Thread: 08 450 EXC the oil problem

Could really do with some help here please.

I have an 08 450 EXC-R and have just started getting the oil transfer problem, gearbox to engine. The bike also smokes like hell after a downhill descent on closed/partial throttle or if it has been leaned over on the lefthand side (as you sit on the bike). It's definitely oil as its blue/grey smoke but it burns off within a few seconds of riding on the flat. It's only just started doing this but obviously it needs sorting, question is what is the likely cause? I'm assuming an oil seal has failed somewhere allowing oil to flow from the gearbox and the downhill angle combined with additional oil is forcing oil past the rings and it's then being burnt off - does that sound correct?

There's no noticable drop in performance so I don't think the rings are shot and the last value check (at 92 hours, now on 106) all values were spot on, albeit right at the minimum gap. I've read loads of conflicting stuff about these motors but hoped someone on here might point me in the right direction and offer any advice as to modifications and/or third party replacement parts that solve this problem.

Any help/advice would be very much appreciated.

The best advise I could give would be sell it on ebay and buy a 2 stroke.

Measure your oils first.. to find out if it is moving across or just burning engine oil.

If I remember correctly its 600mm engine and 900mm gearbox. Dont over fill the engine, I think I used to put in 500mm or so at each change and get 450mm out everytime. Gearbox next changed quantity.

Mine was an 08 450 exc-r.

The best advise I could give would be sell it on ebay and buy a 2 stroke.

Was kind of hoping for something a bit more constructive

It is definitley transfering oil. Checked engine oil at about 3/4 of the sight glass and gearbox oil just running out of oil level hole behind rear brake lever. After a days run then leaving bike overnight before rechecking oil, the engine oil well over the glass and gearbox needed top up, I reckon about 100ml. It is also burning a bit as I described, this occurs after a downhill, especially on closed/partial throttle, cloud of blue smoke which clears after a few seconds of riding on a level surface.

Any ideas?

Change the crank seal to the newer version (you will be supplied newer version even if you order an 08 part)

Thanks for the help Kev, much appreciated.

Read this and all might become clear.

Board Message

Thanks to you all for the advice and especially for the link brompton92. Ordered the 08 part and got...the 08 part so ordered and fitted the later seal from the 2010 model, which appears to have done the trick. When I drained the oil there was just over a litre in the engine and about 300ml in the gearbox plus some swarf on the drain bolt magnet and in the gauze filter, fingers crossed it's not knackered the gears or bearings - it sounds and rides fine so far....

The original seal had split into two parts, the face of the seal literally feel out when I touched it leaving the seated part in the crankcase; this came out ok though. Topped up with the correct oil quantities and quick blast round the block and no oil transfer, so fingers crossed I'm done.

Thanks again for the help/advice.

Originally Posted by JFoz

Thanks to you all for the advice and especially for the link brompton92. Ordered the 08 part and got...the 08 part so ordered and fitted the later seal from the 2010 model, which appears to have done the trick. When I drained the oil there was just over a litre in the engine and about 300ml in the gearbox plus some swarf on the drain bolt magnet and in the gauze filter, fingers crossed it's not knackered the gears or bearings - it sounds and rides fine so far....

The original seal had split into two parts, the face of the seal literally feel out when I touched it leaving the seated part in the crankcase; this came out ok though. Topped up with the correct oil quantities and quick blast round the block and no oil transfer, so fingers crossed I'm done.

Thanks again for the help/advice.

carnt believe a ktm dealer sent you the old 2008 single lip seal out instead of the duo, doh comes to mind