Oil Burning

[ProXimaCore]

Right it's time I sorted my oil burning problem on my bike. It is consuming about a litre of oil per 1000 miles. I think it's actually worse than that now though. When I start it up and give it some high revs it produces some black smoke out the exhaust. It seems to be fine when it's warmed up though.

What's likely the problem and what can I do to fix it. Bearing in mind I'm not very mechanically skilled, how much do you reckon I'd get charged for someone to sort out what ever it is that's wrong? I'm guessing it's going to be a fair bit.
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Honda NSR125R -> Suzuki GSXR400R GK76a -> Kawasaki ZX636 B1H -> Honda CBR400RR NC29 -> Nothing

[swampy]

I think that high oil consumption and smoke generally points to oil being burnt in the cylinder, which in turn generally points to knackered piston rings. I don't know too much about your bike, but i'm guessing that as its mulitcylindered they might only have gone on one piston. To fix it you need to take the engine to bits and replace them If you're not to confident with a spanner in your hand, might be worth taking it to a pro..... Hope this helps.
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"I hate to advocate drugs, alcohol, violence or insanity to anyone, but they've always worked for me." Hunter S Thompson
"Faster, faster, faster, until the thrill of speed overcomes the fear of death..." Hunter S Thompson

[mr jamez]

Well yeah it could be rings, valve stem seals, valve guides?

Compression test should tell you if the rings are shot?

I would imagine a strip down on this engine would be a pretty big undertaking, perhaps it would be easier to get a replacement engine from a breakers yard

[Big Pete]

a top end rebuild isnt a huge job, a decent weekend should see it done (if you have all the parts and gaskets) You do need some tools tho, a decent socket set, a torque wrench and a valve spring compressor are all essential. Where abouts are you?
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Trust me, I`m an engineer
GarageOfPower.co.uk

[ProXimaCore]

[iCraig]

Probably the piston/oil seal rings that are knackered and need replacing.

Although most Suzuki Engines do consume abit of oil but not that much.

As has been suggested above you need to rebuild the top of the engine with new piston rings and rehone the bores or do a rebore if neccesary.

[ProXimaCore]

If I can't find someone to help me. How many hours labour are we talking for a garage to do it? Thank god it's pay day tomorrow.
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Honda NSR125R -> Suzuki GSXR400R GK76a -> Kawasaki ZX636 B1H -> Honda CBR400RR NC29 -> Nothing

[swampy]

Just had a thought, give the bike a thorough going over for any oil leaks prior to doing anything to the engine - just in case
____________________
"I hate to advocate drugs, alcohol, violence or insanity to anyone, but they've always worked for me." Hunter S Thompson
"Faster, faster, faster, until the thrill of speed overcomes the fear of death..." Hunter S Thompson

[Rory]

You could always have a chat to that Andy Bennett chap I mentioned before, perhaps not as close as you'd hope though.
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My Old CBR400RR | Bike Oil FAQ | Petrol FAQ

[beerbaron]

If you are lucky it might only be 1 or 2 rings that have some carbon and are stuck with it. You can try to put some diesel in your spark plugs and let it get into your oil pan (wait for 2 days).

Diesel is a solvant that is quite good at getting rid of carbon deposit. This is basically the cheapest thing you could try, some people got great results.

And please... change the oil when you are done... I'm sure you don't want your engine running with diesel fuel as libricant.

BeerBaron

[ProXimaCore]

Someone suggested something similar to the diesel thing except using that redex stuff.

I think I'm going to take it to a guy on the weekend to look it over. Hopfefully he can tell me what's wrong with it for sure. Then I will see how much it's going to cost.
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Honda NSR125R -> Suzuki GSXR400R GK76a -> Kawasaki ZX636 B1H -> Honda CBR400RR NC29 -> Nothing

[ZRX61]

Oil smoke is white/bluish, black smoke is petrol.... Your smoke problem is caused by it running WAY too rich, not by burning oil...

[ProXimaCore]

[stryker]

The oil could be getting into your gear box.... but it would have to come out somewhere eventually.

If you've not been playing with the mixture screw on your carb(s) the running rich thing could be worn jets, or possibly your air filter is now a gunky solid block of carbon

[ProXimaCore]

[stryker]

With the engine warmed up blip the throttle. If the revs return back to idle then fine. If they hang high then work down gently to idle then you could be rich, if they drop well below idle then climb it could be lean..... erm, think I have that right, I always have to return to the manual to check

Either way it should be returning straight back to idle if its right. Climbing revs while adjusting the mix usually means your making it richer, in my experience.

[ProXimaCore]

I went out for a test run on the bike. I even stuck the standard exhaust on it. What a difference to the sound. I never did a test for the smoking when the engine was cold though. I've heard people say that when they had the race can on, the smoke was produced. I did test it after it was warmed up after a 30 min run. No smoke at all. Also note that the bike hasn't been altered to suit the race can. So the bike should run fine with the standard can.

As for the engine idling. If I rev it, the revs take a little longer than they should to settle. Then it settles in between 1.5k to 2.5k. It's different every time.

At low revs the bike struggled to move. Accelerating like it was a car. Felt ok mid range, except when I rested it on the 6Krpm mark. It jerked around, quickly bursting forward then bogging down immediately after over and over. The top end was a struggle too. It took forever to reach the redline after it got past the 10krpm mark. In top gear it was about 4krpm off the redline and wouldn't go any more. It usually stops 500prm just off the red in top gear.

It's going for an engine service on friday morning. So we'll see what comes back from that.
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Honda NSR125R -> Suzuki GSXR400R GK76a -> Kawasaki ZX636 B1H -> Honda CBR400RR NC29 -> Nothing

[mchaggis]

The head is clean of oil and crap isn't it? I know it's not really quite the same scale, but my mum's CG125 lost about half it's oil in a fortnight through the knackered head cover gasket. Probably quite unlikely, but a possible oil leak nonetheless.

[Big Pete]

The running symptoms you described sounds like your carburettion is miles out, they probably need balancing (at least), probably a new air filter, the carbs themselves may need cleaning, and you might need a set of diaphragms. hard to tell without a set of gauges tho.
____________________
Trust me, I`m an engineer
GarageOfPower.co.uk

[stryker]

Make sure you let us know how it goes. My bike is nowhere near as bad as yours but it does share some of the symptoms, such as idling, returning to idle and stutter in low revs.

I'm interested in seeing how much you'll be charged given the probably inevitable event they have to give your carbs a right good servicing.

I'm happy playing with the carb on my reliant engined trike, but I get the feeling of dread at the thought of tinkering with the FZR carbs.

[Big Pete]

bike carbs are ok to work on, they are fairly simple, but do one carb at a time. on older stuff they can be a real bastard to get of the bike, but newer stuff with beam frames makes it easy. A decent screwdriver set, some 1/4" drive sockets, a few small spanners and a decent set of needle nose pliers will happilly do the stripping and reassembling. To balance them you need a set of vacuum gauges. If you are going to work on carbs its worth getting a washing up bowl and working over it on top of some newspaper, the bowl will catch any petrol spills as well as any small bits that you drop.


And never, ever smoke while stripping carbs.
____________________
Trust me, I`m an engineer
GarageOfPower.co.uk

[Rory]

Prox, you haven't had the cams out and retimed have you? If the timing is as off as mine was for a while, that'll completey knacker the power. Maybe your valve clearances are too.
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My Old CBR400RR | Bike Oil FAQ | Petrol FAQ

[beerbaron]

Start by cleaning the carbs, it's free, easy to do, and if it haven't been done in a few years it could be the source of a lot of problems.

Carb servicing should be done every 3 years.

BeerBaron

[ProXimaCore]

Well it's away getting sorted just now. I've to check back at 4pm. The guy reckons it'll take 4 hours of labour. So that's about £100. Hopefully, nothing much on parts will be needed, and hopefully nothing too serious is wrong.

It was funny, because the bike was actually running not too badly this morning. Not perfect but nowhere near as bad as it has been running all week.
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Honda NSR125R -> Suzuki GSXR400R GK76a -> Kawasaki ZX636 B1H -> Honda CBR400RR NC29 -> Nothing

[Rory]

Hmm, it's colder today (at least in Edinburgh), which would affect your carburation, so maybe that has got something to do with it
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My Old CBR400RR | Bike Oil FAQ | Petrol FAQ