Sprag clutch failures

duck-a-tye · Post by **duck-a-tye** » Sun May 30, 2004 1:31 am

Hi

can anyone help with common reasons (things to look for) for the starter sprag clutch failing (free wheeling) in a MHR Mille cause i'm on my third!

Thanks
duck-a-tye

Desmor · Post by **Desmor** » Sat Jun 02, 2007 11:07 pm

What oil are you using? maybe fully synthetic would help?

Vince · Post by **Vince** » Sat Jun 02, 2007 11:40 pm

There is an uprated one avalable from the central coast,Gosford,
Made by Howdi Ingeneering,there is one for a Laverda on ebay at the moment,very strongly made.

Vince · Post by **Vince** » Sun Jun 03, 2007 12:57 am

Bit on the slow side,probably got grandkids now.

duck-a-tye · Post by **duck-a-tye** » Fri Oct 19, 2007 11:06 pm

Hi Guys

yes I posted this question back in 2004, but that's fine, I'm happy to get any advice/suggestions even if they take a while......... :-)

Cheers
Barry

duck-a-tye · Post by **duck-a-tye** » Sat Oct 20, 2007 4:38 pm

I hate to admit it, but it hasn't run since 2005! I stripped it down to repaint the frame and tidy up the motor, and just then the missus decided she wanted two more rooms on the house!!!!!

This years just about finished, but hopefully 2008 will see some work being done on it.

Lucky I've got the 750 sport for the times when I'm let of the leash

Barry

Post by **BevHevSteve** » Mon Oct 22, 2007 12:31 am

the SVR20 battery I sell has 300 CCAs - and it is a sealed AGM battery which means NO SPILLS and NO MAINTENANCE.

You typically screw up the starter sprag when your engine is not in tune - it backfires while you are turning the starter and your sprag bearing is toast.

The answer is to rebuild your carbiew at least every 2 years with new seal kits etc, and, pay close attention to carb sync

duck-a-tye · Post by **duck-a-tye** » Mon Oct 22, 2007 2:22 am

Thanks Peter and Steve

When the time comes I will get one of these batteries, I remember that the starter would literally groan when the piston came onto compression, and then she would thunder into life (usually) a truly glorious sound. (thanks to the 2-1 exhaust) I can't remember any back fires tho'.

This is still the best duke site, keep up the good work guys!!

Barry

scott · Post by **scott** » Thu Dec 24, 2009 12:19 am

gday,
I know its acouple of years since last message so I presume you still have the same problem. Me too. Ive lost count how many starter clutches Ive been through.
The clutch is simply not up to the job of turning over the motor with a starter motor half the size of my old darmah to drive it. I have had my starter motor done up and considering getting a four brush one built. Expensive but may provide the solution.
I have also had my cam timing (advanced I seem to remember, several years ago now) not ignition timing! to take load off the starter clutch as much as possible.
Plus I had the howdy sprag fitted, Now after it was in I was told it is not the one he builds because they dont fit the mille, but apparently it is out of a pontiac gearbox??? dont ask.
Anyway after the engine came back I unpacked it to find grit in the exhaust manifold, so being over cautious and checking inside the the cylinder for the mysterious grit, i upset the bevel timing. So there it has sat for a couple of years but I'm getting keen to get up and running.
So basically thats my story any help on the topic would be greatly appreciated.
If the suzuki 450, 500 have the same sprag then it just goes to show how much underdone Ducati engineered this one for a reasonably higher compression motor. Not forgetting this was the end of the line for Ducati before the bail out and so no improvements were forthcoming.
A pity seeing the rest is an awesome package.
Cheers
Scott