1 Starter issues – K100RS Sat Dec 21, 2019 4:40 am
GeoffP63
active member
1985 K100RS (55,000 ks)
BEP 3.0 with Acewell 2853 speedo
Neutral light is active
Hi all,
My apologies for this long post but I wanted it known that I have given this problem a lot of time and effort before coming here for assistance.
There is an abundance of information on this subject and although I have followed the advice from numerous posts from Robmack, RicK G and Holister to name a few, the problem below persists.
Bike started & ran perfectly prior to rebuild.
When pushing the start button the starter initially gets power (starter relay clicks but motor will not turn over.)
I can hear the starter engage and can see the alternator move slightly, confirming it is moving the engine.
The starter relay appears to be getting power initially (+12v to control coil terminals) but won’t hold the internal contacts closed to allow it to turn over.
This was confirmed when I removed the cover from the starter relay.
+12v to starter relay from rear terminal (to battery), +12v from front terminal (to starter motor) when start button is pushed.
When I manually close the internal control contact point the motor turns over strongly until I release it.
This happens irrespective of whether the ignition is on or off or if the kill switch is in the run or stop position.
On a few occasions it did turned over but then continued turning until I removed the earth lead.
Aware that the starter relay might have been damaged by an undercharged battery, I installed a new starter relay and new fully charge 290 CCA battery, problem persists.
Another observation, although may not to related ;
When the ignition is turned on and the headlights switch on, lights remain on when the kill switch is in the run or off position and remain on when the start button is pushed, although do flicker when start button is pushed (I assumed the Load shedding relay should turn it off?) Someone can hopefully confirm if this is normal behaviour.
Checked Load shedding relay with +12v (Internal click) and Multimeter confirms ok. Swapped Horn & load shedding relay anyway
Tested load shedding relay – jumper from starter motor connection to ground whilst ignition on and kill switch in run position (did not push starter button :blush:)
If lights are switched on when doing the above, lights stay on.
What I’ve done so far;
- Brand new fully charged 290 CCA battery
- Checked all battery connections are clean and tight
- Neutral light is working on new speedo, also confirmed Clutch switch is working
- New starter relay
- Checked starter motor – cleaned commutator, brushes well within spec, bench tested with direct connection to battery
- Start button/kill switch – Thoroughly cleaned all contact points and checked for continuity
from start button to wiring loom and to relays
- Cleaned and checked ignition switch
- Checked and cleaned all earth points on frame
- Unplugged every connector, including under tank (not used Deoxit yet)
- Removed all relays, cleaned contacts
- Checked all fuses
Any help or suggestions would be much appreciated.
Regards,
Geoff