Starter motor change - '93 M900

Goofle · 17-05-2020, 01:07 PM

Not sure if this should go in 'engine, clutch and gears' as its a mechanical question, or 'electrics' as its a motor. If I'm in the wrong spot, sorry!
I've just got the Keihin carbs in, fitted, engine running and, so far, no fuel leaks. I'm happy! Then the bike stops dead, no electrics at all. Main 30a fuse blown, fuse replaced, electrics now working - apart from the starter. Investigation shows the motor failed, and is totally open circuit. How big a job is removal and replacement please? Is it likely to be something in the motor that I can sort easily (worn brushes for example) or should I just get a new motor ordered?

Thanks all!

Ps it sounded well with the carbs, and seemed eager to rev! I've not ridden it yet however...

Darren69 · 17-05-2020, 01:26 PM

It's not a big job but laborious since it involves removing the left hand cover as there is one additional internal bolt holding the starter motor as well as the 2 external ones. They put holes in the starter gear wheel so you can get it undone easily once the cover is off.

Darren69 · 17-05-2020, 01:31 PM

You'll need an alternator puller and to be aware of the bolts that are near the clutch slave/rear sprocket and make sure you remove them first before pulling the cover off.

slob · 17-05-2020, 01:33 PM

alternator COVER puller, the alternator shouldn’t need touching

Darren69 · 17-05-2020, 01:37 PM

yea sorry, thanks Rob, cover puller.

Darren69 · 17-05-2020, 01:42 PM

Also be aware if replacing the starter with a different one, that most are the same motor unit but the later ones had a different gear fitted. (Post '00 or 01' I think iirc, maybe earlier?). I don't know if it's possible to swap the gears over however.

350TSS · 17-05-2020, 01:43 PM

You will need the cover extractor tool about £10 off e bay that screws into the two 6 mm screws on the outside of the inspection plate on the alternator cover.
DO NOT FORGET the screw holding the alternator cover near the clutch push rod area if you do and use the extractor tool you will crack the alternator casing. Do not ask me how I know.
Ducati does not supply gaskets for the alternator cover any more preferring to rely on their expensive gasket goo. Use this sparingly as any surplus squeezed out on the inside of the alternator casing ends up in the sump and/or possibly oilways.
When tightening the power cable to the new starter motor make sure the post itself does not turn if it does you stand a good chance of destroying the internal wires to the brushes.
With the extractor tool and no recalcitrant fasteners about an hours job start to finish

Darren69 · 17-05-2020, 01:50 PM

You can I think still get gaskets from Exact fit/CCW if you want one.

Goofle · 17-05-2020, 01:53 PM

Thanks to all who’s replied so far!
I‘ve been looking at the Haynes manual and it seems to imply I need to remove gears from under the alternator cover to access bolts? I’ve had the cover off before when the gasket started leaking last year and have a homemade puller, it’s not ideal but does work. I take it it’s a oil drain first too?
Thanks again!

Darren69 · 17-05-2020, 01:57 PM

You shouldn't need to remove any gears afaik there are holes in the gear wheel that will allow you to get an allen key in to undo the starter motor bolt.

Goofle · 17-05-2020, 02:18 PM

Quote:

Originally Posted by Darren69

You shouldn't need to remove any gears afaik there are holes in the gear wheel that will allow you to get an allen key in to undo the starter motor bolt.

Great, thanks!

slob · 17-05-2020, 02:45 PM

the gears swap out, no problem, if you need to. just held on with a circlip.
the later ones my have an extra lug for a fourth bolt at the other end but should be interchangeable anyway.

Darren69 · 17-05-2020, 02:57 PM

So now you know. it's Just another step. I did think it would be possible but I hadn't heard of it being done before. Thanks Rob

alan s4 · 18-05-2020, 08:49 AM

I've done the job recently. Ended up buying a new starter motor (circa £110) as the brush repair kit was around £40.00, being lazy/mechanically inept I went for the easy option.

If you are buying a new starter make sure you keep the cog from the old one and swap it over. I didn't and had to do the job again.

slob · 18-05-2020, 09:11 AM

and don't forget the 'sharp' side of the circlip sits outwards

17-05-2020, 01:07 PM	#1
Goofle Registered User Join Date: Feb 2014 Location: Powys Bike: M900 Posts: 334	Starter motor change - '93 M900 Not sure if this should go in 'engine, clutch and gears' as its a mechanical question, or 'electrics' as its a motor. If I'm in the wrong spot, sorry! I've just got the Keihin carbs in, fitted, engine running and, so far, no fuel leaks. I'm happy! Then the bike stops dead, no electrics at all. Main 30a fuse blown, fuse replaced, electrics now working - apart from the starter. Investigation shows the motor failed, and is totally open circuit. How big a job is removal and replacement please? Is it likely to be something in the motor that I can sort easily (worn brushes for example) or should I just get a new motor ordered? Thanks all! Ps it sounded well with the carbs, and seemed eager to rev! I've not ridden it yet however...

17-05-2020, 01:26 PM	#2
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	It's not a big job but laborious since it involves removing the left hand cover as there is one additional internal bolt holding the starter motor as well as the 2 external ones. They put holes in the starter gear wheel so you can get it undone easily once the cover is off. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

17-05-2020, 01:31 PM	#3
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	You'll need an alternator puller and to be aware of the bolts that are near the clutch slave/rear sprocket and make sure you remove them first before pulling the cover off. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

17-05-2020, 01:37 PM	#5
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	yea sorry, thanks Rob, cover puller. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

17-05-2020, 01:42 PM	#6
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	Also be aware if replacing the starter with a different one, that most are the same motor unit but the later ones had a different gear fitted. (Post '00 or 01' I think iirc, maybe earlier?). I don't know if it's possible to swap the gears over however. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

17-05-2020, 01:33 PM	#4
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,710	alternator COVER puller, the alternator shouldn’t need touching

17-05-2020, 01:43 PM	#7
350TSS Too much time on my hands member Join Date: Jan 2013 Location: Shipbourne Bike: M900 Posts: 1,419	You will need the cover extractor tool about £10 off e bay that screws into the two 6 mm screws on the outside of the inspection plate on the alternator cover. DO NOT FORGET the screw holding the alternator cover near the clutch push rod area if you do and use the extractor tool you will crack the alternator casing. Do not ask me how I know. Ducati does not supply gaskets for the alternator cover any more preferring to rely on their expensive gasket goo. Use this sparingly as any surplus squeezed out on the inside of the alternator casing ends up in the sump and/or possibly oilways. When tightening the power cable to the new starter motor make sure the post itself does not turn if it does you stand a good chance of destroying the internal wires to the brushes. With the extractor tool and no recalcitrant fasteners about an hours job start to finish

17-05-2020, 01:50 PM	#8
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	You can I think still get gaskets from Exact fit/CCW if you want one. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

17-05-2020, 01:53 PM	#9
Goofle Registered User Join Date: Feb 2014 Location: Powys Bike: M900 Posts: 334	Thanks to all who’s replied so far! I‘ve been looking at the Haynes manual and it seems to imply I need to remove gears from under the alternator cover to access bolts? I’ve had the cover off before when the gasket started leaking last year and have a homemade puller, it’s not ideal but does work. I take it it’s a oil drain first too? Thanks again!

17-05-2020, 01:57 PM	#10
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	You shouldn't need to remove any gears afaik there are holes in the gear wheel that will allow you to get an allen key in to undo the starter motor bolt. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

17-05-2020, 02:45 PM	#12
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,710	the gears swap out, no problem, if you need to. just held on with a circlip. the later ones my have an extra lug for a fourth bolt at the other end but should be interchangeable anyway. Last edited by slob; 17-05-2020 at 02:52 PM.. Reason: added pics

17-05-2020, 02:57 PM	#13
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,022	So now you know. it's Just another step. I did think it would be possible but I hadn't heard of it being done before. Thanks Rob __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

18-05-2020, 08:49 AM	#14
alan s4 Registered User Join Date: Sep 2013 Location: Glasgow Bike: S4 challenge Posts: 447	I've done the job recently. Ended up buying a new starter motor (circa £110) as the brush repair kit was around £40.00, being lazy/mechanically inept I went for the easy option. If you are buying a new starter make sure you keep the cog from the old one and swap it over. I didn't and had to do the job again.

18-05-2020, 09:11 AM	#15
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,710	and don't forget the 'sharp' side of the circlip sits outwards