Fixing excess oil consumption in 2000 R1100S

[spacewrench]

I just did a 3800-mile, largely high-speed loop around the US southwest, and went through about a pint of oil, maybe a pint & a half.  Bike doesn't leak (no drips after standing, and not even much oily grime on the bottom of the engine).  I don't notice blue smoke, but I don't spend much time looking for it, either.  I guess it's burning the oil.

Is there anything I can do to fix this?  Even if it's not that terrible or unexpected, it makes me feel like a bad bike owner every time I notice that the oil level is down to the bottom of the sight glass.

[Paul De]

Nah, a bad owner would not check the sight glass and only act if the oil light came on.   I think the Oilhead motor generally consume some oil, more rare that they use none.  I think my R259 motor consumes similar amount of oil and I just top it up once between oil changes at 3K mile intervals.  Not sure if getting to no oil consumption is feasible on this motor...maybe using the center stand VS side stand, but that prolly makes no practical difference either.

 

As a side note my Waterhead motor pleasantly shocked me in that it appears to use nothing between oil changes, even during the break-in miles.

[dirtrider]

1 hour ago, spacewrench said:

I just did a 3800-mile, largely high-speed loop around the US southwest, and went through about a pint of oil, maybe a pint & a half.  Bike doesn't leak (no drips after standing, and not even much oily grime on the bottom of the engine).  I don't notice blue smoke, but I don't spend much time looking for it, either.  I guess it's burning the oil.

Is there anything I can do to fix this?  Even if it's not that terrible or unexpected, it makes me feel like a bad bike owner every time I notice that the oil level is down to the bottom of the sight glass.

 

Afternoon  spacewrench

 

That really isn't terrible oil consumption, especially if you were riding long distances at high speed. There a lot of 1100/1150 owners that wished they only burned a pint per 3800 miles.

 

Most of the time the oil consumption on the BMW 1100/1150 engines is due to incomplete piston ring sealing due to the extremely hard cylinder walls. Once the cylinder walls glaze a little it is very difficult to get them to not burn some oil.

 

With the high speed (ie high RPM,s) you might find some of the oil in the bottom of the air cleaner box. The early 1100S had a drain valve on the bottom of the air box but I don't believe the later 1100S has that drain.

 

[Cap]

On 5/1/2019 at 11:36 AM, dirtrider said:

 

...incomplete piston ring sealing due to the extremely hard cylinder walls. ...

 

 

This explanation, which is well founded, is nevertheless unsatisfying.  I get really hot when BMW Motorrad service managers tell me in a patronizing tone, "They all do that, sir."  What they won't tell you is that some oilheads burn a lot more than others.  And they are really vague on how to ensure that your moto becomes one of the latter and not the former.  

 

I have owned one of each: a 2001 R1150GS that I bought new, and which burned a lot of oil -- a quart every 1000 miles or so.  I currently have a 2004 R1150RT that I bought used with 16k miles, and that burns half a quart every 3000 miles.  So, what's the difference?  

 

I imagine we all have theories why some oilheads burn more oil than others.  My speculation, which applies only to my GS, is that I goofed when I was breaking in the engine.  I switched to synthetic oil after about 3000 miles.  And maybe I didn't place enough load on it while the rings were seating?  All speculation.  My used RT has service logs showing regular dealer service during the 12 years before I bought it -- so I am pretty sure they used BMW branded oil.  Of course I have no idea how it was used during those 12 years -- other than to note that 16k miles in 12 years suggests infrequent use.

 

So, what can you do if you have a low-mile oilhead that burns a lot of oil?  My choice was to sell the GS before the warranty expired, and to be forthright about it with the new owner.  DR might weigh in on this ... I suppose you could always disassemble the engine, and hone the cylinders and replace the rings, and then break it in again.  But the labor cost of that process would be high.  Oil is cheap.  

 

Most of my riding is long-distance touring.  I find that high oil consumption is more than a nuisance.  I won't keep a bike that does that.

 

Cap

[spacewrench]

2 hours ago, Cap said:

I suppose you could always disassemble the engine, and hone the cylinders and replace the rings, and then break it in again.  But the labor cost of that process would be high.

I'd be interested to do it for the education... Maybe I could upgrade to 1150 jugs at the same time?  I suppose that would require new heads too, and pretty soon I'll find myself hobbing my own primary gears. 

[Cap]

6 hours ago, spacewrench said:

I'd be interested to do it for the education... 

 

Actually, it sounds like you have one of the good ones.  Enjoy it.

 

 

[BrianM]

On 5/5/2019 at 12:49 PM, spacewrench said:

I'd be interested to do it for the education... Maybe I could upgrade to 1150 jugs at the same time?  I suppose that would require new heads too, and pretty soon I'll find myself hobbing my own primary gears. 

It can be done, I did it.

 

The 1150 piston skirts have to be machined so as to not contact the crank. Same heads will work, but the locating dowels are smaller for the 1150 (same center). Need to make stepped dowels. Think that was all - did it a while ago.

[spacewrench]

On 5/9/2019 at 2:48 PM, BrianM said:

It can be done, I did it.

 

The 1150 piston skirts have to be machined so as to not contact the crank. Same heads will work, but the locating dowels are smaller for the 1150 (same center). Need to make stepped dowels. Think that was all - did it a while ago.

Looking at the specs, that seems like a lot of work to get an extra 2mm of bore, 44.3cc, and (maybe?) lower compression.  Any reason to do it besides "I can"?

[tallman]

That is not a lot, in BMW world of boxers.

What we found, was most of the time, oil "burners" were babied during break in.

Not always, usually.

High speed, high rev, distance, helped, usually.

 

BMW used to have a "spec" wrt oil consumption.

X per 1000lm.

It was a lot of oil, IMO.

None of my boxers burned much oil.

So little I quit carrying my small oil container that I topped off with.

There are outliers, babied  non burners, rode like I stole it that burn.

Once ypu figure out what your bike does, live with those parameters.

And, the old Italian tune up is good for the bike and the rider.

Best wishes.

[BrianM]

18 hours ago, spacewrench said:

Looking at the specs, that seems like a lot of work to get an extra 2mm of bore, 44.3cc, and (maybe?) lower compression.  Any reason to do it besides "I can"?

 

I had the heads off because I had damaged a valve (got it double plugged at the same time). It burned more oil than I would like, San Jose BMW sold an 1150 "kit". So I did it mostly because I could. Not sure how much it helped. Probably not worth the effort for the average person (I have access to a machine shop and can do my own machining). It really didn't help with oil burning either. The double plug did greatly reduce surging.

[Whip]

I ride an 1150 GSA.

 

The heavier the oil the less it uses.

 

20/50 and it doesn't use any.

 

10/40 and I gotta add oil all the time.

 

 

 

 

[Miguel!]

On 5/1/2019 at 10:36 AM, dirtrider said:

 

Afternoon  spacewrench

 

That really isn't terrible oil consumption, especially if you were riding long distances at high speed. There a lot of 1100/1150 owners that wished they only burned a pint per 3800 miles.

 

Most of the time the oil consumption on the BMW 1100/1150 engines is due to incomplete piston ring sealing due to the extremely hard cylinder walls. Once the cylinder walls glaze a little it is very difficult to get them to not burn some oil.

 

With the high speed (ie high RPM,s) you might find some of the oil in the bottom of the air cleaner box. The early 1100S had a drain valve on the bottom of the air box but I don't believe the later 1100S has that drain.

 

Just a follow up, my R1100RT burns about 1 pint every 1500 miles. I spoke with my mechanic about it. He says that's about normal. He has been working oilheads for 10+ years and services the CHP and local police bikes. Most of the police bikes I've seen at his shop have 150-180K miles and he says they still have lot of life in them. 

 

Best

Miguel

[spacewrench]

2 hours ago, Whip said:

20/50 and it doesn't use any.

 

10/40 and I gotta add oil all the time.

 

That might be part of it -- I think I was running Rotella T6 5W40 on that trip.  I just changed to Mobil 1 15W50 for the summer, so I'll see if there's any difference.  (Maybe I can free up enough time for a ride back east...for Science!)

[Paul De]

I think that BMW recommends the heavier oil at all temps above 40 F (I think) for the R1100 motor, but with 20W50 dino oil at 40F it is already hard cranking on a cold start up.