Starter Clutch UPDATE

[Preisker]

OK, now when I start the S4, it usually starts.   But, occasionally, and getting more frequent, it spins, but like an old Chevy with a bad solenoid, it doesn't seem to engage the engine.   According to a Duc guy, the sprag clutch is going away.   But he says it's only a couple of hours labor to R&R it, plus parts.   Remove the flywheel and there it is.   Is this correct?  Also, I've heard that it's big bucks for the parts, is this correct also?  

Any experience here is appreciated fellas.  

New issues today.  Had it on the battery tender last night.   Bike cranked slow, popped a few times, and refused to start.   Finally, one big pop, and it fired up.   Rode it to work.   Cranked OK 7 hours later, but wouldn't start on the button.   Starter speeds up and slows down, usually speeds back up and fires up, today, no such luck.  Occasionally, the starter freewheels like a small block Chevy with a bad solenoid (sprag clutch going away?).   Luckily, it bump starts pretty easily. 

Here's my plan, at least the preliminary plan for now, it can change depending on what I hear on here. 

1:  Get the battery checked at the place I bought it, I think it is still under warranty. 

2:   See how many amps the starter is drawing when it is being cranked.    Check all the connections from the battery to the starter and everything else connected to it. 

3:   Well, that's about as far as I have thought it out.    What would you guys start checking?   Do the starters ever go bad?   I know the Ducati tech told me that the sprag clutch has been known to go away, and I'm buying a used low mileage one (thanks Cloner) shortly.    Are the starters rebuildable, if that is the problem?   

I'm all ears guys.   Any and all advise will be appreciated and tried.   

Thanks, Robert

[Dellikose]

http://www.mad-ducati.com/Technical/Engine/AlternatorCover2.html

I saw that link a while back. It seems like a quick fix is to shorten the spring, which can be found here:

https://ccrma.stanford.edu/~peer/Duc/duc-spragSpring.html

It happens to my M900 every once in a while, but it always catches on the second try.

[Preisker]

Awesome Delikose, I really appreciate the info, and it looks like exactly what I was looking for.   

But, the bottom end pictures and flywheel removal are for an air cooled engine, is the water cooled engine the same?

Thanks again.

[Dellikose]

As for the air vs. water cooled, I'm sorry but I couldn't tell you.

Don't worry though, someone will chime in soon

[ducpainter]

Awesome Delikose, I really appreciate the info, and it looks like exactly what I was looking for.   

But, the bottom end pictures and flywheel removal are for an air cooled engine, is the water cooled engine the same?

Thanks again.

On the water cooler you naturally have to drain the cooling system to remove the cover...

otherwise they're pretty similar inside.

[Preisker]

Thanks Painter.

[Cloner]

I never had good luck with the spring shortening solution, but a good alternative is to simply replace the spring.  I'll have to do a little looking for the receipt, but you can buy a seal at your local bearing house and use the spring from the seal to replace the clutch sprag spring.

I also have the entire flywheel assembly (including the clutch sprag and all the bearings) from an ST2 that's about to go on ebay for a buck (starting) if you'd just like a new assembly from a bike that was totalled with about 3k on the clocks.  Two and four valvers before the 999 (I think) share a common starter, starter clutch, and several other bottom end bits.  Later starters (two and four valve) have an extra bolt on the outside end of the starter.