Classic symptoms of dodgy valve stem seals. My 88 bike was exactly the same. From cold, 10 seconds of smoke then no smoke at all and very little oil usage. Depending on your level of competance with the spanners, a relatively easy fix. no need to take the engine out, but you will need a valve spring compressor.

Thanks for the advice, I'm glad I'm not alone with reading the oil levels, yes I do intend to get out there and enjoy trouble free ridding, the bike is new to me I intend to keep it so just making sure all is well.
Thanks again

Thanks Timus I'll see what happens after a few more rides, yes I do have a good workshop

I thought you said it was high mileage ???? PAH !! :rofl:

anyway.

Smoke on start up is most likely stem seals.

If it smoked all the time I'd be thinking it was the rings.

Done a compression test ??

More likely to be oil draining down into the sump overnight, once the engine is started it's then pumped back to the tank....

What, you think that is causing the smoking on start up?

Surely if there was a way for oil to get up past the rings it would smoke all the time?

usually....

But, the rings and piston do expand a little when they're hot.

I'm still going to valve seals.

It's an easy job on this engine too. It's the first logical thing to try.

Valve stem seals shouldnt be bad after such "short" time. It sounds a lot like a classic overfilled bike, which you seem to have veryfied yourself. Poor in the right amount of ail, drain/clean the airfilterbox and see if that doesnt help, if not, take it from there.

I cant read a full oillevel when my oil is 60C, especially not with theese cold temps, a good run on the highway usually does it. I've had my bike for around 4 years, and have driven around 65.000km on it, and everytime I try to top of the oil 'cause it seems low, I end up overfilling it. They are a PITA tocheck the oil on, mine doesnt use any, but with 116.000km on it I get nervous and check it often, but usually it reads low, eventho' the correct amount of oil is in it.

I had an 87 XT600...

It did EXACTLY the same thing when I bought it.

Depending on how the valves rested when I turned off the engine, occasionally oil would weep through the seal and into the cylinder. Some days it didn't do it as the valve was completely shut (lucky).

I changed the seals and it sorted it....

You've only got four valves in there and the seals aren't too expensive. It's a simple job. And at that mileage it should be something you should of been considering changing anyway.



If it was the rings, it would most likely be smoking all the time. If it was overfilled, the crankcase breather (if you have one) may be spitting oil.

I agree with Ted.
My 88 bike did the same thing, til I changed the valve stem seals.

Never had any issues with oil level.

It's definitely hard to get a consistent oil level reading, more so when draining/refilling. Each bike seems to be different, but for mine I get a consistent reading by

1. Ride until fully warmed up, at least 10 minutes
2. Let it idle for 10 sec or so
3. Wait about 3-4 minutes for the oil to settle
4. Check level with bike upright

This is most easily done when stopping for fuel. Fill the bike, go and pay, and check the oil level when you get back. I keep a bit of kitchen roll handy somewhere for wiping the dipstick.

Until I learned to trust this method, I have previously drained out around 3 litres and then refilled with a whole 4 litre can, and still had nothing on the dipstick. Of course, it all went in the airbox until I drained it out and started again.

With the above method, I have had a completely consistent reading for the last 15k miles - it drops about 5mm between oil changes. I'm happy with that.