KTM 640 Horrible engine noise!!!!

Yes the seals are there, but you may have to replace the shaft if it shows a wear ring on the sealing surface...

Just to let you know my finding. The head Mechanic from KTM here in Dublin rang me to call into him today so he could show me the damage and wear that had caused my noise and metal that was found on the sump magnets. He was concerned when I had dropped it in and I had told him it had broken the teeth on the starter gear so that where he headed for first to investigate. Turns out all my noise is caused by the starter clutch assemble and fly wheel. There is a lot of wear on the starter clutch and it's relivent components. The clutch itself should only spin one direction but turned both ways and there was wear on every thing else so he's replacing the whole starter clutch assembly and I'll have it back Friday.

Hope your finding aren't to bad.

It will probably now need a flywheel or some machining on it to get the gouges out.. surpised the sprague would not have disintegrated

Fly wheel is been replaced with a new one.

Probably gonna ditch the starter motor on mine, so no worries if it is the cause

You might want to check out this thread...lots of similar talk to your problems...

Go to:
http://www.advrider.com/forums/showthread.php?t=118095&page=3

and on to page 3...





Hope this helps, as my friend left his bike to me with similar issues this week.

My money is on a spun crank bearing.

Looks like bad scoring, but you can't even feel it!

Do those roller bearings on the rockers have any play in them?

Sideways play in the rollers, no up/down or twist.



Guessing the stator cover doesn't seal very well! :huh

You been losing coolant?

Nah, but I will be rebuilding the pump.

Stuck now, need flywheel puller, spanners for the base bolts, and a large flathead screwdriver for the chain guide...

Your cylinder looks better than mine.
bill

If it's the same further down I won't get it plated. Maybe a new piston? If all I'm changing is the big end bearing then I may splash out on either a nice piston or the rally cam...

Looks like I got there just in time, plating measures well, and can't feel any damage. Piston is starting to wear so will replace that. Just gotta wait for my flywheel puller to turn up (****ing Sundays!!).

Definitely what I would call 'too much play' on the big end.

Any advice on splitting the cases?

So, the bill so far,
£65 - Electric Impact Wrench
£18 - Electric Screwdriver (so fed up with twist,ratchet,twist,ratchet,twist)
£80 - Athena Gasket Set
£22 - Flywheel Puller

And will be purchasing
£136 - Pro-X Conrod Kit
£140 - Wossner Piston Kit
£60-80 - Crank Rebuild


So far is £448, will be rebuilding the water pump too... sigh.

yup...all of them sound like a can of bolts rattling around. And they do a funny thing while idleing on the stand...they move!



Moto_psycho, how are the valves?

How do you mean? I am yet to remove, lap and change the seals, need to borrow the spring compressor off of my Dad tonight.

How might I go about measuring the bore for piston size? Wossner have 3 sizes 0.01mm different, I know that is fuck all, but what clearance am I measuring here?