Turned on the K75S this morning...plenty of battery charge, but not turning over...happened once last week, but ended up starting after a rest. What's with that then...,??

Does the neutral light come on it the cluster?

Have you tried pulling in the clutch?

If it's not turning over then the first thing I'd check is that power is getting to the black/yellow wire that triggers the starter relay when the start button is pressed.

Thanks for the pointers!
Yes, all the lights are on including neutral when key is turned. Pull clutch in, start, but no turnover. It does get power to the starter motor, but it feels like it gets "stuck"....I'll did out the multi meter!!!!!

If you can hear the starter motor "trying" then it sounds like the starter relay is getting power and working.

You might want to consider cleaning or replacing the starter motor.
https://www.k100-forum.com/t2342-starter-motor-cleaning-tutorial

Clean the motor's brushes.  They might need replacement.

double check the EARTH near the starter.

Try turning the motor slightly by moving the bike in gear, sometimes the starter seems to have little dead zones. Mine's done it a couple of times, really weird!

As per .75 clean and check the starter brushes.
Regards Martin.

spin the starter backwards on a regular basis to keep the brushes clean

1-sit on your moto in 3nd gear or higher with key off...
2-roll backwards and pop the clutch...
3-repeat 4 or 5 times...
4-do this a few times a year...

The roll back brush cleaning works to a point, but eventually you'll need to pull it apart and clean it properly. It takes around about an hour to do it and you get the added benefit of checking the brush length.
Regards Martin.

I’ve just taken mine out for a clean and re-brush - it was mucky and the brushes were just on their wear limit - so glad I did it and it couldn’t have been easier.

A little wet and dry on the gearbox mounts is prudent and I also added a secondary earthing wire while I was there.

A bit of Kopper Kote around where the starter housing slides into the bell housing is prudent. A mate had to slide hammer his out due to corrosion.
Regards Martin.

MartinW wrote:A bit of Kopper Kote around where the starter housing slides into the bell housing is prudent. A mate had to slide hammer his out due to corrosion.
Regards Martin.

I had the same issue when I took starter off the RT first time.

As for brushes, brush set is available and is cheap. Anyone having a few Ks its worth keeping on in the shed....

Charged battery, and cleaned out starter motor. I did the brushes last year, so it was in good condition inside.
Starter relay next on my list....

Opened starter relay...cleaned the contacts...put everything back together....tried starting...initially, the same mild kind of klunk, but then, turned over and started! Needed a bit of cranking to get going. It’s been so damp here....moisture in everything...so I wonder if that was it......I’ll keep an eye on it.....nothing I hate more than an intermittent electrical fault!!!!!

Yep...there it is again!!!

I haven’t checked yet, but I’m wondering if the alternator brushes may be the cause of this??

n/m. The idiot behind this keyboard should try reading what you've written.

So, what I have is:
1) 12.47 volts at the battery (Odessey pc680)
2) Turn key to on position, and all dash lights come on as they should. Clutch in, push starter, and then the lights cut, (so load shed must be working), but the engine does not turn over. Lots of clicks from relays etc.
3) My logic to this moment is:
- there is enough power in the battery.
- power seems to be getting through to the starter, which has been cleaned, and the brushes checked.
- Rocking bike back and forth in gear, and then attempting start makes no difference.
- The starter switch seems to be doing its job.

4) Questions are: is the voltage regulator to blame? Can't test this till I'm running again. Is the battery suspect? I'll take it out again and charge for a while and see if that makes any difference.

Wisdom welcomed, and I also acknowledge that this post should be in the electrical forum slot! 

12.47 too low for the battery....

Next time you are at it......

1: record meter reading at rest before you try starting.
2: record meter reading when starter button is pressed.
3: record meter reading when bike is running. 

Post them up but my thought is battery issue, its possibly being caused by poor charging OR a parasitic drain/short.

Alternator brushes maybe?
Can I jump start from a slave battery to test this?

BooG wrote:Can I jump start from a slave battery to test this?

I'd follow Olaf's suggestion in Post #20 on this. It's a simple test series to diagnose a common fault

 
A "fully" charged 12V battery that is more than a year old with less than 12.8VDC on it is frigging bad and needs to be replaced! 

A battery with 12.47V on it when resting will not reliably start an engine and will sooner or later need replacing.  Why are you wasting your time with this battery?  Get a good one before doing anything else to remove electrical power issues from your problem.

Even if the problem is in the charging system, the fact it is not fully charging the battery will result in irreversible damage to the battery's ability to get a good charge that will properly start and run the engine.

So:
12.9v at rest...
7.2v when switch is pushed (under load)
starter does not turn over.

I put the meter on the starter motor live and tested it under load, and it only read 4v..!
So, given that most people are inclined towards the battery....its another Odessey PC680 tomorrow!
All other functions seem fine: good lights/horn OK, etc....just won't crank!

I hope you have some hair left.... point 75? 

Cue ball.

I assume you are reading at the battery terminals.  Battery voltage on my bikes drops to about 10 VDC when the starter is cranking.  The voltage you are reading tells me the plates in your battery are toast.

Thanks for the help...I'll sort a new pc680 tomorrow and see what happens. Luckily there is a battery warehouse in Enfield, not far from me (Hackney), so I'll pick one up in the morning (£100)...! Not actually that bad for a pc680..

If you can't get an Odyssey for any reason then a Motobatt AGM is the next best thing.

Well, she's up and running, and the odyssey is cranking that engine like it should! Thanks guys....I'm never looking to spend £100 on a fix, but sometimes you just have to suck it up and go there!! I love the forum!!
It was intermittent, but I checked the battery terminals at 2000 rpm and it was putting out about 13.8v, so alternator seems OK as well. I'll keep y'all posted! 

BooG wrote:Thanks for the help...I'll sort a new pc680 tomorrow and see what happens. Luckily there is a battery warehouse in Enfield, not far from me (Hackney), so I'll pick one up in the morning (£100)...! Not actually that bad for a pc680..

On Friday I found that's whats in my K1100LT!

Well now....this morning I had that same starting issue! The new Odyssey is only a few weeks old! 
Gonna change the alternator brushes out. The logic is:
The issue disappeared with the new battery initially. 
Assuming the new battery is sound, then the alternator may not be throwing enough charge into the battery...although when I put the meter on it a few weeks back, it was charging 14v+ when revved. 
I'll charge up and report back.

If the alternator is working and you get good DC volts across the battery, then have you check for parasitic drain when the engine is switched off?

It could be that it is draining the battery a bit overnight, causing the poor starting in the morning.

Mike

mike d wrote:If the alternator is working and you get good DC volts across the battery, then have you check for parasitic drain when the engine is switched off?

It could be that it is draining the battery a bit overnight, causing the poor starting in the morning.

Mike

Put a meter on it, it will show if you have a parasitic drain.

If you have, pull the fuses one at a time and watch what happens as you take out each fuse. 

If you still have a parasitic drain pull the relays one at a time carefully watching what happens as you pull each relay.

That will tell you what circuit is your problem. Or it if its a faulty relay.

If you still have a parasitic drain pull/disconnect the Regulator...it can also cause one.

I had a wonky voltage regulator that left me stranded and bump starting the moto until changed

13.2 volts....still not turning over! Power to the starter motor, but just won't spin that sucker...sort of clunks like it originally did. So: enough juice in the battery...power all the way up to the starter motor..but not turning over.....then it has to be the starter motor?? Was fine for a few weeks up till yesterday! Doing my head in...!

or...load shed relay not shutting off properly: so not enough voltage is reaching the starter?? 

Swapped the horn and load shed, but it didn't make any difference. The headlight shuts off when the ignition is pressed so I thought that was OK.....
Can I test the starter by removing it and connecting it directly to the battery to see if it spins?

Yes, you can bench test it.  Just have a good grip on it when you apply the power.  They have a lot of torque.

I am correct in thinking I can test the starter in situ by connecting the bolted contacts at the starter relay. The starter should spin??

Starter motor is a good’un!! Bench tested, and spun with no issues, nice and powerful. The battery I used was at 12.95v.
So...next suspect is.....

BooG wrote:So...next suspect is.....

If I've understood your descriptions correctly, then according the schematic near the start of the troubleshooting chart on the tech page, it might be the starter relay, a connection to the starter relay or starter, a connection to the ignition control unit, or the control unit itself. Pick one of those to check.

Ok...I can test the starter relay by bypassing it and connecting the two bolted connectors across. This should turn the starter and if it does work...dodgy relay..........correct?

Following on from Laitch's pointer...…..

1. You could remove the start and load shed relays.
2. Using a test lead, connect one end to the battery +ve and with the other end touch terminal 87 of the relay socket.

This should apply a +12 v to the starter motor circuit. Does the motor turn over?

If not you need to look at the starter motor end.

If yes, the fault is further upstream.

Mike

OK...so...we have a result! 
I have to say that the info and pointers given in response to this have been great!
Having bench tested the starter, and even checking that the engine hadn't seized (?), I took to reading the EFi/Electronic ignition troubleshooter article by Crazy Frog, whilst having "parasitic drain" and "damp mornings" in my brain.
Towards the end of the troubleshooter, it directs that if there is power from the battery to the starter relay, then check the lead from the battery to the relay. So I did. Off with the tank, and down into the relay box. Removed starter relay and traced back along the red lead. Then I spotted it....an exposed piece of wire showing signs of corrosion around what looked like  "melted" red insulator. It's where all the red wires meet as they enter the bottom of the relay box. Its funny how all of a sudden, the stars align, and all the reasons for the problem seem obvious: cold and damp mornings getting to exposed wire: parasitic drain thru the shorting out: battery loosing a bit of charge etc etc!! I changed the brushes in the alternator just in case.
Anyway, I finished just before dark, so hopefully I'll get to test her out tomorrow morning!
I should go over the loom and do the cleaning job!!
Thanks chaps...you rock my world!

Good find!  .

Sounds like you may have headed off a potential electrical fire on the bike.

Mike