[uRban-x]

hey guys,
My name is Ananth and i have a Thunderbird Twinspark UCE (Carb. version).
yesterday i was riding my bike and suddenly just after taking a 'u' turn my bike started making a weird, LOUD, continuous, "Trrrrrrrrrrrrrrrrrr" noise from the clutch casing side.
I pushed it to the service center here and they told me that is might be the sprag clutch issue. The thing that puzzles me is that the bike has no starting issues at all.. 
If it is the sprag clutch issue, is it worth getting the expensive replacement done ? or should i just get rid of it and live with the kick start. ?

Advice me please !

PS: This is my first post.

Thanks in advance,
Ananth.

[Ducati Scotty]

When the sprag fails it usually just makes noise when you try to use the electric start.  I don't think it's the sprag.  It could be that the auto chain tensioner for the primary chain has failed and there is too much slack in the primary chain.  Don't ride it like that, it could cause damage.

No matter what it is take the side cover off and have a look.  That may tell you what's wrong right away.

Scott

[uRban-x]

I will take a look ASAP. does the side cover have engine oil inside it ? should i drain the oil before i open the cover ?

[Maturin]

The clutch is located behind the left cover, so there will be oil. I'm not sure if it's necessary to drain completely though, but as it's 2L as maximum just put a big pot underneath, maybe you can save some oil this way. Don't forget either to get a new gasket first, or to be very carefull to preserve the old one.
Concerning the noise: another possible origin is the clutch, f.e. a broken spring or plate. In this case switching gears would be impaired, or clutchb drag would occure. Anyway, most failures should be quite obvious. Good luck & regards

[uRban-x]

The tensioner was the culprit. It had failed somehow, needed little tweaking.
now the problem is putting the cover back. The existing gasket is not in a good shape.
can i use a gasket maker paste ? say Loctite ? :O

[Ducati Scotty]

Well done on you first repair!

Better to get a gasket if you can.  If not, some high temp RTV silicon used VERY sparingly.  Just a hint along the edge is all you need.  Any excess gets squeezed into the oil, nobody wants that.

Scott

[Maturin]

Well done uRban-x, and well diagnosed Scott!
A decent emergengy repair is to use the old, fringed gasket and patch the broken parts with a SMALL amount of sealing paste. As this point the cover does not have to take much oil pressure, so it should hold tight - more or less. If you´d like to create a stable solution though, you should wait for a new one.
What exactly was wrong with the tensioner? Would you mind taking a photo? I didn´t pull the left cover yet and am curious
Regards

[Ducati Scotty]

Maturin's solution is less messy than mine and less apt to clog things up.  Patch the gasket if you can.

Scott

[Ducati Scotty]

Well done uRban-x, and well diagnosed Scott!

I post a lot.  Something I write has to be correct sooner or later just based on volume

[uRban-x]

I post a lot.  Something I write has to be correct sooner or later just based on volume

Its only because of the same that we all get our doubts clarified very fast