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   Strange clunk/knock, 85' K100RS Empty Strange clunk/knock, 85' K100RS Sun Nov 03, 2019 3:38 pm

kjott

kjott
New member
New member
Does someone have a clue what this sound could be?

This is not the actual bike, but is has the same clunk/knock when idling (and small reving) with the revs dropping a bit.

 

    

2Back to top Go down   Strange clunk/knock, 85' K100RS Empty Re: Strange clunk/knock, 85' K100RS Sun Nov 03, 2019 4:04 pm

charlie99

charlie99
VIP
VIP
output shaft rivet issue ?


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

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
1987 k100rs ########   "Red"  - (red sports rs TWB style )
1989 K100rt #009637   "Black Betty"  (naked rt ala Nigel , now sporting an rs main fairing )
    

3Back to top Go down   Strange clunk/knock, 85' K100RS Empty Re: Strange clunk/knock, 85' K100RS Sun Nov 03, 2019 7:58 pm

Laitch

Laitch
Life time member
Life time member
It sounds to me like intermittent weak spark in one cylinder. That's what I'd hope anyway, if it were my moto's engine doing this. Laughing  I'd check the coil terminals and clean them, check the HT leads and clean them, check the plug terminals and clean them then compare the spark plugs to each other. Diagnosing the condition of one engine by listening to the noise made by a different engine doesn't seem like an effective strategy though.


__________________________________________________
1995 K75 90,000 miles
    

4Back to top Go down   Strange clunk/knock, 85' K100RS Empty Re: Strange clunk/knock, 85' K100RS Mon Nov 04, 2019 5:03 am

Stumpy

Stumpy
Silver member
Silver member
Try using a screwdriver and put it on different parts of the engine until you find the area that the sound is loudest. That will give you a starting point.


__________________________________________________
BMW K100RT 0095857
    

5Back to top Go down   Strange clunk/knock, 85' K100RS Empty Re: Strange clunk/knock, 85' K100RS Mon Nov 04, 2019 9:54 am

moriarti

moriarti
Life time member
Life time member
Hi for just a few pounds/dollars you can buy a Stethoscope on ebay, one of the handiest tools to have, noise finder/carb seter ect.And you can check your heart rate to make sure your still here Strange clunk/knock, 85' K100RS 723598


__________________________________________________
1984 k100 rs red/black VIN  0004449 Now sold to Olaf
    

6Back to top Go down   Strange clunk/knock, 85' K100RS Empty Re: Strange clunk/knock, 85' K100RS Mon Nov 04, 2019 3:35 pm

kjott

kjott
New member
New member
Thanks for the reply's, but this is a bike I'm thinking about buying, so I dont have it in my garage :/

The video under is of the actual bike. Some knocking and small drop in the revs. Could a bad breather hose and bad sync make this? (I know the hose had a small leakage).



    

7Back to top Go down   Strange clunk/knock, 85' K100RS Empty Re: Strange clunk/knock, 85' K100RS Mon Nov 04, 2019 7:19 pm

volador

volador
Platinum member
Platinum member
How many thousand miles/kilometers on the moto?
Has the moto sat for some time neglected?
The owner have any maintenance history?

If you see the Z shaped crankcase breather hose is cracked, inspect the intake manifold rubber stubs, plenum/air accumulator rubber bushings and throttle body protection caps if original may all be suspect of leaking

Moto probably just needs a tune up and some new rubber


__________________________________________________
1984 K100RS  1991 K100RS  Reap The Wild Wind... Ever Commute Is An Adventure
    

8Back to top Go down   Strange clunk/knock, 85' K100RS Empty Re: Strange clunk/knock, 85' K100RS Tue Nov 05, 2019 6:48 am

Dai

Dai
Life time member
Life time member
Sounds like leaky rubber to me, combined with the possibility of a partly-blocked injector. Nothing insurmountable, just a little time-consuming. See Volador's list.


__________________________________________________
1983 K100 naked upgraded to K100LT spec after spending time as an RS and an RT
1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

Sponsored content


    

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