Bike won't start. Help!!

[Bendy toy]

If the bike battery is a full wet cell (not AGM) the active material and sulphate gradually drops out into the space below the plates. Debris build up eventually shorts out one or more cells.
Shorted cells go instantly flat and lose even more active ingredient.
Along comes the jump leads. If more than one or two cells are down there won't be enough voltage to drive the starter.
If you have well insulated ends on the jump leads clip the positive lead to the bike starter terminal. If the starter turns when the circuit is made (from the car battery end) - the bike starter motor is ok.
Disconnect the bike battery earth. Clip jump earth to the lead and don't allow it to touch the bike battery earth terminal. Clip positive as normal. If bike starts the battery is flat/scrap.
Of it does not it's probably brushes in the starter motor.
Don't run the car engine as this can overload bike's alternator regulator and bike starter motor back emf can upset delicate stuff on the car.

 

[Banjo]

I think I've been describing the symptoms wrong.... It's not a quiet click like the click of a relay, but more like a big loud clack clack
Like a chatter. Possibly the coil closing the switch at the starter motor but nothing else. Sorry I've probably been misleading.

 

[Banjo]

I think I've been describing the symptoms wrong.... It's not a quiet click like the click of a relay, but more like a big loud clack clack
Like a chatter. Possibly the coil closing the switch at the starter motor but nothing else. Sorry I've probably been misleading.

 

[Kiwi_Mike]

I'm facing the same issue although I am getting a 'click' from the relay under the tool pouch. I removed the plastic tray and the tool pouch and found to my suprise about an inch and a half of blue water sitting in the bucket that BMW in the wisdom have put under there. Why on earth there is no drainage hole is beyond me. The red wire going into the bottom of the relay has corroded off so i need to try and pull the whole thing apart so I can solder it back on. Once I borrow a soldering iron off Alex_RSA. I will also be drilling a drainage hole at the bottom of the bucket.

Thats what you get when you spend a bank holiday Monday riding from Whitby to London in driving rain using the windy road setting on the Tom Tom.

 

[Kiwi_Mike]

I managed to fix my issue. I couldn't get the connector out of the black plastic block that the relay slots into so I had to cut/force it out and replace it with a new connector through the space left behind.

I did actually find a (way too small in my opinion) drainage hole in the bottom of the 'bucket' but it was clogged with road grime. I guess the moral of the story is you have to make sure you keep your hole clean

 

[Pukmeister]

Sounds like the pinion is trying to engage but the motor cannot turn over e.g. Either dirty or sticking contacts, brushes etc or the motor windings are faulty.

 

[Roymondo]

If you're still getting click-click-click (and the instruments dying when you press the starter) even with a car battery providing the oomph then the culprit is very likely to be a loose or corroded connection in the main battery cables. Check them all - especially connections to starter/solenoid.

 

[Banjo]

Well I've taken the starter motor off and connected it to the spare battery and put 12v onto it via battery possible and small space on solenoid, the cog shoots forward but doesn't rotate, so I guess duff motor. I also noticed some rust on the flywheel that it engages into.

 

[mikpow]

Had exactly the same thing 2 days ago, click (loud) with bike battery, Click several times (v loud) with jump leads. Optimate said all OK with battery. Put new battery on bike and all is well with the world.... Don't know why it wouldn't even turn on jump leads but it didn't.

 

[Roymondo]

Optimates are OK at detecting some battery problems - but what they cannot do is stick a big, heavy load on the battery and see how it responds.

 

[Bendy toy]

Had exactly the same thing 2 days ago, click (loud) with bike battery, Click several times (v loud) with jump leads. Optimate said all OK with battery. Put new battery on bike and all is well with the world.... Don't know why it wouldn't even turn on jump leads but it didn't.

Next time disconnect the bike battery earth and try again with jump leads. If the engine starts suspect the bike battery has an internal short.
The Optimate should find this sort of fault. Sometimes however the battery can be ok flat on a table but tilted a little will move enough sludge lying at cell bottoms to short the plates.

 

[Pukmeister]

Well I've taken the starter motor off and connected it to the spare battery and put 12v onto it via battery possible and small space on solenoid, the cog shoots forward but doesn't rotate, so I guess duff motor. I also noticed some rust on the flywheel that it engages into.

Can you make the pinion physically rotate, or is the motor shaft jammed? Had a car starter jam once due to pilot bush wearing through the casing, jamming the motor shaft. Fixed by rebushing in the lathe. Also had the physical contacts inside the solenoid that put power to the windings once engaged cause trouble, which is my best guess as to the cause. Can you strip and inspect the starter and solenoid?

It could just be that your carbon brushes are worn or the commutator needs a clean up and the segments undercutting. Earlier GS models had jamming issues when the magnets became unglued but not seen that on a 1200.

Maybe get a tested spare starter from motor works then rebuild your faulty one in slow time and keep as a spare/resell?

 

[Banjo]

Well, I've just pushed it up the hill where I live and bump started it. It started ok. Is it ok to have a go at starting it with one of those booster jump start kits you get for cars???

 

[Bendy toy]

I've just posted a "how to" on basic starter overhaul.

 

[Banjo]

Its alive. Its alive!! Renewed the battery and cleaned the terminals on the starter motor. Thanks for the input fellas.

 

[Pukmeister]

Its alive. Its alive!! Renewed the battery and cleaned the terminals on the starter motor. Thanks for the input fellas.

Result ! Cheaper than buying a new starter.

 

[Bendy toy]

The. brush holder in my starter was rusting. Another year and I'd have needed a new motor. It wasn't difficult to clean and protect with ACF 50. Remove only the two small hexhead screws and the whole armature comes out.