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1Back to top Go down   K100rs electric problem is baffling me ! Empty K100rs electric problem is baffling me ! on Wed Jul 09, 2014 8:37 am

LSAXB02

LSAXB02
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Hi, My K100rs is having electrical problems. The dash lights come on , when you hit the start button  the injectors squirt fuel but doesn't fire  the starter  -  no lights , indicators , horn etc - but i can bump start the bike and she runs well !!!!!!  changed the alternator and that has made no difference , i see on some posts the ICU could be playing up - or has anybody got any other suggestions please ? Battery is fairly new and have tried jump leads from another battery and  still nothing.    Thanks - Adrian.



Last edited by LSAXB02 on Wed Jul 09, 2014 8:39 am; edited 1 time in total (Reason for editing : extra info)

    

92KK 84WW Olaf

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A few things will come up but I am not the right one for it.

Load shed relay.
Starter relay.
Starter motor brushes/cleaning it.

All easy to check. If all the lights etc go out when you press the starter than that to me suggests load shed relay is working properly, its supposed to disconnect them all. Starter relay worth a check and so are the earths. One above the gear lever, some under the petrol tank, easy to get at.

I had issues like yours, so I cleaned out the starter motor and got it like new. Easy to get out and to sort and its worth doing anyway.

The ICU up at the headstock turned out to be my problem. I got a replacement from Motorworks for £50 and it cured the problem. However it could have been a dodgy connector to the ICU as opposed to the ICU itself. When I got the replacement I cleaned all the connectors until they were nice and shiny and connected it up, problem finally solved.  So its worth taking out ICU and cleaning up the connectors but be gentle.


__________________________________________________
1992 K100LT 0193214 Bertha Alaska 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 105,200 miles
1983 K100RS 0011171 Fricka 606 29,495 miles Damn K Pox Its a Bat outta Hell Now 36,188  miles
    

RicK G

RicK G
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Check the brushes in the starter. when they wear down they don't have enough pressure to make a high current connection.
Careful to mark the starter case so it goes back together with the correct alignment, if you get it wrong it will spin but the wrong direction.


__________________________________________________
"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 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

LSAXB02

LSAXB02
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Thanks Gents !  that has given me few pointers for the next couple of evenings ! The starter is coming out and all connections i can find  cleaned ! i won't give up !!!  i will report back. cheers   Adrian.

    

92KK 84WW Olaf

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I would do the starter anyway as its an easy one.

Before you go at it you might be able to check if the relay is working, if you hear a click when you press the starter button. If it does click then its probably [always only say probably] ok and its getting a signal which is probably good news and go for the starter. Careful about marking it too so it spins the right way. If you haven't done it before you will see the two Allen bolts at the rear, and the power supply on top. It just wriggles back towards the rear wheel as you pull out it out of the casing, there is an o ring seal on the end of the shaft which comes out with it. You need the coil cover out of the way and that's pretty much it. I found it worth moving the battery for wriggle room but others here manage fine without moving the battery.

I used 1200 grade wet and dry to clean it up so it was nice and shiny for a good electrical connection with the brushes. Used dry. Doesn't take too long to do.


__________________________________________________
1992 K100LT 0193214 Bertha Alaska 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 105,200 miles
1983 K100RS 0011171 Fricka 606 29,495 miles Damn K Pox Its a Bat outta Hell Now 36,188  miles
    

k75RT Keith

k75RT Keith
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Silver member
+1 for cleaning the starter.  Simple, fast and inexpensive repair that removes the most common point to reference for starting problems. 

IMHO, the biggest issue with these confounded K's is that almost every mechanical failure of the electrical system is tied to dirty grounds or a dirty starter and it seems the place where most folks with problems don't want to start their repair/diagnosis at.

    

orforester

orforester
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+2 for starter brushes, cured my similar problem.  Install new ones, don't bother cleaning.


__________________________________________________
89 K 100 RS se
85 K 100 RT
    

LSAXB02

LSAXB02
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Gentlemen,   thank you all for your technical advice , the bike is now  running perfectly with a replacement STARTER MOTOR !! i extracted the old starter and when hooked to a battery it turned over  but slowly and it prompted me to go on e-bay and purchase a £19 replacement! This was delivered and when hooked to a battery it turned over so fast i knew i was onto something ! The bike started first click and all electrics are working fine. The replacement starter is old and noisy so the next thing on the list is a brand new starter or a  rebuild of the original.(does anybody know a good rebuilders ?)   The bike was washed just before its MOT this morning , passed without issues and she had a quick blast on the M25 to work where she is happily sitting in the bike park . Once again thanks for your help. Adrian. Very Happy

    

Inge K.

Inge K.
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K100rs electric problem is baffling me ! 112350  Congrats.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

k75RT Keith

k75RT Keith
Silver member
Silver member
Rebuild the old starter.  Taking it apart and replacing the brushes and cleaning the contact points is very simple.  I am not a wrench and I can do it.  Big trick is to mark the case and 1 end cap so you put it back together the same direction it came apart.

    

Inge K.

Inge K.
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@k75RT Keith wrote:Big trick is to mark the case and 1 end cap so you put it back together the same direction it came apart.

The rearmost end cap.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

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