My NC30 likes drinking a bit of oil.

I change the oil every 1500km's and at about 1000km's the gearbox starts misbehaving, like I have to give it a firmer kick to get it into 2nd sometimes, and not sliding into neutral without revs. I know this isn't a problem but I find that I have to top it up at about 1000km's.

Anyone else the same?

Maybe you need to look at changing the piston rings?

Maybe, tad expensive and time consuming at the moment though, plus I have no space to strip the bike.

Plus it's only done 28k km. Not many miles really.

No oil usage here, also, oil stays extremely clean for prolonged periods compared to other engines from my experience.

Hmm, I'll post a picture up of my oil next time I do a change.

You've got me a bit curious about the history of my engine now....

yep never had one that uses oil. not a good sign.
be cheaper to buy a good used motor from someone here and change it over. to be honest you will break even after 3 years with the saving in burned oil lol.

Hmm, further inspection definitely needed then.

Are there any signs of it going anywhere? If it's leaking to the point you're running low, the stuff will be everywhere. My 35 has a very minor weep somewhere that leaves the engine and inside of the fairing a little more oily than I'd like, yet it doesn't notice at the dipstick, so if yours is showing as being low, there'd probably have to be a lake of it in the fairing. Does the engine smoke? Surely burning enough to need topping up after 1000Ks would show up at the exhaust and/or cover the plugs in crap?

It smokes quite a bit when on choke, but that's probably condensation or sumat.

I'll take a much closer look when I do valve clearances and stuff after christmas as I'll have the bike stripped down to frame engine fork and subframe.

It'll be getting a thorough scrubbing too, so I'll be able to see anything recurring after it's back on the road.

If its leaking there should be at least some spots under where its parked.

Gear shaft oil seals do go, as well as the rocker-box seals and sump drainer so start with those. the gearbox one will need cleaning as it will most likely have chain shit all over it.

Its an old bike so probably had many UK owners and who knows how many Japanese owners.

Unless you have every UK MOT then there is no guarantee of the mileage, and even then many dodgy imports would alter the mileage before selling them back in the day.

Mileage on these bikes isn't really so important anyway as long as they are looked after.

To say it has only done 28,000km (18k miles) doesn't really mean a lot, after all it only takes probably as little as 1km for a muppet to cause damage to the engine.

Both my 24 and 30 don't use any oil, well any measurable amount between changes (5000km / 3000 miles) and never have to put any more in but do check it weekly.

Maybe youll get luckier out of the possibilites and its a leaking rocker box or something, but it sounds like a worn engine.

Compression test is a good start before ripping it to pieces.