Why dry clutch?

[russell_bynum]

I have the 04 GT and have gotten used to the typical box of rocks sound with the clutch out. Not as pronounced as the Ducati but it's definitely noticeable

 

That's not the clutch, it is the transmission.

 

The clutch on a Ducati rattles when the clutch is IN. It's a multi-plate dry clutch (vs. the single-plate dry clutch like a Boxer/Flying Brick) and the sound is the plates rattling around. With the clutch is out, the plates are pressed together by the springs and there's no rattle.

[Paul Mihalka]

There may be a confusion in this thread, when is a clutch "in" and when is it "out"? "engaged" or "disengaged" would be clearer. I am confused.

[ShovelStrokeEd]

Ducati clutch plates rattle against the basket when the clutch is disengaged.

 

BMW transmission input gears (on older machines) rattle when the clutch is engaged.

 

Two entirely different sounds from two different sources. I never understood the idea that a Ducati clutch sounds good. I always equate that noise with a bearing gone bad. I hated the sound on both my Pasos and my 900SS. Not to mention I couldn't keep a throwout bearing in the 906ie for more than about 1000 miles.

[dirtrider]

I have the 04 GT and have gotten used to the typical box of rocks sound with the clutch out. Not as pronounced as the Ducati but it's definitely noticeable

 

That's not the clutch, it is the transmission.

 

The clutch on a Ducati rattles when the clutch is IN. It's a multi-plate dry clutch (vs. the single-plate dry clutch like a Boxer/Flying Brick) and the sound is the plates rattling around. With the clutch is out, the plates are pressed together by the springs and there's no rattle.

 

Afternoon Russell

 

Actually on the Ducati dry clutch it rattles more with the clutch plates clamped together as the rattle is in the steel plate drive ears to the clutch drum slots. Not that it matters as they will rattle about as bad with the clutch disengaged also.

 

There is a (somewhat) FIX for the rattle by adding another thin clutch plate to force the first metal plate deep into the U shaped bottom of the clutch drum slot but most Ducati riders like and want the clutch rattle.

 

I know if I fixed mine then I couldn’t wear my Tee shirt that says “Loud Clutches Save Lives”

 

 

 

 

[russell_bynum]

There may be a confusion in this thread, when is a clutch "in" and when is it "out"? "engaged" or "disengaged" would be clearer. I am confused.

 

I'm more confused than a dog in a hubcap factory.

 

I was using "In" to mean that the lever was pulled in and the clutch was disengaged. "Out" meant that the lever was released and the clutch was engaged.

 

 

[TowJam]

I was using "In" to mean that the lever was pulled in and the clutch was disengaged. "Out" meant that the lever was released and the clutch was engaged.

+1

 

(I am but a simple man. Such fancy terms such as "engaged" and "disengaged" frighten and confuse me.)

[SuperG]

I am really loving the fact that the engine, clutch and trans does not take a bath together (in the same oil). And the engine get 4 quarts of dedicated oil...all to it self.

Yeah this is a selfish kinda engine:)

 

I had about 20 other bikes in the past 30 years and all were wet clutch. This is my first dry bike ...YEAAAHHH !

[VinnyR11]

 

Let's compare the two bikes for a bit.

 

Harley - wet clutch, huge flywheel mass (often mistaken for lots of low end torque)......(my highlights)

 

BMW - dry clutch, very low flywheel mass relative to bike mass,....

 

I think Ed's point above, stated within a longer post, may have been overlooked a bit. Flywheel mass is critical when assessing "clutch feel". IMHO, flywheel mass has a much greater impact on clutch feel than whether it is a wet or dry clutch.

 

Flywheel mass is one of the trade-offs in vehicles. Aside from the overall weight savings , for the most part, lighter and it spools faster, heavier and you get smoother launches and it can smooth out driveline slack during on-off throttle transitions.

 

I'm guessing that one of the biggest difference between Harley and Beemer low rev launches and how you need to apply the clutch is the difference in their flywheels and not whether they have wet or dry clutches.

[CoarsegoldKid]

There may be a confusion in this thread, when is a clutch "in" and when is it "out"? "engaged" or "disengaged" would be clearer. I am confused.

 

Paul I know you know this but for clarity on these terms when the clutch is engaged power is transmitted from engine to trans by way of contact between pressure plate and flywheel. The hand lever is out and you are moving under power. Pulling in the lever disengages the clutch pressure plate from the flywheel where it no longer transmits power to the trans and you are coasting or idling or shifting gears.

 

 

Why a dry clutch? ON racing bikes it is easier and faster to swap out. ON the BMW boxer it is easier to deal with in every way shape and form.

[ShovelStrokeEd]

Hey Vinny! Head on over to the thread on torque over in the Hexheads forum and 'splain it to them. I've tried 2x and they just aren't gettin' it.