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David246
Jul 27th, 2007, 8:07 pm
has anyone changed to synthetic oil in the engine before 12000 miles

gunny
Jul 27th, 2007, 9:55 pm
Yup

At 6K went to synthetic. No prob.

cfell
Jul 27th, 2007, 9:58 pm
at 600 mile service.

beartooth
Jul 28th, 2007, 12:24 am
Went to synthetic at 7K in May this year. Just returned from 2200 miles to and from the MOA in WI and didn't use any oil that I can detect. They are factory filling cages these days with synthetic oils, including Bimmers. I think we need to put to rest the myth of dino oils and engine break-in. The only recommendations for special break-in oils seem to be in the aircraft industry. Must be something unique about the metals involved in cylinders and piston rings. I do know that aircraft cylinder walls are tapered (like a choke on a shotgun) and expand to parallel when fully warmed up. I yield to someone with more knowledge who can explain the differences.

Bruce '05 LT :)

JATownsend
Jul 28th, 2007, 8:23 am
Went to synthetic at 7K in May this year. Just returned from 2200 miles to and from the MOA in WI and didn't use any oil that I can detect. They are factory filling cages these days with synthetic oils, including Bimmers. I think we need to put to rest the myth of dino oils and engine break-in. The only recommendations for special break-in oils seem to be in the aircraft industry. Must be something unique about the metals involved in cylinders and piston rings. I do know that aircraft cylinder walls are tapered (like a choke on a shotgun) and expand to parallel when fully warmed up. I yield to someone with more knowledge who can explain the differences.
Bruce '05 LT :)
I can't speak to the aircraft cylinder walls, but as far as the reference to 'Bimmers' goes, the cars have different liners that the motorcycles.

BMW motorcycles have 'Nikasil' liners. BMW cars did away with them some time ago.

http://en.wikipedia.org/wiki/Nikasil
http://www.go-lpg.co.uk/Nikasil.html
http://www.gunsmoke.com/motorcycling/k75s/k75s_living.html

These are very hard and have proven to take a good amount of break-in. Many do not go to syn until after 12K or even 18K. It seems as though the slipperiness of synthetic oils impedes the rings ability to seat against the hard Nikasil.

Now, I don't want this to digress to "An Oil Thread" so, BMW does not recommend the use of syn in their bikes until oil consumption levels off. Then "Fine!" :bmw:

That very often is different bike-to-bike and rider-to-rider, as break-in methods or the lack thereof, then to vary.

My recommendation would be to keep a sharp eye on your oil usage and make the call when you see reduced oil usage.

I changed at 15K. Of course, YMMV.