t]

Have u replaced the spark plugs?

[ACT_Cross8]

I guess you missed this, steve_t...


I changed the oil and the plugs and flushed the old fuel out first up.

[steve_t]

Damn it.... sorry dude. I gotta learn to read. I'm gonna leave this thread alone now. Good luck :confused::smilesandbanana:

[ACT_Cross8]

It's all good :jester:

[Road Warrior]

Ok, update time:

I took the bike for a bit of a squirt yesterday and it no longer blows smoke. It does, however, run very rough and loses power while revving out, between 3,500 and about 5,000rpm. It then seems to clear its throat and revs out smoothly and cleanly to over 10,000. It's less noticeable, but still there, when rolling the throttle on smoothly and slowly, but it's pretty bad when cracking the throttle open from about 2,000rpm.

Sounds like you may have been on the money Roadie. Any further suggestions appreciated, thanks.

PS. I forgot how hard these things go. Scared myself at one point :shock:. I can only imagine riding one of the new litre bikes :bow:.

Hmm. Did this model use flat-slide or CV carbies do you know?

I still reckon the mixtures are all over the shop and all the carbies are probably way out of sync anyway. Motorbike carby tuning is like suspension - one of those dark arts that heaps of people say they are good at but few can actually master!!

Will the motor idle or do you have to keep it on the boil? Does it miss or pop or backfire??

[ACT_Cross8]

Hmm. Did this model use flat-slide or CV carbies do you know?

BST36SS Mikunis, don't think they are flatslides.


Will the motor idle or do you have to keep it on the boil? Does it miss or pop or backfire??

It idles ok, after I initially turned the idle speed up to 1000rpm or so, as it was stalling at first.

It doesn't miss or backfire, just sort of dies like it was starving for fuel, then it jumps back to life over 5000rpm.

[Road Warrior]

It idles ok, after I initially turned the idle speed up to 1000rpm or so, as it was stalling at first.

It doesn't miss or backfire, just sort of dies like it was starving for fuel, then it jumps back to life over 5000rpm.

1000rpm or thereabouts is where it should be.

Here is a tech article on the oil-cooled Gixxer carbies - you may have to do a little carby tear-down to make sure everything is all good before going any further:

http://www.gixxer.com/forums/showthread.php?t=159718

Also check if this model has a permanent in-tank fuel filter - it could be clagged up with crap and hence contributing to your starvation problem.

[ACT_Cross8]

Great article, thanks for that (still trying to get my accountant-brain around it though...).

I got some 245a oil off Steve and was going to do a flush, but I couldn't get the bike started this morning :vpo:. Pulled a couple of plugs (which were brand new) and they are all black and sooty (carbon fouling according to the pics in my Haynes manual) and the spark was VERY weak when cranking it over.

I did notice the plug leads look fairly ordinary also, with a couple of cracked tops on the insulators. Anyone know where I can source some new leads to try?

[old holden V8]

Great article, thanks for that (still trying to get my accountant-brain around it though...).

I got some 245a oil off Steve and was going to do a flush, but I couldn't get the bike started this morning :vpo:. Pulled a couple of plugs (which were brand new) and they are all black and sooty (carbon fouling according to the pics in my Haynes manual) and the spark was VERY weak when cranking it over.

I did notice the plug leads look fairly ordinary also, with a couple of cracked tops on the insulators. Anyone know where I can source some new leads to try?

I'd give the carburettors a real good flush/clean. You say the bike was sitting for an extended time? If so, it might mean that jets, etc are blocked with sediment/fuel varnish/dirt.

Check & clean and check float levels. All to stock settings to begin with.
(Have fun getting them out! :))

PS...Check obvious things like air cleaner, plug gap(s), fuel fliter - and inside the tank. Check for rust. Remove fuel taps, Drain and pour in a liter of metho. Drain and pour in another liter, flush and then remove as much as you can!

H.T lead & caps also would not be a bad idea to change, if you can. I have not worked on a Japanese machine for a while - but some have H.T lead moulded at part of the coil, so you can't remove them (all one assembly). But if they seperate, you can get H.T lead (I prefer copper with suppressed plug caps) from a bigger bike shop. Use NGK - and check OEM suppression value before you get them.

I think Suzuki's of that vintage (memory hazy...) have issues with igniters - but dunno if they just dies (no spark) or intermittent like you have.

Once you have all that checked/in spec (Carb floats level, cleaned & adjusted properly) and good ignition system with a nice fat spark, then you can chase your other problems.

Oh - nearly forgot. Check and if possible pull apart every electrical connector plug and inspect.

Your machine is getting on and a corroded connection on a critical ignition connection could mean trouble like you have. OR a P.O (Previous owner)
has fiddled somewhere..

Sorry it I have given you a lot of Homework! But if you work through it methodically you WILL get there.

I have an old bike too; it has had had it's share of the issues you described above. (currently with gearbox & final drive blues $$$)

:):):)


Cheers & HTH
Laurie.

PS. Drain and check for rust in tank. Flush with metho TWICE - drain and refill with clean fresh 95/98. Check inside for rust!

[ACT_Cross8]

Well, I finally got my act together and pulled the carbs off to give them a good clean. Found a possible cause of the problems; small bit of water in one flaot bowl and 2 of the emulsion tubes all clogged up with gunk! All cleaned now and probably going back on the bike this arvo.

I did notice a couple of the float bowl gaskets looked a bit marginal, as did a couple of o-rings. Does anyone know where I can buy rebuild parts for the Mikuni carbs? I've seen a few on EBay, but they are all overseas.

Thanks again!

[ACT_Cross8]

Problem solved! Well, almost...

Bike runs a lot better now, with only the slightest flat spot around 4-5000rpm. It's very satisfying to have removed, dismantled, cleaned and reassembled the carbies myself (despite the skinned knuckes and all the swearing!). I'll take it in for a tune up soon (and finally get it registered) :)

[cashie]

I think a tune will sort out the last of the running issues... good job on the DIY and getting it running!!