Starting Problem - a wierd one

[Cooky]

It's winter so another 'Starting Problem' post I'm afraid.

I commute everyday in town. In the morning and when I get back on bike in the evening I go to start the beast and I can hear the starter motor going but the engine won't fire at all. If I turn off the bike and manually move it forward slightly and then restart everything is fine. Motor fires,ABS kicks in etc, no problems.

Not sure it's a battery problem. It feels more like something gets stuck while the bike is resting that shifts if I manually move the bike.

I know feck all about bike mechanics.

Any pearls of wisdom?

 

[Timolgra]

Check your side stand switch.

If you're in doubt, cut the wires and join them together.

 

[Cooky]

Thanks for prompt reply Tim but why would moving the bike slightly help with the side-stand switch problem?

 

[Timolgra]

Just guessing that you flipped the sidestand when you moved it.

It could also be a problem with the wires/connections at the bottom of the ignition switch and moving the bike affects the contact.

Or..... it's not a 1200 is it

 

[John Armstrong]

Just guessing that you flipped the sidestand when you moved it.

It could also be a problem with the wires/connections at the bottom of the ignition switch and moving the bike affects the contact.

Or..... it's not a 1200 is it

Wouldn't the side stand switch disable the starter, not just cut the ignition?

Could it be the starter is whiring, but moving the bike moves the bendix that then allows the starter to actually turn the engine?

 

[Cooky]

Sorry, I should have said, it's an 1150 (2001)

 

[Cooky]

Dealer has suggested it is "a worn flywheel \ starter sprag" and that it would be prudent to replace clutch at same time. Bike has 30,000 miles on the clock and has never had clutch replaced.

He hasn't seen the bike yet.

Does this sound sensible?

Thanks for any help.

 

[Number 6]

I can hear the starter motor going but the engine won't fire at all.

Do you mean the engine is turning over but not firing or that the starter motor is spinning but not turning the engine over?

 

[Colban]

Dealer has suggested it is "a worn flywheel \ starter sprag" and that it would be prudent to replace clutch at same time. Bike has 30,000 miles on the clock and has never had clutch replaced.

He hasn't seen the bike yet.

Does this sound sensible?

Thanks for any help.

Does the clutch slip?.Unless there is a problem with the clutch,leave it alone.
God knows how much a BMW dealer will charge for a clutch change.
The starter motor sprag clutch is more likely.Its just like a cars and the usual problem is a build up of dust on the shaft/gear that stops the gear engaging with the starter ring.The starter motor is behind the cover with the 12V socket on it (by your LH foot).If you do decide to remove it to look,disconnect the battery first and remove 4 bolts (according to my manual)and pull it out.Clean it,check for damage and ensure the gear runs smoothly along the shaft.Do NOT oil it as that will soon be gunked up with more dust.Dont forget to reset the ECU when you reconnect the battery.Good Luck.

 

[Cooky]

Do you mean the engine is turning over but not firing or that the starter motor is spinning but not turning the engine over?

the starter motor is spinning but not turning the engine over

 

[cookie]

sounds like the solenoid on the starter is not throwing out the pinion. take the starter off & check it works with jump leads.

- to starter body

+ to big live terminal

bridge + above to the small relay connector with a pair of old pliers

oh, and put it in a vice first

if it's making a terrible graunching noise ignore the above

 

[Cooky]

sounds like the solenoid on the starter is not throwing out the pinion. take the starter off & check it works with jump leads.

- to starter body

+ to big live terminal

bridge + above to the small relay connector with a pair of old pliers

oh, and put it in a vice first

if it's making a terrible graunching noise ignore the above

sometimes the starter motor spins relatively quietly. Other times it does the graunchy thing.

 

[cookie]

quiet, smooth whirring likely means the pinion is not moving out.

graunching likely means the pinion is not moving out far enough.

can't be certain from this distance of course, but if it was mine i'd do as above, but before doing the leccy thing, have a look at the state of the teeth on the pinion & on the flywheel. you should be able to see the flywheel through the hole left by the starter.

i imaging there will be some damage to the flywheel teeth. i'd regard some as normal. pinion should be perfect.

i ought to say, i've not actually removed a starter on this model, but done loads similar, so if anyone knows better, feel free to pitch in

 

[Marjorie Proops]

The fact that the bike starts 'fine' after being pushed forward makes it highly unlikely that flywheel / pinion teeth are completely knackered - as said a good clean up of the pinion shaft and the electrocal connections may well do the trick.
Wacky.

'Electrocal' don't you know, sounds sweet, I'll leave it uncorrected

 

[Steptoe]

The dealer could be talking about the starter ring gear, which can work loose on the flywheel, hence the suggestion to change the clutch while your working in there.
If it is the starter ring gear, DO replace the clutch as suggested by the dealer.

I'd take the starter motor off first, and dismantle and clean all the parts, and check the brushes. Doesn't take very long at all, only two bolts hold it in place.
Then see if the problem persists .