DMF - what's it like with a solid one?

[S0 What]

Fitted a few SMFs now and not one customer has really complained, in fact most say it makes the car feel quicker off the line (as Bchild says lighter flywheel) although one said it was easyer to stall, (again lighter flywheel lees stored energy?) i allways fit a sprung plated clutch to try and replace some of the absorbancy to clutch take up, even though the DMF is not designed solely for that reason i allways beleived it may have some effect on it.
I will add when testing the cars (manily mondeos and transits) i have felt the pulsing on the test drives but non of the cusomers picked up on it however i really feel that if the pulsing effect where to occure at say 70MPH in a relevant gear for motorway cruising some of the more adept drivers would pick up on it, where as i on the tests use gear and rev combinations most owners would never use or for the same amount of time.
TBH i've allways noticed the pulsing, mainly on larger 4 pot diesels, all my old Di transits did it but then i did used to spend 14 to 20 hours at a time in the dam things so maybe simply looking for it makes it easyer to spot? you need to really be in tune with your motor to notice and lets face it 90% or drivers are not at all.

Edited by S0 What on Saturday 14th July 21:42

[y2blade]

mad4amanda said:

Garage I use all the time will now not replace a dmf with solid after having issues with gearbox damage to bearings blamed on the undamped vibration from the engines powerstroke.
LUK make good replacement DMF .

this^^^

[MGJohn]

The K18 in my MG ZS 120 is the same as that in a 1.8 normally aspirated Rover 75. The latter has a DMF, the former does not.

Very interesting ....

http://www.youtube.com/watch?v=SQyUKnCf0YY

.... but stupid ...

[MGJohn]

y2blade said:

mad4amanda said:

Garage I use all the time will now not replace a dmf with solid after having issues with gearbox damage to bearings blamed on the undamped vibration from the engines powerstroke.
LUK make good replacement DMF .

this^^^

A garage would I assume have to guarantee their work so should adopt a belt and braces approach with that always in mind. I as an amateur but experienced spanner operative .. ... would not have such reservations when working on my own cars. The DMF fitted to the 1.8 R75 was a LUK unit. You can see their logo in this picture of it :~

[MX7]

B'stard Child said:

SMF's are normally lighter - that would give rise to the comments you've seen - lighter = less flywheel effect

Yes, obviously, but i presume that the people who complain about the conversion have selected a like-for-like flywheel, although someone earlier on this thread did cite examples where a Helix performance flywheel was fitted as an example of how bad a SMF can be.

Even with a petrol engine a lighter flywheel can cause all sorts of problems.

B'stard Child said:

IF the weight is identical then the result should be very similar - but if you are replacing a DMF then SMF is normally by consequence lighter

I presume that the manufacturers of the drop-in conversion kits make sure that the flywheel is heavy enough to give a similar experience.

[B'stard Child]

MX7 said:

B'stard Child said:

SMF's are normally lighter - that would give rise to the comments you've seen - lighter = less flywheel effect

Yes, obviously, but i presume that the people who complain about the conversion have selected a like-for-like flywheel, although someone earlier on this thread did cite examples where a Helix performance flywheel was fitted as an example of how bad a SMF can be.

Even with a petrol engine a lighter flywheel can cause all sorts of problems.

I'm not sure there are many like for like DMF replacements

MX7 said:

B'stard Child said:

IF the weight is identical then the result should be very similar - but if you are replacing a DMF then SMF is normally by consequence lighter

I presume that the manufacturers of the drop-in conversion kits make sure that the flywheel is heavy enough to give a similar experience.

And I'm not sure they do......