Is my starter going?

[rufusswan]

How about a picture? Since them things remain so hidden on the bike it's a bit of a stretch on an old mans memory. Show what you got 'on the bench'.

[mark1305]

Hi Chad. Without seeing it up close I tend to think like a couple of others that the brushes may be beyond their lifespan and just being disturbed may have put them out of their misery. If you clean(ed) the commutator that the brushes ride on, make sure any copper dust gets cleaned out from between each little contact segment.

Don't know if you have any good old school electric shops up there. We used to have great one here on the Island, but they closed doors about 2 years ago. But a good old time shop should be able to refurb any kind of starter.

[photorider]

If you decide to rebuild it, here is a good write-up with pics. It was very helpful when I did mine a few months back:

http://www.thisoldtractor.com/gtbend...ir_-bosch-.htm

[Sergeant Joe]

G'day, I had the very same thing on my R65LS.
The fix is to run an Earth wire from Neg side of Dioad board through to the bolt that holds the back of the starter motor to the engine case.
This gives a full Earthing system as the way BMW did it sucks.
I have had full charge an instant starter turnover ever since.
hope this helps.

[Wirespokes]

Originally Posted by Sergeant Joe

The fix is to run an Earth wire from Neg side of Dioad board through to the bolt that holds the back of the starter motor to the engine case.

Makes no sense to me that since the starter grounds through the engine block at it's mounting point. Can't get much better grounding than that!

The best test for the starter (with a known good battery) is to hook jumper leads directly to the starter while it's installed.

Run the negative jumper from the battery negative to the engine block near the starter.

Connect the positive lead to the cable mounting lug on the starter.

Jump 12V to the solenoid spade and the starter should spin the engine.

If it doesn't, something aint right with the starter.

It's possible to have a poor connection in the solenoid contacts.

Often it's worn bushings in the starter - there are three - two for the armature, one in the bendix drive.

Or it's brushes and grungy commutator.

If the starter turns when the button is pressed, it's not the relay - since that's what the relay's function is - to activate the starter.

[mfp4073]

thanks for all the replies

The trick that was missing was what crazydrummerdude mentioned. You have to put 12v to the spade connector in addition to the main positive.

So here were my tests today, tested it on the bench with a battery providing power. Seemed like it wound up ok, but my suspicion is the bearings are going. Seemed like it wound down to fast and was "vibrating" a bit more than I would have expected during wind down. I got none of the solenoid clicking.

Next test, lay it on the engine, hook up batter and starter and test it with the bikes starting system. Same result. At this point started to think that there was a contact issue that I disturbed and it "fixed itself"

Put bike back together with the idea that the starter needs replacing due to the bearing/wind down feel, but that I had fixed the problem. Yeah, no. Went back to the old turnover, clicking, turnover, clicking thing.

GRRRRRRR.

[Wirespokes]

I think it needs the bushings replaced.

[mfp4073]

Originally Posted by Wirespokes

I think it needs the bushings replaced.

Even if everything else were normal, I would agree to this statement.

[Sergeant Joe]

Bad earth is the culprit 95% of the time. Just saying

[mfp4073]

here is a strange update......

As listed I got the bike/starter apart and everything tested normal as best as I could test. Still go the clicking and not "catching" and cranking like it should.

I was going to next look at battery cables, but didnt get the time as my alternator rotor failed and had to be replaced.

Here is the strange part. In the last 2 days since I have had the bike back on the road with a new rotor/brushes in it I dont get the clicking solenoid anymore. I dont get it myself? How can the two be related?

[Wirespokes]

Does this mean the starter is working normally with no clicking solenoid, or...

When you press the starter button you don't get anything, not even get clicking?

[mfp4073]

Originally Posted by Wirespokes

Does this mean the starter is working normally with no clicking solenoid, or...

When you press the starter button you don't get anything, not even get clicking?

Sorry about that. Yeah, its working normally. Odd huh?

[Wirespokes]

Sounds like the battery was low, and the root of the problem was the failing rotor.

[mfp4073]

Originally Posted by Wirespokes

Sounds like the battery was low, and the root of the problem was the failing rotor.

When this was happening, I was charging and testing the battery regularly to make sure it was not low because that was my first thought. Cant imagine the battery being low for several months at a time?

[chasbmw]

if the starter only gives problems when it is under load, then ther problem is often due to wear in the bushings, this allows the armature to cock sideways under load and everything starts to go really slow.

I dont know if the bushs are available for these old 8 tooth Boschs, but given that you can buy either Valeo or Nippon Denso 8 tooth starter motors nowadays I would go for replacement.