LIGHTWEIGHT FLYWHEELS FOR DUCATI MODELS ***UPDATED***
A modification aimed at those who need a little more response and drive out of corners, this works well on bikes that see the track or fast work on twisty roads often. The reduced rotating weight of the engine lets the engine and therefore the rest of the bike accelerate a little quicker. Coming out of turn 12 at Phillip Island is a good example, where good speed down the straight is based on drive out of this corner.
The new alternator design that came with the 1998 onward model bikes is quite a bit heavier than the older design, with all that weight spinning on the end of the crank. Although we can’t do anything with the alternator magnet assembly, the flywheel which mounts the magnet to the crank can be machined down or replaced with an aluminium replica. The standard flywheel on all the fuel injected bikes ( 2V and 4V ) weighs approximately 1900 g. We have machined them down to 990 g, with an aluminium replica from Ducati Performance coming in at around 660 g. Quite a big difference.
****UPDATE : We have unfortunately had an issue with the Ducati Performance lightweight flywheel that makes me withdraw my recommendation of its use in the post 98 models. These models have the late alternator set up, where the flywheel is splined onto the crank. Although the lightweight flywheels are hard anodized aluminium, the alloy splines that locate on the crank may not be up to the task. One we fitted to a 996 has stripped out the splines, letting the flywheel spin around the crank. In itself, this was not a big issue, as the nut was still tight and the bits of alloy taken off can’t get out and into the engine.
The issue is that these Ducati Performance parts come with no warranty. None whatsoever. This flywheel is not very old, and the man who paid for it is not altogether happy about having to pay for a replacement. I will certainly not fit any more. For this bike we will fit an original steel flywheel that has been machined down to around 900 grams. Still a reduction of nearly 1 kg, and only 250 or so grams heavier than the alloy piece. For these late alternator models we will recommend this is the future, or an aftermarket piece that uses a steel centre section. The STM piece fits this description, and is around $350.
The older flywheel outer from the 748/916 model is much heavier. This can be removed totally on these models, making a big difference to the response and the feel of the engine. Enough to make them somewhat annoying around town with the increase of engine braking and the way the engine wants to stall sometimes. Okay once you get used to it, but that depends on what you deem acceptable. An aluminium replica replacement is available to put some weight back on if needed. Just costs some more
The ‘98 onward models can only get rid of about 1300 g at most. This makes less difference than I was expecting ( dreading ), given problems we have had in the past with another model. There is none of the negatives that comes with the 916 mod described above, just more response to throttle opening. For those whose riding style and usage can take advantage of the increase in response, the benefits will be very obvious. For those who don’t use the throttle hard and often ( we need to be honest here ) or need to come out of corners hard, it may not be worth the expense. The flywheel is around $300 to buy, plus a couple of hours labour to fit. Not cheap to many people. It just depends what your priorities are.
As the flywheel on the carby models carry the signal lugs for the ignition pick ups, removing the flywheel outer is not an option here. Aluminium replacement flywheels are available from Ducati Performance and other sources to suit these models. For a bike such as a Superlight that can never carry a passenger, a lightweight flywheel is a real performance addition. Suitability of this mod, once again, really depends on the type of riding you do.
