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I believe there was a thread a while back regarding an independent mechanic and his differing opinion from that of the BMW manual on breaking in these engines.

I ran across this website and I am not sure if others have seen it or not but I found it quite interesting. Thoughts/Opinions?

http://www.mototuneusa.com/break_in_secrets.htm
 

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SACM5 said:
I believe there was a thread a while back regarding an independent mechanic and his differing opinion from that of the BMW manual on breaking in these engines.

I ran across this website and I am not sure if others have seen it or not but I found it quite interesting. Thoughts/Opinions?

http://www.mototuneusa.com/break_in_secrets.htm
Bad advise......this article is about snowmobiles and motorcycles.

High engine loads are very detrimental & even dangerous, when clearances are tight on a fresh, modern motor. New BMW motors run bearing clearances under 0.001", in some cases down to 0.0005"!!! This is a great way to ruin a motor by spinning a bearing or destroying a piston or fragile, fresh alusil cylinder wall. The recommendations given are suitable for a fresh, 1960's-vintage dirt track motor, snowmobile or motorcycle with loose clearances.

The recommendations in this article are focused solely upon ring seating issues and ignore greater lubricity & hardware concerns. Fresh BMW motors are way too tight to follow this formula.
 

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Lscman said:
Bad advise......this article is about snowmobiles and motorcycles.

High engine loads are very detrimental & even dangerous, when clearances are tight on a fresh, modern motor. New BMW motors run bearing clearances under 0.001", in some cases down to 0.0005"!!! This is a great way to ruin a motor by spinning a bearing or destroying a piston or fragile, fresh alusil cylinder wall. The recommendations given are suitable for a fresh, 1960's-vintage dirt track motor, snowmobile or motorcycle with loose clearances.

The recommendations in this article are focused solely upon ring seating issues and ignore greater lubricity & hardware concerns. Fresh BMW motors are way too tight to follow this formula.
Just remember that current STREET motocycle technology is WAY ahead of even the V10 in the E60, including the use of tight clearances, microfinished bores etc. Even the new K1200S BMW motorcycle gets 170HP out of 1200CC! and it's by no means a class leader in BHP/Liter. The only tech in the e60V10 that's not made it to M/C is the vanos technology, which really isn't a clearance or break in related issue.


My personal experience with M/C engines and break-in supports his theories. I didn't use this for my M5 as it came to me with 3K miles and showed all signs of being babied. My car runs well, but is oil thirsty to the tune of 1 ltr/1500miles after 69K on the odo.
 

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I've heard this advice before from people who apply it to all engines, even cars. I refuse to accept it over the guidelines of BMW in Germany, which I followed with all by BMW's and only the M burns oil. Having read every posting on this subject, I do not believe oil usage is related to the break in process. I have one of the first M5s to enter the states, and after 8400 miles oil consumption has dramatically decreased (as BMW said it would, 10-15K miles). Also, I do not believe that the ring change in 2000 addresses oil usage, as newer models can burn a lot also.
 

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on my 00 M5 (6.00 production) i typically use no oil, i can get 2500-3k miles without adding any, with normal street driving. It seems that after i hit the 3k mile mark, oil consumption goes up. This also happens after a track weekend. I assume that the oil is breaking down and that is causing it's increased usage. I'm using 10./60 tws.
Mike
 

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mottati said:
on my 00 M5 (6.00 production) i typically use no oil, i can get 2500-3k miles without adding any, with normal street driving. It seems that after i hit the 3k mile mark, oil consumption goes up. This also happens after a track weekend. I assume that the oil is breaking down and that is causing it's increased usage. I'm using 10./60 tws.
Mike
Same behavior in my '03. I change oil every 3000 miles (also Castrol TWS 10W/60).

I also test my oil at every change (at Blackstone Labs). I've been meaning to present some data based on 18 months of running the car and testing the oil.

I'll try to get it posted sometime in the next week or so.

Jeff :cheers:
 

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Jessem said:
My personal experience with M/C engines and break-in supports his theories.
For the record, my personal experience with motorcycle engines and break-in supports his theories too! These ideas are not new. You buy a Husaberg with Nikasil bore or Asian high performance bike...& ring it out mercilessly with zero miles! M/C engines are simply different. They are not more advanced than BMW car engines and they require different break-in techniques. If you want rings to seat better, break-in your motor on cheap, thin oil and hope you don't spin a bearing. Opportunities to improve ring seal are basically over after 5K miles & better lubricants impede break-in. The problem with the M5 ring seal is likely related to insufficient tension. To make matters worse, the ring wear surface may be too durable and resistant to break-in with high quality synthetics. It is challenging to build a motor to meet so many goals.
 
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