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The DMF is actually designed so the engine can be driven at lower rpm.
They filter out torsional vibrations so the engine can run more smoothly at lower rpm, making the engine more efficient and help reduce emissions.
The usual result of using lower rpms is gear rattle and body boom but the DMF reduces that as the two masses which make up the flywheel are dampered by springs.
It's not driving at lower rpms that cause issues with them, that is a misnomer.
The main reasons they fail are excess heat due to clutch slip and abuse by engaging the clutch heavily or hamfisted gear changes that create massive torque spikes that are then transmitted through the sprung damper and bearing between the two masses, which is why they start to rattle (damper failure) then perhaps break up (bearing failure).
Parts have a life, even a solid flywheel can wear away. With a DMF, the sprung damper stops damping over time/use and the bearing can wear and become sloppy.
Obviously use isn't really measured in miles, it's gearchanges, heat and abuse.
If you travel 400 motorway miles at a time, everyday it will last far more miles than if you did 40 miles of stop start driving everyday and are perhaps hamfisted with your changes.
You can extend it's life by matching the gear with road speed as already mentioned.
When changing down it's easier to produce excess torque spikes by changing down to a lower gear when the road speed is still quite high, though it's still possible to create these torque spikes when changing up, badly!
As I wrote before, it'll happily chug about at low rpm, but trouble can arise when you don't and due to the way the Twinair revs, it's easy to want to thrash it.
They filter out torsional vibrations so the engine can run more smoothly at lower rpm, making the engine more efficient and help reduce emissions.
The usual result of using lower rpms is gear rattle and body boom but the DMF reduces that as the two masses which make up the flywheel are dampered by springs.
It's not driving at lower rpms that cause issues with them, that is a misnomer.
The main reasons they fail are excess heat due to clutch slip and abuse by engaging the clutch heavily or hamfisted gear changes that create massive torque spikes that are then transmitted through the sprung damper and bearing between the two masses, which is why they start to rattle (damper failure) then perhaps break up (bearing failure).
Parts have a life, even a solid flywheel can wear away. With a DMF, the sprung damper stops damping over time/use and the bearing can wear and become sloppy.
Obviously use isn't really measured in miles, it's gearchanges, heat and abuse.
If you travel 400 motorway miles at a time, everyday it will last far more miles than if you did 40 miles of stop start driving everyday and are perhaps hamfisted with your changes.
You can extend it's life by matching the gear with road speed as already mentioned.
When changing down it's easier to produce excess torque spikes by changing down to a lower gear when the road speed is still quite high, though it's still possible to create these torque spikes when changing up, badly!
As I wrote before, it'll happily chug about at low rpm, but trouble can arise when you don't and due to the way the Twinair revs, it's easy to want to thrash it.
)
