starter motor advice please

Just taken delivery of a monster 900 s ie
she's great but wont start on the button.its as if
some thing isnt engaging it makes to start but
stops before turning over ? I can get it started by
putting it into second and then rolling it downhill
before pressing the starter whereupon the starter
engages and the motor fires and then its tease her
into life.not the coolest or most healthiest of start
procedures but it got me home and now of course
the question is Why.
Any Guru's care to advise me on this strange
phenomenon and hoe I can cure it .
please please my calm is shattered

[Stafford]

Could be battery condition, starter solenoid or starter motor brushes.
Welcome BTW just down the A4 in Calne.

Welcome aboard
Get yourself a cheap multi meter and check what voltage the battery is reading
Alan H

[Flip]

Good advice already- a multi meter is a must to check things over properly and obviously check the easy things first as already mentioned too.

The big main (Yellow) relay under the seat can be problematic so prize the cover off and look at the contacts- if possible get it running with it open as some bikes when turned off by the key allow the coils to discharge through it causing a spark and thus eroding the contacts (cause of the problem). This can be minimised by shutting it off by the Run/Stop switch before the key or fitting a little capacitor to take the hit from the coils.

Another cause could be the earth strap from the starter- some bikes have crimped connections which over time can build up a bit of resistance meaning the starter is slow to turn- easy fix is buy an earth strap from a later bike at they are soldered connections (or make your own of course). But at the very least have a look there and clean it all up as because od starter location they get all the road crap over them.

Ideally try not to repeatedly try and start it on the starter with a run down battery etc. as it is easy to damage the Sprag Clutch.

[Capo]

Sprag clutch

[Stafford]

Originally Posted by Capo

Sprag clutch

I was going to say sprag but thought that if the bike fails to turn over the sprag would have engaged and the fault would lie elsewhere.

[Capo]

If the sprag is faulty, the starter will turn over but the engine won't

[SteveM900]

My recently bought 94 M900 struggled to turn over despite the new battery. The problem was at the starter motor connection which due to its location was badly corroded. It snapped off it was that bad, was hoping to clean it up.
Bought a new brush plate about £30 , it can be fitted with the starter in place, just need to remove oil cooler pipe and union first.
Also fitted a heavier duty cable from the solenoid to the starter. Spins over a treat now and starts really quickly.
Worth checking.

[Stafford]

Originally Posted by Capo

If the sprag is faulty, the starter will turn over but the engine won't

I had the impression that the starter motor stops "it makes to start but stops before turning over"

thanks Gents ,I now Know what to look for .also could the side stand switch affect the start up?
I have also yet to under stand the setting up of a power commander 3 in conjunction with some
Venom type end cans that were rebaffled for MOT by the shop. I m an engineer but not an adept
could be I will be fettling for a while.all the same Thank you all

[Capo]

Originally Posted by Stafford

I had the impression that the starter motor stops "it makes to start but stops before turning over"

I am assuming it has the "press the start button once" to initiate the start sequence, the starter then runs until either the engine starts or times out on a no start.

i was unaware of a start sequence that is a control system feature
all I know is some choke ,sidestand up and press starter button
as a newbie to the monster fraternity I naturally have a fair bit
to learn even though I ve been riding for 35 years. please tell
me more

[Capo]

Do you have to hold the starter button down for the starter to operate, does the starter stop or continue to run when the button is released?

Later bikes had this feature controlled by the ECU, and as yours is injected and therefore has an ECU, I assume it has this feature. Check the owners manual.

BTW its not a choke, rather a fast idle.

Hi to all you wise ones ,I checked all the items mentioned and then found that the battery had no electrolite in it .topped up charged and wahey bike starts on the button with the fast idle at its extent.
Question though I think the oil pressure sensor has failed so if the sump window shows oil I can still run the bike no? why do they fail though? also the side stand bolt was loose this may have been a factor.
I will now post an image of my new favorite

[Darren69]

I would still get a meter and check your bikes not overcharging, if the battery was dry, just to be on the safe side. Also check the battery overflow pipe is connected to the breather and is routed to minimise any possible acid damage to frame or engine cases.