BMW K bikes (Bricks)

You are not connected. Please login or register

View previous topic View next topic Go down  Message [Page 1 of 1]


1Back to top Go down    Increasing oil level on Thu Apr 02, 2015 12:58 am

Point-Seven-five

avatar
Life time member
Life time member
Changed the oil in my K75RT last winter. Filled so that after a bit of running the level was about 3-4mm below the top of the circle on the sight glass, figuring it would drop from there.

Took the bike out and put 110 miles on it a couple weeks ago. It ran well and appears to have normal fuel mileage. Was working on the bike this evening and noticed that the oil level is now touching the top of the circle on the sight glass. There doesn't appear to be any milkiness indicating water so I am thinking I may be getting fuel in the crankcase.

Anyone know how that might be happening? And where to look for the source? All I can come up with is an injector that isn't sealing off completely and allowing some of the pressurized fuel in the rail to leak into the intake port. But how does it get from there to the oil if the intake valve isn't open? I could see it on an old engine with a mechanical fuel pump having a diaphragm leak. But on these engines the fuel and oil are pretty well isolated, aren't they?

Is it possible that I just had a bubble in the sight glass?


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

2Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 1:17 am

Bigsax

avatar
Gold member
Gold member
Was it on level ground both times?

Did you use the centre stand both times?

If fuel is getting in there you should be able to smell it, or drain a bit and see if it burns.


__________________________________________________

I stole this image, let me know if you want it back.
    

3Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 1:53 am

RicK G

avatar
VIP
VIP
I have found it takes a very small difference in angle of the bike to make the level in the sight glass change. I think this is because the sump doesn't sit central on the bike it is offset to the left and so if the bike is leaning a bit more to the right than when last checked it can appear that the level has increased quite a bit. Also once the oil level gets to the centre of the sight glass the same volume of oil added has a bigger effect on the level than it has at the lower part of the sight glass because internal components start to be immersed.
I ever only fill to the centre of the sight glass because of the parking on the sidestand and smoking the whole district out problem. The bricks do it even though the factory pinned the rings, my K1100 is very good at it.


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

4Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 2:43 am

Point-Seven-five

avatar
Life time member
Life time member
To answer the question of the stand and parking. My bike has sat in the same spot in my garage on a concrete floor. I always park it on the centerstand and this is where I check the oil. The only difference I can think of is that since changing the oil I replaced the original K75 centerstand with the straight leg K1100 centerstand to make it easier on my back to get it up on the stand when I park.

The stands may be different, but the height of the rear wheel looks very similar, so I don't think the geometry of the parked bike has been substantially changed.

I think I will be taking a bit of oil out tomorrow. I am interested in how much it actually takes to raise the level that amount, and I want to see if I can smell any gas in the oil.

As far as my question, I an hoping someone else has seen this and has an idea of how the gas if any is getting in there. Or if indeed it's possible to have an air bubble in the sight glass that causes it to read low initially after an oil change.

In any event a little oil is coming out tomorrow and I will be reporting what it smells like.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

5Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 3:26 am

RicK G

avatar
VIP
VIP
If the inlet is open and the exhaust closed it will leak past the rings.
Be glad it isn't like my Z1300 Kawasaki, if the fuel is left on and a needle and seat in LH carb leaks it fills the crank cases then up the breather into the air filter then out onto the ground and with a full cylinder a conrod will bend when you try to start it. I think every owner has had all but the bent rod happen a few times before you remember to turn the fuel off.


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

6Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 3:38 am

Point-Seven-five

avatar
Life time member
Life time member
Exactly what happens to my tractor when it's parked. Fortunately, the starter isn't strong enough to damage anything. It just locks at tdc. Have a fuel shut off on it now.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

7Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 7:25 am

rosskko

avatar
VIP
VIP
@Point-Seven-five wrote:to make it easier on my back to get it up on the stand when I park.


I think I will be taking a bit of oil out tomorrow. I am interested in how much it actually takes to raise the level that amount, and I want to see if I can smell any gas in the oil.

Or if indeed it's possible to have an air bubble in the sight glass that causes it to read low initially after an oil change.

In any event a little oil is coming out tomorrow and I will be reporting what it smells like.

I have an 1100 and a 100 and the 100 is way easier to get on the centre stand. Just my opinion. I believe technique plays a greater part than any stand configuration.

It is not possible to have an air bubble. Behind the sight glass is a backing plate (probably to give a reflection or reference point or some crap) and it is open on the top, sides and back (holes drilled).

It takes very little oil to go from 'almost there' to 'crap, overfilled' when looking through the glass.

How fuel would get in there? No idea.

Good luck getting "a little oil" out. Loosen sump drain plug.... a bit more....a bit more.... just one mo....crap it is in the pan and all the oil is coming out...put a finger on it... where is the...may as well do an oil change now. Smile

Maybe the long weekend and beer is making this funnier in my head, but it sure beats watching football


__________________________________________________
1986 K100RT VIN 0093801K100RT with summer fairing for a northern visitor

Basic/2 6308802K100CJ05/1988

K1100RS 0194321
    

8Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 8:01 am

92KK 84WW Olaf


Life time member
Life time member
Rossko,

What sort of coffee are you drinking there? It's not Irish coffee is it?


__________________________________________________
1992 K100LT 0193214 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 83,150miles
    

9Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 8:18 am

Born Again Eccentric

avatar
Life time member
Life time member
@Point-Seven-five wrote:The only difference I can think of is that since changing the oil I replaced the original K75 centerstand with the straight leg K1100 centerstand to make it easier on my back to get it up on the stand when I park.

The stands may be different, but the height of the rear wheel looks very similar, so I don't think the geometry of the parked bike has been substantially changed.
.75,

I also changed my centre stand to the straight leg version last year (June 2014):

http://www.k100-forum.com/t8174-centre-stand#95612

As detailed in the post at the time, my increased difficulty in getting the bike up onto the centre stand was due to lack of grease and badly worn bushes (note to self....go and get grease gun on those centre stand nipples and give em a good squirt of grease again...today! Post-note to self: Bushes now greased on side and centre stand, job done!)

I didn't notice any change in oil level...but I wasn't looking. I tend to keep my oil level at the top of the sight glass (with bike on level ground and on centre stand), topping up as required between oil changes. However, I have noticed that the ground clearance between the rear tyre and the ground has reduced a little (about 2 - 5 mm). Not that I measured it before and after, it's just that the rear tyre is now only just clear of the ground, whereas before it was sitting noticeably higher. This suggests that there is a slight difference in the way the bike sits between the two types of centre stand. I haven't a clue what the geometry of the internals of the engine oil chambers is like, but think it is entirely reasonable that even the slight changed induced by changing the centre stand is enough to give you a small change in oil level in the sight glass.

To be getting significant amounts of fuel into the oil sump would mean both your injectors and piston rings (and even your timing/spark plugs) are behaving badly and you will be able to smell the fuel when you do your oil change. Personally, I think this is unlikely. Likewise, if it is water causing the level rise - you will see emulsification of the oil.

My money would be on the side stand differences - do your oil change, reset your oil level in the sight glass and monitor to see if it remains steady (or very slowly drops with use).



Last edited by Born Again Eccentric on Thu Apr 02, 2015 8:43 am; edited 1 time in total (Reason for editing : Updated note to self)


__________________________________________________

Paul

"Heidi" K100LT 1991 (Grey) (VIN 0190172 Engine No. 104EB 2590 2213) - 5th owner. January 2014 (34,000 - 61,000 miles and counting....)
"Gretel" K100LT 1989 (Silver Grey) (VIN 0177324 Engine No. 104EA 2789 2211) - 4th+ owner. September 2015 (58,500miles and counting....). Cat C Insurancewrite-off rebuild Feb 17
"Donner" K100LT 1990 (Red) (VIN 0178091 Engine No. 4489 2024) - 6th & final owner (crash write-off now donor bike). June 2012 (73,000 miles) to November 2013 (89,500 miles)
    

10Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 8:48 am

Point-Seven-five

avatar
Life time member
Life time member
First, regarding centerstands. I have both a 4v 100RS and a K75. It wasn't until I got the RS that I saw how it is a bit easier to get the bike up on the newer stand. Can't attribute it to grease as I had both lubricated. I suspect it has to do with the geometry of the contact point and how much the bike is being lifted as the stand is deployed. I agree that the clearance below the rear wheel looks to be slightly less. At the weight of these beasts, even a few mm less lift can be felt in my back.

Hoping not to have to do a complete dump of the oil as what's in there now only has about 110 miles on it and is essentially brand new. It's too bad BMW had to baffle the filler so I couldn't use my dipstick oil change pump to bring the level down. I know it's going to be messy, but I don't think I'll have to dump the lot of it. Might only have to put in a few ounces to get the level right.

Not going to spend too much time on it. Today is forecast to be sunny and warm for the first time this year. I going for a ride!


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

11Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 9:05 am

Ringfad

avatar
Life time member
Life time member
Minimum level (bottom of the ring)
Maximum level (top of the ring)

Capacities between Min/Max approx. 0.6 litres (1.05 pints)

From the riders handbook
This might be of some help


__________________________________________________


;BMW;K100RS Style Black 1987 99K Km ;BMW; K1 Black 1993 42KKm ;BMW;K1100RSRed 1993 50k miles
    

12Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 10:54 am

Two Wheels Better

avatar
Moderator
Moderator
The last several years or more BMW have been recommending oil level consistently be checked on an engine that's been running a few minutes, switched off and level, such as on the main stand when so fitted, due to the appearance of fluctuating oil levels.


__________________________________________________


'77 R75/7-1000cc, '87 K100RS, '93 K11/K12 Big Block, '94 R100R Mystic, '03 K1200GT, '04 R1150RT, '06 K1200R & '07 K1200R
    

13Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 11:51 am

brickrider

avatar
Life time member
Life time member
I too have experienced fluctuating oil levels. I've changed oil, run the bike some considerable distance and, upon rechecking the level thought the engine was consuming a bit of oil. Next day the level was back up to where it had previously been.
I just love a machine with character! Very Happy

    

14Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 12:12 pm

Two Wheels Better

avatar
Moderator
Moderator
My '87 RS has always done that, so I never fill it more than a smidgen above the oil sight glass' bottom. Afterall, there are 3.something litres in it at that level, and the level will be at the middle a day or two later.

A longtime BMW mechanic I worked with years ago, and who favoured K's (he had an '85 with over 200,000 miles on it fifteen years ago), once told me "There's a lot of places for oil to hide inside that lump of a motor".


__________________________________________________


'77 R75/7-1000cc, '87 K100RS, '93 K11/K12 Big Block, '94 R100R Mystic, '03 K1200GT, '04 R1150RT, '06 K1200R & '07 K1200R
    

15Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 3:44 pm

Point-Seven-five

avatar
Life time member
Life time member
Sounds like 4-5mm changes are no big deal. Is that right?


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

16Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 8:55 pm

RicK G

avatar
VIP
VIP
If it keeps producing oil then store it in big barrels and wait for the price to get to $110 then sell and flood the market Laughing


__________________________________________________
If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

17Back to top Go down    Re: Increasing oil level on Thu Apr 02, 2015 11:04 pm

K75cster

avatar
Life time member
Life time member
I'd expect if you put the original stand back on the oil would return to the same place it was when first put in.


__________________________________________________
Keith - 1987 K75c with r100rt replica fairing and half of a 1984 K100rt

The Clever are adept at extricating themselves from situations that the wise would have avoided from the outset - QUOTE from david Hillel in Out of the Earth.
    

View previous topic View next topic Back to top  Message [Page 1 of 1]

Permissions in this forum:
You cannot reply to topics in this forum