Yes. I know I've posted a few times how my sprag clutch has been on the way out for 18 odd months but always started, well guess what's f**cked now! So it's new sprag clutch time, expecting £400 I haven't got just in parts. Seems big compression and big throttle bodies are putting a bit of strain on a known problem area. While trying to start though, bike electrics went from fine to everything goes off when I push the starter button, even using a good battery off my car. Now it's scratchy head time there unless there's some useful info on where to start looking. While I'm doing some work I'm going to beef up all the starter/earth wires, get a pin hole leak fixed in the radiator and possibly even change the coolant pipes to route them similar to RS bikes. Let's hope I get more time on this year than last, which was none :Bawling: Any info on the mods I'm planning or tracing the electrical fault would be appreciated. FWIW it's a race loom so there's no lighting or fan.
Just to confirm...yes, you are! No substitute for new parts when it comes to a starter clutch I'm afraid (from bitter experience).
So I've heard. And there was me thinking my bike's somehow magic powered and can't go wrong after the money I've spent on it. :Banghead:
Is your starter motor doing anything? I had a similar problem turned out the windings were burnt & shorting out which just immediately drained the battery, easy enough to remove & strip down for a look if you're getting at the sprag.
Might be worth a look. It's a bugger to start when cold so was trying for a while in short bursts. Then I noticed the cam pulleys just rocking forward and back a few mm. Presumed that the engine was top dead center and the clutch didn't have the grip to get passed it. Then I gave the starter button another prod and the dash went off and came back on when button released. So a burnt out starter motor shorting when tried does make a lot of sense
Yeah you could be lucky & there might be nothing wrong with the sprag, the slow demise might have been the motor packing in over a period of time, if it's gone like mine did it's pretty catastrophic & very obvious
I did consider removing the starter etc cos that should get me to a 1 BHP/KG power to weight ratio, but the impracticalities of it just don't make it a sensible idea.
Just an update. Pulled the starter motor out and stripped it to find this. A couple of the magnets had broken up inside! Thanks Tobytyke Quick fix was a new motor from Wemoto, great service. Half way through the coolant plumbing and already looking neater with only one hose left to fit. In the end I've just cleaned up all the terminals going to starter motor and ground so let's hope that's enough.
Spent days making a carbon T piece for the top coolant pipes and you can't even see it. Still, looks a bit neater now, and hope will look a bit better when I get some nice silicone hoses on it. FWIW, sprag clutch defo bolloxed. :Bawling:
Products – Freewheels, Backstops, Freewheel Clutches, Overrunning Clutches& (See the BWX Freewheel types)
You will need to tell them the exact dimensions etc of the sprag clutch you want. No good saying "I want a sprag clutch for X model Ducati".
Yeah I figured that looking on the site. Have saved a fortune in bearings through my life though by buying them like this. Let's just hope they can help. If it's not off the shelf so to speak it could cost more then standard. First is to get it out and check the damage.
Bit of an update on the sprag clutch. After getting the thing apart and actually not seeing the expensive wear I was expecting I found the sprag spring was really loose. I popped down my local bike shop, we tried a few oil seal springs but settled on a big ktm fork seal. £10 the pair. Fitted, tested, turns the bike over no trouble now. Whether the new spring is weak enough to release the clutch I won't know until I fire it up. Fingers crossed.
Thanks for the heads up Steve. With the advice of the forum I've now got a Clarke impact gun, cheap and awesome and the spring mod was mentioned here too of which I still have a spare. We used best judgement on spring size but my worry is it being too strong and turning my starter motor into an alternator and back frying the electrics. Should know before the weekend though.
Just to confirm, the spring from a 50mm fork seal seems to cure the sloppy sprag problem. Ran the bike up today and I've got no back voltage from the starter motor so spring can't be too strong to cause a problem. Result. Until it snaps next week gets chopped to bits in the gearbox then sucked through the oil pump killing that on its way to destroy the cams and every bearing it can get in to on the way.
