Some help required..

[john1000]

Hi again,

Brought my bike back in September, and has run all through the winter flawlessly, up until last few weeks..

Usually, what ever the weather, the bike would start straight up within a second of hitting the button. But odd times lately it just refused to start - so i leave it for 30 mins or til the next day and then suddenly starts again.

So thats not that bad... but i was going down m25 last week and suddeny i lost half the power and engine sounded very different, I suspect it was only firing on 2 or 3 cylinders.

Anyway, thought id check out the plugs and leads, whilst taking the plugs out for a check it appears there is oil all over them at the bottom of them ( where the plug sparks). i have checked and oil has NOT leaked from the rocker cover and down through the thread - i mean oil must be mixing with the fuel/air to get on the plugs there.

What do you think this is? i managed to start it today and all 4 cylinders are firing but power is a bit down, engine just dosnt seem right.

THanks

[RedexRobB]

Could be a couple of things but are you sure its oil and not fueal?

if its oil, its either leaky valve guide seals or the piston rings but that would have caused you serious problems by now.

[john1000]

Hi Rob - thanks for the reply.

Deffo is oil, and i think this explains the ball-ache starting lately! i dont think piston rings as still have good compression, other bikes ive had have lost all compression when a rings blown!

any more info on this : leaky valve guide seals ?

Searched the site but all im getting in valve clearance info!

Regards

John

[john1000]

had a good look this morning, seems theres oil now leaking over the case - head gasket ? oil looks normal though and coolant hasnt noticeably leaked, is it just starting to blow? its done 14k miles.

[RedexRobB]

If you have good compression id have thought that the valve guide seals would be ok. What pressures have you got for compression?

If the oil on the front of the motor looks like its coming from under the headers then it will more than likely be the seal for the plug recesses. It leaks out and down through some holes next to the plug which come out under the headers. Any oil shouldnt be making its way into the head from there.

[john1000]

Hi Rob, had the compression tested last week, all was 110-130psi - however its running worse now.

i run the bike this morning, and it started OK but got hot very quick, the fan kicked in within a few mins of sitting still. thats when i noticed the oil - seems to be coming out of where the head attaches to the below engine case. deffo not just under the header pipes either, as pic 3 shows oil coming from opposite side of engine too.

im hoping this is the head gasket or another gasket since ive taken the motor out now - will be able to look at it proply tomorow.

Any other ideas what it is ?

Thanks for the help.

[RedexRobB]

Those are headgasket symptoms to be fair, but compression says otherwise. Thing is its usually the coolant which gets in and fouls the plugs, not oil. Has the air filter been oiled recently?

[john1000]

No, it hasnt been oiled! is that a big problem? put it on about 2 months a go. so i guess that could mean that dust ect has got in the engine ?

[RedexRobB]

It needs to be oiled when put in new, I ask because the oil can be sucked in with the air, but I dont thinks thats why you have oil on the plugs.

Im sure theres a particular way the compression needs to be measured, might be worth checking that out and make sure its been measured properly, but heating up so quickly after just a few minutes, plugs fouled and its running poorly really points towards a head gaset if you ask me. Only other suggestion would be theres oil getting in the fuel from somewhere and could be why it runs bad, but im sure we can discount that one.

[john1000]

Thanks for all he help Rob. Will have the compression tested again next week with a screw-in adapter and also change head gasket, is there anything else I could do whilst the motors out? Apart from a check on the tappets.

Thanks,

[RedexRobB]

can check the cam chain length and and the cam chain guides while its apart Other than that not much else to check.

[gazza]

on the head the gasket is the oil leaking all round ?? could be a oil mixture to rich

[john1000]

seems only from left side of engine casing. and what you mean oil being to rich? id understand if we were talking 2 strokes..

Going to open it up this weekend and take another compression test, have a look around and then change head gasket.

Thanks

[john1000]

Can anybody give me a really quick rough guide of whats involved to do the head gasket? ive got the engine out so should be easy to work on. surprised i couldnt find a guide on how-to do it on here,

Regards

[john1000]

just an udpdate;

was headgasket after all



THanks rob for help.