1987 GN250 cam chain/oil issues

[GDOBSSOR]

Hi. I've just got my hands on a 1987 GN250. I was wondering about a couple of things. How do I know if the cam chain needs adjusting?
It also doesn't like to go above 40kph in 3rd gear, although it can do 50. Is this normal?
And, how often should I have to top up oil? In the first week and a half of having it, it went down from being 3/4 full to a little above the min line and I put more in. Since Saturday, I've done quite a bit of riding on it, but it's already used almost a quarter of a tank. Again, is this normal? If not, what is the problem? There aren't any leaks on the garage/drive, and it doesn't produce any smoke.

[FJRider]

Hi. I've just got my hands on a 1987 GN250. I was wondering about a couple of things. How do I know if the cam chain needs adjusting?

You can hear the rattle over the noise of the exhaust/engine.


It also doesn't like to go above 40kph in 3rd gear, although it can do 50. Is this normal?

Yes.


And, how often should I have to top up oil? In the first week and a half of having it, it went down from being 3/4 full to a little above the min line and I put more in. Since Saturday, I've done quite a bit of riding on it, but it's already used almost a quarter of a tank. Again, is this normal? If not, what is the problem? There aren't any leaks on the garage/drive, and it doesn't produce any smoke.

The production of a (noticeable) blue smoke trail following you .. does not mean it is not "burning" oil ...

If you don't add oil if the level is low ... it will stop. Depending on the speed that you are traveling at ... how spectacular the result of said "stop" ...

[GDOBSSOR]

You can hear the rattle over the noise of the exhaust/engine.



Yes.



The production of a (noticeable) blue smoke trail following you .. does not mean it is not "burning" oil ...

If you don't add oil if the level is low ... it will stop. Depending on the speed that you are traveling at ... how spectacular the result of said "stop" ...

My boss (an experienced motorcyclist) test rode it and said he couldn't hear anything. It's got a noticeable rattle, but a lot of people have said it's 'GN character' so I'm a little confused.
I check oil level at least once a day and don't ride it if it's below min line. However, it does seem to be going through it kinda fast.

[FJRider]

My boss (an experienced motorcyclist) test rode it and said he couldn't hear anything. It's got a noticeable rattle, but a lot of people have said it's 'GN character' so I'm a little confused.
I check oil level at least once a day and don't ride it if it's below min line. However, it does seem to be going through it kinda fast.

The "Rattle" will be worse if the oil level is low.

How many km's on the Odo .. ???

When the cost of replacement oil (keep a record of how much) ... exceeds cost of replacement fuel ... paint it Yellow.
Lemons are (almost) always yellow.

Small bikes don't hold much oil to start with ...

[GDOBSSOR]

How many km's on the Odo .. ???


Rattle is there all the time, except when engine idles.
I got it with around 23000 ks on the odometer.

[Rhys]

Give it an oil change, use the manufactures recomended grade, motors some times use more oil if it is the wrong grade or old

Its a GN keep the oil near the full mark and it will go for ever :msn-wink:

and most of all have fun!

[FJRider]

Rattle is there all the time, except when engine idles.
I got it with around 23000 ks on the odometer.

I'm thinking an '87 GN250 will have done more than 23,000 km's ... most likely it's been "round the clock". (at least once) ... 123,000 km's would be more likely.

I hope you got it cheap. They were never renown for their performance from new. The cam chain will be the least of your worries ... (and a rattle is normal) Keep the oil up to it ... a cheaper option than an engine rebuild.

It's oil use will keep you broke anyway ...

[GDOBSSOR]

I'm thinking an '87 GN250 will have done more than 23,000 km's ... most likely it's been "round the clock". (at least once) ... 123,000 km's would be more likely.

I hope you got it cheap. They were never renown for their performance from new. The cam chain will be the least of your worries ... (and a rattle is normal) Keep the oil up to it ... a cheaper option than an engine rebuild.

It's oil use will keep you broke anyway ...

I looked at what it said on the registration cert and it said 23000 ks, and it had few ks racked up between odometer readings.
It was that or a Chinese GN. It goes ok.
I got it at an ok price. I have about a grand left if the worst happens and can put money on my student loan if I absolutely have to. Obviously, I'd rather not do that. How often should it need changing once all the old oil's been filtered out (Boss recommended I do an oil change two weeks after initial oil change to filter out old oil - will do one on Friday afternoon.)
And, Wgtn motorcycles have Castrol 4 stroke oil. Any other oil you'd recommend?

[GDOBSSOR]

[QUOTE=FJRider;1130436561]The cam chain will be the least of your worries ...
[QUOTE]

What else will I have to look out for?

[FJRider]

I looked at what it said on the registration cert and it said 23000 ks, and it had few ks racked up between odometer readings.
It was that or a Chinese GN. It goes ok.
I got it at an ok price. I have about a grand left if the worst happens and can put money on my student loan if I absolutely have to. Obviously, I'd rather not do that. How often should it need changing once all the old oil's been filtered out (Boss recommended I do an oil change two weeks after initial oil change to filter out old oil - will do one on Friday afternoon.)
And, Wgtn motorcycles have Castrol 4 stroke oil. Any other oil you'd recommend?

Sorry ... I think it's done a few more than that. Rego certs are not the best thing to determine accuracy of the mileage records. How far back do the record of ownership changes do you have ???

It'll probably (will) need a new filter too. For a quick flush of old oil ... use the cheapest you can find, not CAR oil. Only needs to be a few km's before you dump it. Then go as WMC said.

An OK price means you ride ... not take the bus. Don't spend money on it. Keep the oil up to it. Keep it legal. Get third party insurance ... and start saving for your next bike. LAM's is good ... check out the list. You are no longer restricted to a 250. So learn ALL you can with this bike ... then move up.

Go Girl ...

[FJRider]

What else will I have to look out for?

Hot guys ....( Enjoy the rides ) ...

And carry a notebook and pen ... to write down their phone numbers ...

[Paul in NZ]

A GN250 holds about one liter of oil. Its a tiny amount as it lubricates engine and gearbox.

Yes - it uses heaps, they all do but yours does seem a little excessive maybe. At the moment, dont stress about it, check the oil every time, top it up and change it regularly and enjoy.

[Flip]

I would change the oil for some fresh stuff and ride the bike. Some times motors that sit around seem to gum up and burn oil. This usually comes right with use. I would just ride the bike and see if the oil usage improves. Castrol do make a good product.

A worn can chain sounds like a bad rattle at idle.

Ride and have fun.:yes:

[FJRider]

I would change the oil for some fresh stuff and ride the bike. Some times motors that sit around seem to gum up and burn oil. This usually comes right with use. I would just ride the bike and see if the oil usage improves. Castrol do make a good product.

A worn can chain sounds like a bad rattle at idle.

Ride and have fun.:yes:

And if the GN has only done 23,000 km's ... this may well be the case with your bike.

Drop by Wellington Motorcycles when you get the oil ... and get them to have a listen to the Cam chain.

And if the wind isn't too bad over the weekend .. blast over the 'Taka's for a coffee in Featherston. A good run will do it AND you the world of good.

Enjoy ...

[GDOBSSOR]

A GN250 holds about one liter of oil. Its a tiny amount as it lubricates engine and gearbox.

Yes - it uses heaps, they all do but yours does seem a little excessive maybe. At the moment, dont stress about it, check the oil every time, top it up and change it regularly and enjoy.

Hi. How regularly should I do a complete oil/filter change? Would every 3 months be about right?

[Paul in NZ]

How often do you ride it...

I would change it every 1000km on one of them as it gets a hard time and check it before every ride.

[GDOBSSOR]

How often do you ride it...

I would change it every 1000km on one of them as it gets a hard time and check it before every ride.

I check it before every ride.
I keep getting different opinions from different people about how often to change it so I'm confused.
The service manual says change it every 5000 km.
Wellington Motorcycles said between 3000-4000 km.
You've said every 1000 km? Why would it need to be that frequent it the service manual hasn't said so?

[ducatilover]

Every 5000km is fine to change it
It takes 1.3l of oil and runs a very common and cheap filter

Rattles, they're a wee bit ticky being an air cooled single with tappets
Cam chains do wear
Cams will wear and so will rockers

If it gets horribly loud I may be able to help, valve clearances are piss easy to do (30min comfortably) I have a new cam chain, cam and rockers (I think I have two new cams...) and can fit them

For what it's worth, my last GN motor let go after having a horrid rattle, which turned out to be the bottom end bearings going, which led to crank float and valve-piston action. Not a common thing though :msn-wink: probably something to do with the "hot" motor it had

[Paul in NZ]

I check it before every ride.
I keep getting different opinions from different people about how often to change it so I'm confused.
The service manual says change it every 5000 km.
Wellington Motorcycles said between 3000-4000 km.
You've said every 1000 km? Why would it need to be that frequent it the service manual hasn't said so?

There is a trend for manufacturers to push out service intervals to the extreme limits. IMHO they are often very very optimistic or have access to super oil. The factory are assuming the dealer will do it so its a costly exercise and off putting to some owners. I was brought up by a mechanic whos motto was oil and petrol are the cheapest things you will ever put into a vehicle.

You asked how often 'I' would change the oil and I said I would change it every 1000km BUT I would do it myself and I might modify that opinion if I noticed that the oil was still clean and good at 1000km.

I change the oil in my ancient Triumph at about 1500km and its usually well ready for a change by then but it runs a good filter and holds 3litres.

Your bike may have an issue or two so I would change it more regularly than if it was new. As the engine wears its likely to pollute the oil a bit more hence the 1000km suggestion. End of the day its your bike and you can change it whenever you like or never if that suits too - its not bothering me a jot.

[ducatilover]

There is a trend for manufacturers to push out service intervals to the extreme limits. IMHO they are often very very optimistic or have access to super oil. The factory are assuming the dealer will do it so its a costly exercise and off putting to some owners. I was brought up by a mechanic whos motto was oil and petrol are the cheapest things you will ever put into a vehicle.

You asked how often 'I' would change the oil and I said I would change it every 1000km BUT I would do it myself and I might modify that opinion if I noticed that the oil was still clean and good at 1000km.

I change the oil in my ancient Triumph at about 1500km and its usually well ready for a change by then but it runs a good filter and holds 3litres.

Your bike may have an issue or two so I would change it more regularly than if it was new. As the engine wears its likely to pollute the oil a bit more hence the 1000km suggestion. End of the day its your bike and you can change it whenever you like or never if that suits too - its not bothering me a jot.
Brown oil isn't such a problem, it's just the detergenty things in it working and holding carbon. Oil that looses it's viscous and lube properties is the worry. I'd be very interested to see somebody getting theirs analysed at 1500km, 3000km and 5000km and see what's actually happening.
You're right though, regular oil changes are good and on a GN it's still cheap as chips (I run Motul 3100 or whatever that mineral oil is called, always had good luck with Motul)

If your GN is like my original motor, it'll use so much oil you'll always have clean stuff in it :laugh:

[FJRider]

.. If your GN is like my original motor, it'll use so much oil you'll always have clean stuff in it :laugh:

In 5000 km's ... it's probably "used" a liter of oil ... it doesn't stay in the motor long enough to get dirty ... :laugh:

I once did a Chatto Creek 1000 mile rally (1635 km's) ... it used 8 liters of oil ... :blank:

[ducatilover]

In 5000 km's ... it's probably "used" a liter of oil ... it doesn't stay in the motor long enough to get dirty ... :laugh:

I once did a Chatto Creek 1000 mile rally (1635 km's) ... it used 8 liters of oil ... :blank:
Mine was managing around 1L/100km :D :devil2: