Whats an acceptable oil consumption?

[pompousporcup...]

On a '92 gpz500, what would you say is an acceptable oil consumption?

I'm using it on the motorway every day for 2 hours (110 ish miles) at speeds ranging from 60 - 90 mph but mostly sat at 75 in 6th at around 6k rpm.

I've not noticed a drop in oil level this quick before but managed to catch the oil level just above the glass where 500 odd miles earlier it was at the top of the glass..

I understand some oil will be burned off during the combustion process, over time, but also don't want to ignore it as "oh, its an old engine! it may burn some oil" and find out mid commute that there is actually something wrong.

It rides fine, has plenty of oomph

[stinkwheel]

Any leaking out? Have a good look under it and where it's parked. Check in the airbox.

If not, it's burning the stuff. They CAN go through it quick but a sudden increase is probably cause for concern.

If it's not actually leaking, keep an eye on it and check for smoke in your mirrors. Or get someone to follow you and see if they can see smoke.

A sudden, large increase in oil consumption could mean it's developed a problem like a cracked oil control ring or a failed valve stem oil seal.

The latter would normally cause puffs of smoke from the exhaust on the overrun or when you change gear. The former would normally be worse under power.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[RhynoCZ]

The service manual should give you the exact answer.

Acceptable for me would be 1L per 5000km (the manual would say the oil consumption should not be greater than 1L per 1000km or something like that).

Now, when I had the GPz550, I also was loosing oil. Easy fix = thicker oil.

ALSO, check the oil is not leaking from the engine and check the airbox is not filling with it. If all is clean, then try thicker oil. It helped me a lot, but my GPz was aircooled, so it ran hotter and had greater gaps between all the moving parts.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[pompousporcup...]

i will need to have a tinker later tonight then and check the airbox. I have noticed the left side of the head is "wet" but wouldnt expect it to piss out that much. I suspected the rocker gasket was bad so ended up replacing it with a brand new one a couple months ago and made sure i used gasket seal (hylomar iirc)

Its also difficult to be 100% certain as thats the side stand side so water etc always seems to accumulate on that side of the engine.

There is no oil on the ground when parked all day at work or on the garage floor at night which is the first thing i checked. The sump and casing is generally covered in a mixture of motorway jizz and chain lube (which also happens to be engine oil)


I dont want to be concerned over nothing and start pulling stuff apart but also don't want it to go kaboom. i've become somewhat attached to this bike.

As i have effectively accelerated 6 months previous use into less than a month, it "could" have been this way all along and along with constant higher rpm for extended time periods, i've just noticed it now

[RhynoCZ]

[Azoth]

It's an old, high mileage bike. You're at the point now when it's almost time to make the big decision: do you like it enough to do major work on or replace the engine, or are you going to run it into the ground?

If the latter, just buy the cheapest Ebay 10W40 you can find and keep topping it up. It's only going to be a problem or MOT issue when you see billows of smoke.
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Safety in numbers

[pompousporcup...]

its only just ticked over to 21k

I've gone out and cleaned the side of the head. Its possible its leaking oil and i'l see after my commute tonight if thats the case. One thing that puzzles me is that if its losing 300+ml of oil every few hundred miles out of the rocker gasket, surely i'd see that accumulate and run down the front of the block(which isnt the case as far as i can see)

sounds like i need to do some further investigation. so generally, 1lt oil every 3.5k miles is probably alright?

[Azoth]

Much as I'm not the biggest fan of that engine, at 21k miles it would barely even be run-in, let alone worn out. So the sheer age of the bike would make me hesitate and question the mileage. However, as you know, some things can wear out more from doing nothing, which is what you saw with the aged rocker gasket.

Do you keep your engine clean on the outside? If so, run your hand around the cylinder head and the front of the block. It's possible that a leak might be invisible but oil mixing with road dirt will leave a gritty film on the block. Any overheating? How's your coolant level?
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Safety in numbers

[Nobby the Bastard]

I couldn't possibly comment...
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[CaNsA]

[RhynoCZ]

Yes, I would say 1L per 3.5k miles is alright, not ideal but alright (some modern cars burn 1L of oil quicker than that and the manufacturer says it's alright). You could try thicker oil, it helped me with the GPz.

Also, if the oil is leaking from the engine, it's actually good news. If nothing is cracked, the head gasket and valve cover seal, etc. are not expensive and are easy to change actually. Way easier than changing the piston rings and valve stem seals etc.

Have you already checked the spark plugs? The colour of them would tell you more. It would certainly determine whether your burn the oil or just leak it on the ground.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[pompousporcup...]

im fairly meticulous with maintenance but cleaning isnt something i do. Not on this bike I like having a shit kicker of a bike as a daily but im certainly not running it into the ground (oil is changed every 2.5k miles along with clearances and coolant change + more. I've just spent 200 in service and brake parts)

The mileage is genuine. Got it from an old chap who bought it new and MOT history confirms it. It had 12k when i got it

But you're right. Some things like seals wear out with age and made worse when not in constant use. I've only been doing 110 miles a day for the last 2 or 3 weeks which is why this has come to light now

[pompousporcup...]

[pompousporcup...]

[Nobby the Bastard]

is using about 400ml every 250 miles. I'll replace the valve steam seals when the valve clearence needs doing, which means in about a year and a half (15000 miles from last time they were done.)
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[temeluchus]

What's your oil measuring procedure?
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Some shite cruiser. Now with guns and FREEDOM!

[pompousporcup...]

[Nobby the Bastard]

[temeluchus]

[stinkwheel]

Valve stem oil seals can get hard and brittle with age/disuse.

Kawasakis can (in my experience) suddenly decide to drink a load of oil for no good reason too. Then stop again. So just keep an eye on the levels.

What will knacker the engine is if it runs out of oil. It can be smoking, leaking, burning and dribbling past and through every orifice and seal like the Exxon Valdeez and keep running right up to the point the valves wont close any more due to the build up of soot providing you keep it topped up. If you run out, it'll all go wrong very quickly.

If the oil pressure light comes on. Stop, go no further. On a GPZ500 it's an indicator that the oil pressure is dangerously low and your engine is lunching itself
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[base]

1 litre per 1K is acceptable as per some manufactuers, personally I think its too high but thats what some say! off topic but I read somewhere that Porsche say 1 litre per 620 miles is ok for their panarmra model .............. barmey in this day and age of "technology" and advancement in engineering.

[temeluchus]

I'm also tempted to say valve stem seals are perished frim the lack of use. They may eventually improve now they are getting a regular soaking in oil.

Switching to 15w40 or 20w50 will reduce consumption a bit, the UK doesn't get cold enough for these heavier grades to cause any issues.
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Some shite cruiser. Now with guns and FREEDOM!

[Kickstart]

Hi

Very much depends on the bike and engine. The GPZ500s we have had have not been bad on oil consumption.

Some bikes have a really bad reputation. FZR1000 for one (late FZ750 as well - early ones seemed to be fine for oil consumption).

VW have said that 1L per 500 miles was within tolerance for new cars a few years ago.

Have you changed the oil recently? Used a thinner oil than standard, or one that is the same spec but at the thinner end of the range for that spec.

All the best

Katy
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[kramdra]

None. I bought my first car with a dodgy engine, burnt 1 litre for every tank of fuel and was checking it very journey, far to much effort.

The crankcase breather can suck oil droplets up the intake. Check air filter and stick an external filter on it.

Suggest putting a litre of Motul 7100 10w/40 in.

My cbr6 now done almost 80k miles and does not use any.

[Nobby the Bastard]