Starter Motor
  • The DR650se starter motor in it's stock form is also subject to the onset of a rather noisy squark or rooster call caused by a dry bushing in the outer end cap which can be fixed by removing the outer end cap and lubing the bushing or replacing the end cap with a Warp 9 version that has a sealed bearing rather than a bush to take the end of the armature shaft. I installed a Warp 9 end cap on mine prior to this latest failure.

  • HISTORY    -    The DR650se Starter Motor is prone to wear and tear like any other starter motor but it is also prone to damage from moisture getting inside. The main cause for this can be from the two large O-rings in between each end of the body and the inner and outer end caps allowing water in. Typically, the O-rings can become deflected or pop out of place when reassembling particularly when they are reused rather than replaced. In addition, old or stretched O-rings are never going to seal properly and some random bikes have been known to come out new with an ill-fitting O-ring from the factory. The Starter also sits in a cavity or well on top of the gearbox/crankcase which has a drain hole to allow water to drain from the cavity when the bike is on the sidestand. If that drain hole gets blocked, water can well up in there and literally leave the starter motor sitting in a pool of water. I also believe there is a possibility of water entering the starter from the rapid cooling effect when traversing deep water crossings, allowing water to pass by the O-rings. In any event, a build up of rust and corrosion inside the starter motor is likely to cause the brushes to seize in their holders and no longer contact the armature leading to the failure of the starter motor to operate. This happened to mine at around 60,000kms and 11 years of age. The bike had sat for about 3 weeks without being started after being washed and following a 3 day ride that included several creek crossings ranging from shallow to up to approx 600mm deep.
  • SYMPTOM    -    No Turnover of the Starter Motor when hitting the Start Button
  1.  Following an earlier failure to start and then finding my motobatt AGM battery had gone dead flat and wouldn't take a recharge, I purchased a brand new SSB lithium Battery, so I knew that the battery was no longer the problem. I tested with a multimeter anyway for both voltage and voltage drop when hitting the starter button. There was no noticeable difference and battery voltage was showing 13.40 volts - about right.  All lights etc were working and I wasn't getting a constant clicking from the starter solenoid that one would with a low battery.
  2. I could hear the starter solenoid clicking just once each time I hit the Starter Button which is normal, so the solenoid should be ok.  I checked for voltage on the output side when I hit the starter button which all checked out ok, so I was getting voltage out to the starter motor.
  3. I then tried a jump start of the Starter Motor itself by eliminating the solenoid and using two jumper cables - one from the battery negative post to the body of the starter and the other from the positive (live) post to the starter motor terminal and I got nothing but silence. If the starter was ok, I would have gotten sparks from the terminal when I touched the live lead on, and the starter would have spun -Too easy, Starter motor it is.

Proceed to remove and service the starter motor

  • Note: The following procedure involves removing the Cam chain tensioner (CCT) to more easily access the starter motor for removal. It may be possible to remove the starter motor without removing the CCT but it is a more difficult operation and involves partially disassembling the starter motor in-situ and visa versa to re-instal. My recommendation to avoid any mistakes particularly with reassembly is to remove the CCT. A new CCT gasket may be required.

  • Set engine to Top Dead Centre on compression stroke.    - see my page  Finding  (TDC) on Compression Stroke 
  • Remove header pipe (it may be necessary to remove whole exhaust system depending on what system you have) - block exhaust port with a rag.
  • Remove oil line from head and case banjos and flex out of the way - take care not to lose the copper washers and place banjo bolts back in lightly to block port off whilst working on the bike.
  • Remove Cam Chain Tensioner (Ensure TDC compression stroke before doing so) and place to one side - temporarily block port off with a rag to prevent anything entering the engine whilst working on the bike.
  • (optional) Remove clutch arm by first marking the arm and the spline in order to get correct alignment on reassembly. Slide clutch cable with arm in place out of it's holder on the starter motor bracket and swing cable out of the way.
  • Disconnect battery
  • Disconnect Starter lead wire
  • Remove the Clutch cable/Starter Motor holding bracket and place to one side.
                                                     The Starter Motor can now be removed from the bike

  • The Starter Motor should now be able to pulled free from the right hand side of the bike 
  • If it needs a little persuasion, give it a gentle tap from the left hand side of the bike using a piece of wood and hammer until it breaks free.

Disassembly of the Starter Motor for inspection and service/cleaning

Remove the two starter motor housing bolts 
Pull the outer end cap off and large body o-ring
Moisture condensation evident inner end cap on removal. Obvious cause of this is the failure of body o-rings to seal.
Poor condition of brush holder and contacts from water ingress led to failure of this starter motor due to seized carbon brushes
Pull the inner end cap off the armature shaft followed by the washer set
Tab washer, 1.0mm fibre washer, .20mm  washer and .50mm washer 
Pull Armature Shaft from the body, spline end first.
There will be some resistance due to the magnets but it will come.
Remove and take care not to lose the washers on the commutator end of the armature shaft and note their order on disassembly
Discolouration and contaminants on the commutator leading to poor conductivity 

Next is to remove the brush holder from the body

First remove the terminal nut(s), the steel washer, 1 larger insulating washer then 2 smaller insulating washers.

Push the terminal post down in to the starter body while you are pulling the brush holder away from the end of the body. As you are pulling the brush holder away from the body, the terminal holding bracket will come away from its slots inside the end of the body behind the brush holder. The terminal holding bracket is also the live feed to the positive brushes.
  • Front side of Brush Holder
  •  Rear side of Brush Holder with Terminal still attached
The carbon brushes should be able to move freely within their individual holders and spring pressure hold/forces the brushes down against the commutator to make contact. 
The problem with my Starter was that moisture had entered the starter and rust and corrosion had cause the brushes to seize in their holders to the extent that after several starts, the brushes stopped making contact with the commutator and thus no turning over of the starter motor.
It is at this stage you would assess whether to replace/renew the brush assembly or recondition existing one

Removing the carbon brushes from their holders for reconditioning

With the armature/commutator already removed and out of the way, the carbon brushes should be able to be pushed through and out of their holders by the springs themselves but in my case because the carbon brushes were seized, I had to give them some gentle persuasion. A gentle light tap with a punch on top of each spring was enough to get them moving and to keep tapping until each brush had worked its way out through the bottom of their holders.
To aid cleaning and to make reassembly possible, each spring was then removed by prying the leverage end of the spring out of the brush holder with a small screwdriver and holding it there while then using another screwdriver to lever the spring from its post.

Fully disassembled ready for cleaning and servicing
Cleaning and Servicing
Cut a strip off a thin piece of timber to make a rectangular cross section stick and a small square section of sandpaper

Sandpaper wrapped around stick is used to sand down the internal section of each brush holder and into the corners to remove the rust and smoothen the surface
remaining external surfaces were treated with a small fine wire brush and sandpaper and then cleaned and dedusted with contact cleaner
Give the carbon brushes themselves a light sanding to smooth the sides

Discolouration inside body - give a light sanding with fine sandpaper and then clean with contact cleaner
Give the commutator a polish with fine sandpaper to remove discolouration. Gently clean out groves to remove any build-up.
Check that there is continuity between each segment of the commutator and the also check there is no continuity between each segment and the armature shaft

Inspect the inner end cap bearing and seal behind it. Replace seal if it shows signs of wear or damage. Inspect and replace outer o-ring if showing signs of wear or damage. * Note: The bearing in this cap is lubricated by engine oil from inside starter clutch.                                                                               
Inspect Body o-rings for damage, distortion and Stretching. It is from my experience that I recommend replacing these whenever the Starter Motor is disassembled. 
A good comparison of the old versus new. The old o-rings are distorted and stretched and will never seal like they should.         


O-ring Part Numbers
End Cap/ Body O-rings x 2
Inner End Cap Outer O-ring

Reassembly (reverse of disassembly)

Place each Carbon Brush Back in their respective holders without the springs fitted. Feed terminal back up though hole in body and locate the Terminal bracket into its slots in the end of the main body and then push brush holder into place on the end of the main body. Feed armature shaft through body, commutator end first. You may need to push the carbon brushes up out of the way to make way for the commutator.
Place springs back on posts and use a screwdriver to wind brush contact end of spring back up to locate it in the slot on the brush holder whilst holding the spring in place on the post so it doesn't spring off. A little bit tricky but you'll get it if you hold your tongue right. The brushes should push down and stay down against the commutator under the spring pressure.
Place washers in correct orders as when disassembled, replace the inner end cap/body o-ring and install the inner end cap. *It is my recommendation that you don't grease these end cap/body o-rings. Grease will potentially cause the o-ring to pop out of its groove.
Place washers as disassembled back on end of armature shaft, replace outer end cap/body o-ring, and install outer end cap. Note: if you still use the stock end cap, grease the end of the armature shaft or buy a nice Warp9 end cap which has a bearing.
Install starter motor housing bolts and torque to approx 3.5nm - 
check o-rings for seal.

Bench test Starter Motor - make sure you hang on to it or it will spin away out of control. You will also get quite a spark when the positive lead contacts the terminal but that's normal and nothing to be afraid of.