Starter / starter clutch query

Further to my slow crank query, today I managed to get this troublesome beast to start. It was VERY sluggish turning over.

It stalled when I put it into gear (not unusually, but that’s another story).

On attempting to restart, there was no cranking at all, just a clicking relay and dimming lights. Jumping off the car made no difference.

Now to my question. I suspect the starter has finally died. I’m awaiting delivery of the replacement.

Is there a failure mode of the starter clutch that could lock everything up, preventing the motor from turning?

Logic suggests that if the starter clutch was knackered either the motor would just spin and not turn the engine over, or the starter would continue to be back driven when the engine started. The fact that neither seems to be the case makes me think that there’s nothing wrong with it and it is just a finally dead starter that’s the problem.

Any thoughts?

Think you’ve hit the nail on the head, sounds like the starter motor. As you said when the starter clutch fails you get the starter motor spinning freely and making a rattling sound and I guess if it fails in the engaged state it would start the motor and then spin the starter motor so fast it would self destruct though I’ve not heard of one failing like that. New starter motor should cure it though the starter relays cause problems sometimes, try shorting the contacts of them relay together with a big screwdriver and see if starter motor turns, if it does the relay is knackered.


OK, Guys, I’m bewildered.

My bike has always been tricky to start when cold, taking a few turns and then running roughly for about a minute. The starting got progressively worse until complete starter failure.

Today I overhauled the starter (the replacement I ordered still hasn’t arrived). The brushes had disintegrated, filling the casing with carbon, but that’s another story.

Having refitted the freshly overhauled starter, it starts first push within a second, and instantly runs smoothly at a 1500 rpm idle on choke, and at 950 off choke.

Pick up is smooth and rapid, proportional to throttle position.

My question is this: Why would the simple task of changing the brushes (and cleaning out the carbon, obviously) make such a difference to everything else?

I just don’t get it.

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