Right, I have now officially run out of warranty. The good news is that I don’t have to worry about overworked KTm mechanics who really don’t know what they are doing some of the time. I have had a noisy engine since day dot. (not to mention numerous other well documented hassles) Recently I have has some oil issues too. Twice I have been really on it for extended periods and when I stop and do an oil level check just for peace of mind my oil level has been way over full when I know that for hundreds of kilometres before it has been sitting where it should? The clatter has been getting progressively worse and all the numerous threads on cam chains and cam chain tensioners prompted me to send the bike in for a last time to try get rid of the clatter under warranty. The noise if I try to define it sounds like cam chain clatter from both front and rear cylinders coupled with something very faint, more of a ticking up near the front cylinder head. Personally I was pretty sure that maybe the chains were stretched. The best they could do was replace the cam chain tensioners and apparently prod and poke and give the bike back with no apparent change in noise level. The mechanic said that he had been advised to by KTM to use a heavier oil but didn’t have any in the shop. He said he was advised to use Shell Helix 60 weight oil. Oil developed for older engines. To me this was a cop out as all it was going to do was mask the symptom. But what can you do? So, off to our vacation house and yesterday I decided to go and see if I could get hold of any of the oil he was talking about a try an oil change myself. The shop had some, so back to the bike, checked the filters and changed the oil, put the left tank back on and started her up. At first it sounded much better but as the temperatures bars went from zero to 4 bars the racket got worse than before!? It really didn’t sound good at all. Even my wife who knows nothing about bikes commented that it was very loud. I felt like taking it out on a ride and making it an insurance problem. After a bit of a search on the net, looking for KTM 950 and Shell helix I came across this post; http://www.advrider.com/forums/showthread.php?t=44817&highlight=helix Taki had experienced exactly the same symptoms as me! This got me to thinking that I must have some sort of pump/oil problem and this problem had now been exasperated by the heavier oil. Checking through the shop manual at the section on servicing the oil pumps – which would be a bitch to get to as you have to split the cases to get to both of them – I noticed the next bit has a part on servicing the oil bypass valve. This valves function is to keep the oil pressure “with engine at operating temperature (oil temperature 100ºC in oil tank) between min. 0,8 bar at 1500 rpm to min 2,4 bar - max 3,5 bar at 6000 rpm. Also the spring has some tolerances; Bypass valve Length of spring, unloaded min. 41.5 mm Spring tension 27 mm at a load of at least 3.5 kg As I didn't take photo's, this is the manuals shot of it. The slot below to the left is where the oil screen goes and the major bearing above is where the clutch would be. Aha! So, I phoned the mechanic told him of my findings and asked him about this valve. He knew about it and said that there was a factory order to change the piston on some of the earlier models and that it was possible to get to the spring if the clutch cover was removed. He said that as I had just filled the bike with new oil, instead of re-draining the oil that all I had to do was lay the bike on its left hand side and work from there. It requires the front exhaust header be removed and the coolant is drained before you start. Once this is done, you don’t need to take the pump impeller off to get the clutch cover off. You don’t need to take the outer clutch cover off either it can stay bolted to the main clutch cover. As the bike is lying on its side getting the circlip and the washer that sits behind the spring without dropping it into the engine is almost impossible without a shop cloth stuffed under the valve and into where the oil screen sits. Getting it out needs right angled pusher circlip pliers that can reach at least 3cm. You cant get the piston out as it won't clear the case before it is completely clear of the tube it sits in. My spring was 40.52mm. I stretched it to 47mm and put it back. Putting it back was a mission of note mostly as there is not much space and it requires 2 more pairs of hands. All I can say is hold the pliers tight and use the circlip and a finger to push the whole story home. I buttoned everything back up filled the coolant and ran it up to 4 bars. It seemed to be great and it was a lot less noisier. I went for short 50k ride. It is much quieter, not as quiet as some I have heard but a vast improvement on what I had before. Also the ticking has gone. But a big bonus is that it is noticeably stronger by far. My beast is back. So, it could be that the Bypass spring gets tired and this is the cause of a lot of the pressure hassles that manifest in a variety of ways from cam chain and tensioner issues to over full oil tanks. I would rate the check as a 2 on a scale of 5 as to difficulty to fix and requires the following if you lie the bike on its side; Circlip pliers Antifreeze Torque wrench for the clutch cover bolts. Shop cloth Patience.