Right then, done a search but not come up with much so i thought I'd see if anyone can point me the right way, many thanks if you can!

The problem was noticed the other night when the bike started to slow down and missfire like it was running out of petrol (full tank of fuel). Bike stopped and was very hard to start, dying shortly after if it did get going. After abandoning it in the middle of nowhere managed to get it retrieved the next day. I have sinced checked exhaust temps after getting it going in the garage, front pipes are scolding, rear left is luke warm and rear right cold, though i can only reach bit's that are further away from the head due to the frame.

Anyway checked the plugs and all 4 are pretty caked in oil, threads oily, and the bit where the washer lives. Ran out of time last night but changed the two rear plugs for new ones and after 5mins of idling came out oily again. With a smidge of white smoke out of exhaust.

Recently (probably done less than 100miles since) done valve clearances, carb jetting and clean as per guides on here. Bike was 89 spec but now has 118/120 mains. It ran really well through the revs, no more flat spot but i did notice slight missfiring after a while but assumed battery issue (which was on it's last legs, new one in now). But obviously just got worse with this damned oil.

So is it either piston rings, valve seals, or other? What do i test next? Don't have a compression tester but don't mind buying one if it's gonna help. Next thing ive been suggested is to swap the coils over, which could explain why rear exhausts were cold but not the oil on all 4 plugs. Also minor point, oil level on dipstick is at max, but this is cold, which i now realise could be overfilled, but by much?

Sorry for length but trying to give as much info as possible, thanks again for reading. Any help apreciated as we have a hot date booked at the 'ring in september and don't really want to be stood up :D

Ha didn't realise this was my first post.. Been lurking for a long time :D so also... Hello.

Can you get a picture of the actual plug tips up?

oil on the threads around the ceramic isnt the end fo the world.. it could poitn to a leaky rocker box gasket though letting a small amount of oil drip into the plug area. If youve had the top off recently it might not be sealing right.

Anyay.

Start with the obvious.

Run the bike first and check the electrical system, i.e voltage output, this can cause all sorts of shit running and look like carbs.

Next get the plugs out and check you have a spark on all 4 by cranking the bike with the plugs out and held against the engine / frame.

Right oh yes I'll start from the basics then but here is a picture of the front right plug when I took it out. Doesn't look like any oil on ceramic part.

SmallFrowne wrote:Right oh yes I'll start from the basics then but here is a picture of the front right plug when I took it out. Doesn't look like any oil on ceramic part.

That looks normal actually. but what about the tip (electrode part) thats where the burn happens.

It doesnt look wet but does look black.. should be a nice tan / grey if its not over-rich

Hi, yeah that looks ok to me, there prob a bit sooty from idling, maybe worth checking the valve crearances again to make sure all is well.
Nc30 plugs die very easily, never try just reving it up quick and stopping it, the plugs will wet up and stop sparking, if your going to run its make sure you geting it warm and preferably a quick ride is always better.
Is it smoking loads especially on the overrun?
Cheers
Ian

Do you have fuel flow, vacuum hose and fuel tap diaphram all ok?

Thanks for the replies. Just had another go at it, checked voltages at 5.5k rpm as per RO's guide, which was quite hard keeping it there due to the misbehaviour, really didn't like being above idle.

The reading across the battery was between about 5.9v and 7 and a bit. Which didn't look too great. According to the guide this could indicate 2 bad coils. Time for more searching and probably get a pair of coils then, but is there any other reason for a bad voltage reading, or why 2 coils could pack up at once, like a bad reg/rect?
Cheers

And yeah, fuel seems to be getting to carbs ok, and comes out of the tap ok when I've got the tank off the bike

Something is very wrong with your charging system.

You need to inspect it fully.

http://www.electrosport.com/media/pdf/f ... iagram.pdf