APTC Clutch
 

New Slipper Clutch

If you’re in the market for a new clutch, you might want to consider the new Adler Power Torque Plate Clutch (APTC) that Ducati is now installing on the Monster 620 at the factory. It’s a slipper clutch which is suposed to work better than the present ramp and ball slipper clutches but with a 40% reduction in clutch lever pull.

It’s offered with steel friction plates for (2001 and earlier model) Ducatis or with aluminum plates for (2002 and later) models that use an aluminum clutch basket. About 1079 Euros.

http://translate.google.com/translat...lr%3D%26sa%3DN

neat;)

So the M620i clutch is dry, now?

I'd wondered why Ducati were fitting a slipper clutch on an entry-level, road-use bike.

Is it because they think it'd be easier for inexperienced riders who can't do a smooth down-change on a "proper" clutch? :roll:

Ouch! lol 'proper clutch'

:lol::lol::lol:

Doncha just love web based translation....

Anti Hopping: this effect prevents that rear wheel temples, which can occur when applying brakes gently and simultaneous shifting down. A dangerous phenomenon, since the rear wheel loses clearly at strassenkontakt, and the straight in the delicate phase at the curve entrance!

An anti Hopping system contributes therefore on the one hand to security, made possible on the other hand in addition, faster and brisker cornering with reduced risk. The feeling to feel even when hard shifting down no marking and no winding the engine up makes straight addicted!

Reduced hand strength: Anti of Hopping systems gives it several, but only the eagle system offers owing to a special pressure plate (power torques) also reduced hand strength. Simply spoken the clutch takes a part of the strength, which is needed for coupling, of the engine strength, which rests anyway permanently against the clutch. And only the hand strength must contribute a further part!

Technically seen over a helical gearing one realizes, which supports the clutch manipulation. In further consequence softer clutch feathers/springs can be used and one keep a many more low-friction kupplungshebel simply ingeniously, ingeniously simple - and in the use the hammer!


:lol::lol::lol:

Still, I like the last bit about the use of the hammer, I always try to wait until I've negotiated the straight in the delicate phase at the curve exit before I give it some hammer

As far as I can tell, all the new clutches (620 & S2R) are WET APTC, not dry. Ducati does indeed claim this is for safety reasons for inexperienced riders. Appears to be torque related - more torque, stiffer clutch action but at filtering speeds, light action. Don't know how they do it tho.

I'm impressed you guys understood any of that gibberish. I gave up about half way through...

I'm actually looking for a slipper clutch for my 998R. I had more or less decided on getting the DP (Bucci) racing slipper clutch (968317AAA) but considering it's quite pricey I wouldn't mind cheaper alternatives.

Would you say I'd be able to install one of these APTC ones instead? :puzzled:

Found this on another website somewhere, so it looks as if the clutch has this feature that makes the amount of torque it transmits independant of the spring pressure. Under those circumstances I can't see what's stopping it being used for any Duke. I think it's still a dry clutch (obviously the one in the picture is) but i don't know if they also do wet versions.

Apparently it's designed in conjunction with Ducati (but also seems to be making appearances on off road bikes - so probably not exclusive to Ducati who's only design input would probably be to make it suitable for their own bikes)

The APTC clutch
The newly developed clutch -named the APTC (Adler Power Torque Plate Clutch) –used on the 2004 Monster 620 and 620 Dark is patented and designed by Adler, and developed according to precise specifications by the Ducati R&D Department. It is a clutch with follow-up torque: this means that the torque transmitted is always a function of the torque applied to the device. This feature has made it possible to dramatically reduce effort required to disengage the clutch via the clutch lever, while still ensuring excellent operation and high dependability. Thanks to the APTC device, the torque transmitted is increased significantly compared to that of a conventional clutch, without having to increase the size of the clutch itself. Another important characteristic is that the system automatically limits back torque that is generated during heavy braking and down shifting, avoiding rear wheel skidding. In addition to these obvious advantages, the APTC clutch does not require did not require any adjustment or changes to the original clutch case or the primary drive system.

Design objective
The R&D Department at Ducati has worked alongside Adler R&D to develop an innovative clutch, in line with the new technological and performance-related goals of the modern Desmodromic Ducati engines. The objective was to obtain high torque, without increasing the size of the clutch, and simultaneously achieving more control and lower handlebar clutch lever effort. A unique technical solution has allowed the creation of a clutch in which the transmittable torque is, in part, independent from the pressure of the clutch springs. In a conventional clutch, with the same size discs and made from the same material, the transmittable torque can only be increased if the pressure of the helical springs that act on the pressure plate is increased. However, increased spring pressure creates a negative effect, as the effort required at the handlebar lever is also increased.

Eliminating the risk of “back torque” and rear wheel skidding

If you approach a turn at steady speed and you downshift a number of gears in rapid succession, the moment you release the clutch lever, rather than the engine driving the rear wheel, the opposite occurs and the rear wheel is driving the engine. In this case, the torque is not transmitted from the crankshaft to the rear wheel, but the exact opposite occurs. In this situation, the torque is technically defined as back torque and it is a characteristic of twin engines in particular, which possess strong engine braking.

The effect of this phenomenon is twofold:

The rear wheel of the motorcycle tends to skid and consequently loses traction.
The engine is driven faster and risks potential over-revving.
With the APTC device, Ducati has eliminated these two risks.

Less pressure
The same torque
The APTC clutch used on Ducati engines of 620cc and greater has allowed a reduction of the diameter of the clutch discs from 150 mm to 140 mm, and considerable volume reduction. At the same time the effort that must be applied to compress the helical spring of the pressure plate has been reduced from 860 N to 560 N, while the maximum torque that can be transmitted (9.98 Nm) remains the same as in a conventional clutch. The lighter pressure helical springs, which act on the clutch pressure plate, produce notably lower effort required at the handlebar clutch lever, and consequently improved clutch control. In addition, the effects of the back torque, rear wheel skidding and the tendency of the engine to over-rev while going down the gears have been brilliantly eliminated.

Just checked spec on Ducati site - 620's are definitely wet clutch.

The url to Adler s.p.a (the producer) is http://www.adler.it/index1.php?lingua=eng but unfortunately there isn't much useful info in English :(