Starter (button) issue?

[Robster]

Strange issue with my starter button last couple of times out riding. Happened last week where I'd press the starter button and nothing would happen.

Sounded like a small click from inside the switchgear maybe, as opposed to the click of the starter relay... I think? Happened again today and I must've tried it 20 times, ignition on/off and 10 minutes probably before it eventually started and I could ride home.

I had been out riding (green laning) and had turned it on and off a dozen times during the morning, so strange that it seems to be intermittent - does this sound like the "standard" broken wires at the bottom of the ignition barrel? I didn't think so, because the bike powers up fine when I turn the key...

Any ideas?

 

[Losttheplot]

Strange issue with my starter button last couple of times out riding. Happened last week where I'd press the starter button and nothing would happen.

Sounded like a small click from inside the switchgear maybe, as opposed to the click of the starter relay... I think? Happened again today and I must've tried it 20 times, ignition on/off and 10 minutes probably before it eventually started and I could ride home.

I had been out riding (green laning) and had turned it on and off a dozen times during the morning, so strange that it seems to be intermittent - does this sound like the "standard" broken wires at the bottom of the ignition barrel? I didn't think so, because the bike powers up fine when I turn the key...

Any ideas?

Try changing the starter relay. I had all sorts of electrical gremlins when trying to start the bike, mostly blowing fuses and a few other weird symptons (i forget which ones now), i changed the relay and everything was cured.

Its easy enough to check the wiring on the back of the ignition barrel, there are 2 plastic tabs on the end cap (where the wiring goes in), just push the tabs in and the cap should pop off. Wires should be soldered to 2 pins inside.

Just a thought, when you say the bike wouldn't start, do you mean it just turned over and wouldn't fire? or it just wouldn't do anything?

 

[Robster]

Just a thought, when you say the bike wouldn't start, do you mean it just turned over and wouldn't fire? or it just wouldn't do anything?

Yeah, I mean I hit the starter button and nothing happens – aside from the clicking which like I say sounded like it was coming from the switch itself, although I may well be wrong there!

It's also still doing a weird starting this that it's done for the whole 2.5 years I've had it –*when I start it from hot, sometimes, not always, it will sort do a half turn over as if all of a sudden the battery's flat. If I press the button again, immediately, it'll fire right up. Always done it. New battery when I bought it, and new battery about 3 months ago...still doing it!

Those Italians and their electrics eh?!

 

[Dansin]

Hard starting when hot - decompression lever or exhaust valve clearance?

 

[GFJ]

Broken wires in the ignition switch basically means that nothing happens - you'll hear nothing at the starter at all, only the press of the switch.

A 10 minute job to check - and can be done at the side of the trail. Easy fix with a soldering iron also. Can be put back together with no damage if all okay.

 

[mikecbrxx]

You may also want to ensure your battery terminals are clean and tight. I've had those symptoms and that was the cause.

 

[Robster]

All good suggestions guys, cheers.

I'll try and get some time to strip it down and see what's what and let you know what I find.

 

[Losttheplot]

The starting issue you describe, where the starter only turns the motor over so far, I think is down to the auto decompressor . This is fitted on the end of one of the cam shafts, and relies on centrifugal acceleration to give the engine full compression.
I think if the engine stops far enough into the compression stroke, the decompressor doesn't flick out and open one of the valves, so when the starter is engaged it can only turn the engine until the compression stops it. Give it a few seconds for the pressure to ease in the cylinder and it should crank over properly.

Could also be a tired battery..

 

[Robster]

The starting issue you describe, where the starter only turns the motor over so far, I think is down to the auto decompressor . This is fitted on the end of one of the cam shafts, and relies on centrifugal acceleration to give the engine full compression.
I think if the engine stops far enough into the compression stroke, the decompressor doesn't flick out and open one of the valves, so when the starter is engaged it can only turn the engine until the compression stops it. Give it a few seconds for the pressure to ease in the cylinder and it should crank over properly.

Could also be a tired battery..

That sounds exactly like one of the starting issues for sure - and you're right, over the years I've learnt to just leave it a few second then try again and it always fires right up. It's had a new battery a few months ago so that should be fine. I had the valve clearances checked a while back and was told they were within tolerance which I had suspected might be causing the starter to grind to a halt as I pushed the button. Guess I'll just put up with that then!

 

[Robster]

Oops duplicate post

 

[Robster]

So... mini update.

I have the bike in bits again and sadly, as with my previous blowing fuse F issue, it seems there's no smoking gun! I was hoping for an obviously broken, half-unplugged or rubbed-through wire or something but no such luck!

It occurred to me the other day before I started the strip down, and I should have probably started here first, that I'd been turning the bike on and off with the kill switch (out Green Laning and quickly flicking the bike off with oncoming horses etc) both days the problem happened – so I wondered if the problem was the killswitch part of the switchgear rather than the starter button part as I'd first thought.

Anyway, after pulling it all apart last night and tracing as much of the wiring as I could, I ended up with nothing so I removed the right hand switch gear from the bike for a look and it seemed like the actual killswitch itself may indeed be acting up. A small fortune naturally from Herr BMW, so I've taken a punt on a used one which is winging its way to me now. Probably could've just as well used a universal switch for 1/3 price of the used BMW part, but I figured the plug and play option might make my life easier and be better use of the limited garage time I can wangle at the moment.

Anyone else had any bother with the killswitch? I guess the simple answer is to use the key in future! I'll keep you posted, but I guess the only way I'll know for sure is to go out and test it afterwards and run the risk of stranding myself somewhere!

 

[Losttheplot]

Just a thought, have you bypassed the Sidestand kill switch?

 

[big fella]

I had a similar issue, well my service guy had. It was starting intermittently and the mechanic thought it was the battery voltage. They'd charge up the battery and try starting it a few times a day. They discovered 2 things, 1 that 0.4 of a drop in voltage is enough to not let it fire up, and this is how they found the kill switch was playing up. They were stopping it on the kill switch and assumed it was voltage drop until they checked the battery and found it well charged. They started using the key and no issue. A strip down of the switch found it full of crud. I also have the decompression issue.


Sent from my iPhone using Tapatalk

 

[Robster]

No, I've never had any bother with the sidestand on this bike, unlike on my old DRZ where it would cut out the second I ventured off road!

Good to hear another very similar issue with the killswitch - makes me think (and hope) I'm on the right track.

I reassembled the bike last night and the replacement switch should arrive today all being well. Hopefully that will cure the problem.