Running very badly, 2/3 cylinders.

[NC35]

It sounds like the big end bearing has gone on one of your con-rods. If it is, you'll be far cheaper looking for a replacement engine rather than thinking about overhauling that one.

[theonefromthesky]

I tend to agree, does sound like a big end failure. Althought I must say its not common for these to have issues, must have been run a little dry in a previous life otherwise these engines are bulet proof!

From experiance, big end failure often "ovals" the journal so much so that its a wasted effort re-grinding as you would be unable to buy big end shells up to tollerance, depending on extend of the damage your rod may be able to be saved, but would need checking for trueness before even considering re-using. Then you need to find out why it failed, as a precaution I would replace the oil pump and all other big ends/mains as well. And if it has run dry/low on oil, the cams and caps are likely to be scored to as it farthest from the oil pump, so that woudl definatl need some looking at!

As sugested, it will be cheaper to source a new engine as oposed to fix this one oil starvation causes so many unseen issues its not worth the bother!

Jody

[joshmolloy]

Calm down dears, it was a cam follower pivot shaft, which hadn't been replaced properly after inspecting under rocker cover, having slid to one side when re-assembling.

New plugs are on order. Didn't want to spend the money but it's daft worrying about big things when it could be something so simple.

Thanks

[theonefromthesky]

Damn, you spiled my fun. I love finding complicated solutions to simple problems!

Although I once had an issue with a cam follower.... the rocker arm fell on to the cam drive gears in the middle of the front cylinders. lucky it didn't cause the engine to seize up. Unfortunatly becasue the rocker fell out it meant that the shim fell in to the depths of the engine (never did find it) and the valve cotters came loose so the retainer and spring fell out, which subsiquently bent a valve. the strange thing is, is that the only reason I realised it happend is for a strange "rubbing" noise comming from the engine, the rocker arm on the cam gears. The fact that the valve had jamed itself closed meant the bike still started and ran fine....

Jody

[NC35]

That's a result - and a helluva lot cheaper than a replacement engine!

[joshmolloy]

Yeah dead chuffed! Still waiting on plugs. This bike might still be a bargain!

[joshmolloy]

Plugs came, it goes. I am very happy!