Dry clutch engine sproket / clutch gear lubrication question

What I want to know is... how is the engine sprocket and clutch gear
lubricated in a dry-clutch system like in many Ducati or Suzuki or
Honda race bikes?

With a wet clutch I presume the whole assembly just swims in oil... but
in a dry clutch arrangement you don't want oil all over your discs...
but the clutch gear is fixed to the back of the clutch basket, right
there, meshing with the engine sprocket, all in the same space...

Is wear on the teeth of the primary gear just not a big deal? Do you
cover the gears in grease and hope for the best? Is there some magic
lubrication system in there?

As a rider of a BMW with an inline single-plate dry clutch I don't have
experience with Ducatis and their maintenance. Also, I am not a
mechanic or I might just intuitively understand. This is something I've
been wondering about.

Thanks,

Chuck

 

Engine oil lubes the primary gears...

There's no "engine sprocket", the Ducks have a primary gear reduction
set up just like in a wet clutch system.

The whole idea of an oil bath clutch is to cool the friction disks with
engine oil. Early racing motorbikes had a very narrow power band and a
rather tall first gear. The rider would have to slip the clutch to get
moving...

Early roadracers would remove the kick starter to save weight. They
would push start the motorbike. They found that the oil bath clutch
resisted slipping and made starting more difficult. When they removed
the clutch cover and ran the clutch dry, they claimed that air cooling
was superior to oil cooling, since the clutch was exposed to air...

A long time ago in a world long forgotten, I walked up to to the late
George Kerker (yes, he invented the Kerker 4-into-1 exhaust system) in
the pits at a club race in Carlsbad, California. I said, "What'cha
doin', George?"

George was spraying chain lube on the primary drive chain of his
Norton.
He was running the wet clutch dry. George said, "This will be enough
lube for the short race I'm running in..."

Is a crankcase oil sump "magic"? No?

Go to www.partsfish.com and register.
Select the 998, 2002 model. Look at the Clutch fiche. You'll see #16 is
a
35mm inside diameter X 45mm outside diameter X 7mm thick oil seal...

Look at the Clutch Cover fiche. Item #6 is a 75mm X 95mm X 12mm oil
seal...

Those two lip-type seals keep the oil off the clutch plates.

 

The only BMW single I can think of with a dry plate clutch was
the R27 and its' ancestors. These did not have a primary chain.
The F650, best of my knowledge is wet plate. What are you riding ?

Unsure about Ducatis, but typically I think the primary chain would
run in a separate oil bath on bikes with dry plate clutches.

 

Ah-ha! Thanks Krusty for the pointer to partsfish... that'll come in
handy in the future. Maybe it will even allow me to expose my ignorance
in public less often...

What confused me is how the primary gear bolts directly to the clutch
housing... In the other diagrams I had been looking at I hadn't seen
the oil seals that allow the gear to be in a different (oil-rich)
environment than the clutch.

Chuck

P.S. Sorry for the confusion Rob, but I ride an R1200C. Dry clutch,
yes... sideways engine no...

 

It's an 1100 instead of a 1200, but you might get a kick out of

http://www.xmission.com/~wendell/R1100GS/

Should be very similar to the R1200.

Same basic engine/drivetrain setup as most cages.

 

Cool! And yes, very similar to the diagrams in the manual for my bike.