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1Back to top Go down   Pinned rings in '87 K75 possible?? Empty Pinned rings in '87 K75 possible?? Fri Aug 24, 2012 1:26 am

robmack

robmack
Life time member
Life time member
Hi,

Just a question out of curiosity. I have an 87 K75 which smokes if left on the sidestand for any length of time. I know this model predates the change by BMW which pinned the rings to prevent the ring gaps from lining up and allowing oil to seep into the combustion chamber (08/88).

Is it possible to replace the rings or pistons on the early models with pistons / rings from later models to eliminate this behaviour? If so, which is it -- just rings / just pistons / both? Is it a straight forward job or is it a labor intensive job?

Thanks for satisfying my curiosity.


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Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

Rick G

Rick G
admin
admin
Rob my 93 K75 smokes if left on the side stand and it does have the pinned rings. When it does it every bug within shouting distance starts coughing and choking.
I really don't think there is a solution. I have heard that leaning them over to the right as soon as they stop will minimize it but I try to park on the center stand as often as possible.


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"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1986 K75 GS.
    

Ghost who rides

Ghost who rides
Life time member
Life time member
The pinned part is the piston and said pins prevent the ring end gap being (presumably ) at the bottom of the bore which could lead to oil seeping through the gap . This is common practice on two stroke engines but in that case it's to avoid the ring end catching on a port .
I wouldn't think it worth the trouble if you have a good running bedded in engine and as Rick says his '93 model smokes anyway !
Strangely my '86 sometimes does but mostly not , or perhaps i don't always look ?

    

Two Wheels Better

Two Wheels Better
Moderator
Moderator
This hot topic always makes me curious. My late '86 K100 doesn't smoke, unless I start it from cold and almost immediately stop it and park it on the sidestand...because I've left my house unlocked or can't find my earplugs or any number of brain-fading reasons...then start it up again within minutes...but not always.

I recall at rallies in the '80s and '90s (when I rode Airheads exclusively) that almost every K left a vapour trail as they buzzed away just after start up, and, as Rick suggests, left mossies (and other campers) in coughing spasms. On some group rides only a few of many will smoke, and not always dependent upon the year or (mile)age of the bike.

I always try to use my centrestand. It avoids embarrassment when it does decide to have a cig. But at 26 it's old enough to smoke.


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1970 R60/5, '77 R75/7-R100, '85 K100'87 K75C, '87 K100RS, '93 K11-K12 Big Block, '93 K1100RS, '95 R100-Mystic, '96 K1100RS, '98 K1200RS, '00 K1200RS, '02 K1200RS, '03 K1200GT, '04 R1150R'04 R1150RT, '05 K1200S, #1 '06 K1200R, #2 '06 K1200R, '07 K1200R, '09 K1300GT, '13 R1200RT-P & 2022 S1000XR

"Do you ever read any of the books you burn?" "That's against the law!" "Oh, of course."
~Ray Bradbury, science-fiction writer (22 August 1920 - 2012)
    

rosskko

rosskko
VIP
VIP
It has been so long since my bike was even on a stand that I had forgotten if it smoked. So I tried it.
All I needed was some essence of 2 stroke and it would have been like I was back at Amaroo Park watching the Mr Motorcross series back in the 70's. Go Stephen Gall.
Center stand for me from now.

rossco


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

Basic/2 6308802K100CJ  05/1988

K1100RS 0194321
    

charlie99

charlie99
VIP
VIP
remember those days well rossco ....awsome maicos and huskys and bultacos too ...then the jap invasion hit hard, had a mate that used to do club days on the road circuit, that smell of that racing fuel and oil was awesome

old gerty smokes well ....often after i plonk her on the sidestand whilst still running ...i found if i turn her off ....and wait a little while before leaning ...8 out of 10 times no smoke


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cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OPinned rings in '87 K75 possible?? Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

7Back to top Go down   Pinned rings in '87 K75 possible?? Empty Re: Pinned rings in '87 K75 possible?? Sun Aug 26, 2012 10:33 pm

robmack

robmack
Life time member
Life time member
Thanks for the discussion guys. Funny thing with my two bike is that the side stand for the K75 hardly causes the bike to lean at all whereas the K100 is nearly at a 60º angle. Still, the K100 never smokes and the K75 smokes at the slightest provocation. I guess I'll try some of the suggestions made here -- lean to the right after turning off to let the oil drain back to the sump, put it on the centre stand rather than the side stand, and let stand vertically after shutoff.

The short answer is leave well enough alone. No need to break into the engine to do a major pistonectomy as the prognosis is poor that the symptoms will disappear.

Cheers.


__________________________________________________
Robert
1987 K75 @k75retro.blogspot.ca
http://k75retro.blogspot.ca/
    

K75cster

K75cster
Life time member
Life time member
It would be cheaper to build another propstand for the right.


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Keith - 1987 K75c with r100rt replica fairing and half of a 1984 K100rt 1992 K1100LT a blue one

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.
    

Themason

Themason
Gold member
Gold member
One reason for smoke is oil spray off the output shaft gear getting into the rearmost cylinder. Oil level has an effect on this. Don't fill above the center dot in the sight glass on level pavement.


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I live in a parallel universe but have a vacation home in reality :arrow:

1984 K-100RS Alaska Blue w/Parelever and 16V wheels.

1984 K-100RS Metallic Madison stock

1986 R-80G/S w/1000 cc engine

2007 Harley Davidson Street Rod Mirage Orange w/XR1200 wheels, Race Tech, True Track, Works Performance shocks

2007 Harley Davidson Street Rod Vivid Black stock

1993-ish K-100/1100RT/LT hemaphrodite frankenbike thingy to be painted satin black from a rattle can eventually
    

10Back to top Go down   Pinned rings in '87 K75 possible?? Empty Re: Pinned rings in '87 K75 possible?? Thu Nov 29, 2012 3:54 am

92KK 84WW Olaf

avatar
Life time member
Life time member
I have 101,000 miles up.

I am using prop stand most of the time but I always kill the engine and remove gloves before dropping it onto the stand.....I get no smoke on start up. But I generally straighten it up and paddle backwards out of the garage before firing up. I am sure at 101,000 miles it could smoke a pipe but I see none.

I can only presume both of these actions mean no oil remaines in the bore on the udnerside of the piston or between the piston and the cylinder wall.

Either way its a case of dont worry, its not worth stripping the engine to stop it happening as it does not look like a defect.

92KK


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1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011171 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 49,840 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 42,640 miles.

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

11Back to top Go down   Pinned rings in '87 K75 possible?? Empty Re: Pinned rings in '87 K75 possible?? Thu Nov 29, 2012 5:45 am

klompy the grey brick

klompy the grey brick
VIP
VIP
K75cster wrote:It would be cheaper to build another propstand for the right.

Now that is thinking outside the square......profound my friend.

I often wonder why left hand drive countries have left hand side ...side stands??


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KKlompy Pinned rings in '87 K75 possible?? 2854237993
"Grace" 1984 K100RS Silver VIN 0019026 Mitt eine Staintune Zorst.
"Olivia" 1997 K1100LT Dark Grey VIN WB1052600W0237453.









Chassis number0019026
Vehicle code0503
SeriesK589
ModelK 100 RS 83 (0502 ( 0503 )
Body typeK 100 RS 83 (0502
Catalog modelECE
Production date1984 / 07
Engine0513)

Pinned rings in '87 K75 possible?? Au-log10


    

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