Classic starter problem

[TRIDENT]

Starter spins but not turning over engine ?why.Is it a pre engaged type or inertia.If got to remove starter what is procedure looks a bit awkward.

[tim harrison]

Is it the starter sprag clutch. If it is not gripping the sprocket the starter will spin but won't turn the engine. This is a common problem on the Mk3 Commando but the freer spinning rotary with no backfire does not wear them out so quickly.
Tim

[TRIDENT]

Hi Tim Harrison im David Harrison,after more research it is a sprag type have changed primary oil and will see if thet helps ,doesn't always happen so will have to see,have not yet found what sprag bearing fits if it needs replacing any info would be great.

[tim harrison]

The sprag has to be matched with the drive gear and engine sprocket. It is generally recommended that the three are installed together as new parts. Obviously much easier said than done with your bike. If the sprocket looks good Andover Norton has the 18 tooth sprag but yours maybe the 14 tooth version which they do not have.

New oil and a bit of use may sort it out.

Graham at Startright is probably your best bet for info and parts.

[TRIDENT]

cheers awaiting bit better weather now changed oil,as you say hope more regular use will help.

[johnbirchjar]

I doubt that changing the oil will help,I had to put new sprag clutches twice in my Classic (they seem to be a bit of an "Achilles Heel" with air cooled rotories)I can't remember the exact mileage,but it wasn't that many and I no longer have the bike so I can't refer to the records,but the old girl had only done about 70,000 miles when I sold her,and be warned it is not a five minute job ,and if memory serves, you will need the clutch tool,good luck,J.B.

[Anthony Duffield]

David,

My Commander starter motor just ran without turning the engine, I found putting it in gear and rocking back and forth got the sprag working again for a while, when I eventually got the sprag out (page 10 of the Commander parts book) I found the sprag to just be dirty, all it needed was a good clean.

Tony

[Richard Negus]

I agree with Tony's suggestion to dismantle and clean the sprag of any oil sludge.
And while you're in there, scrub any sludge off the clutch plates and out of the splines in the clutch drum. You'll get a much nicer clutch with less of a 'clunk' when engaging 1st gear.
Finally, when replacing the sprag in the clutch drum, make sure it's the right way round.
R.