Ducati Monster Forum

I am considering this mod for my S2R.  What is the general consensus for mainly street riding?  I  believe I've found a DP one for the same price as the Nichols one, any real preference?  Thanks

This is one of those subjects that have generated a mountain of discussion via the search function.

I know I was kept busy when researching whether or not to use one with my M944SS build. I ended up going with the Nichols but would probably opt for a lightened stock flywheel over the ultra light Nichols if I had a do-over. It's an extremely dramatic mod for a street bike.

Do you like wheelies or not?  [evil]

Have the stock one lightened.

If there were someone close to me, I would have mine lightened.  What's your reasoning on going with a slightly heavier one than the Nichols?  And is there any difference between the DP offering and the Nichols and a lightened OEM?

Fast Frank sells lightened OE flywheels with no core exchange necessary last I checked.

This...

I sent my stock one out to Fox Performance to get lightened, then decided I wanted it lighter and got the sbk alternator adapter from Fast Frank Racing. Probably lost about the same weight as the Nichols, for more money. But, now I have a steel flywheel.  [roll]

Sooooo...from what I can decipher, the OEM lightened one is steel, and the Nichols and DP are aluminum.  Can anyone educate me as to why it is preferable to keep the lightened steel vs the aluminum?

this, to possibly avoid this,

(https://farm6.staticflickr.com/5454/14123349282_9464c0289e_o.jpg) (https://flic.kr/p/nw2RG7)20140304_104802 (https://flic.kr/p/nw2RG7) by DarkMonster620 (https://www.flickr.com/people/37973730@N08/), on Flickr
(https://farm6.staticflickr.com/5335/14126352415_ffdab109c8_o.jpg) (https://flic.kr/p/nwifqg)20140304_102200 (https://flic.kr/p/nwifqg) by DarkMonster620 (https://www.flickr.com/people/37973730@N08/), on Flickr
(https://farm8.staticflickr.com/7405/14126341475_d36152f6fa_o.jpg) (https://flic.kr/p/nwicaD)20140304_102005 (https://flic.kr/p/nwicaD) by DarkMonster620 (https://www.flickr.com/people/37973730@N08/), on Flickr
(https://farm3.staticflickr.com/2913/14146430883_0edbaff24f_o.jpg) (https://flic.kr/p/ny5a3K)20140311_151636 (https://flic.kr/p/ny5a3K) by DarkMonster620 (https://www.flickr.com/people/37973730@N08/), on Flickr

What is that a result of if I may ask?

the nut came loose . . . when installed I used Ducati specs, these were later revised and torque was increased to 270Nm instead of 190Nm . . . it was sweet, but now, I will go back to OEM since no more DP lightened flywheels available . . . if I get an OEM one, might send to ML for lightening to my specs . . . In the future to come . . .

and a lot of $$$ has gone into repairing it . . .a year after and between having no time and taking care of customers bikes, . . result is, bike is still on stands . .. 

They'll do it even if the nut isn't loose.

My theory is the aluminum expands and the flywheel can move back and forth on the splines the amount of the clearance between the two parts.

The aluminum can't take the battering.

Go with a lightened steel flywheel.

that was my case .  .  . I did hear about someone having similar issue of damage and nut WAS tightened . . .

That makes me want to take the case off of my bike and look now. I've had a nichols for going on 7 years and never saw any shavings in the oil. But considering I torqued to 150ft/lbs with red loc-tite, I never expected to have troubles.

Here are the torques:

 ALL, except below:   270N\m with Loctite 128455
 Panigale screw        160N\m with grease AGIP GR SM 2 
 MTS/DIAVEL/M1200  330N\m with Loctite 128455

Am I the only one with a Nichols flywheel that feels their cognitive dissonance kicking in right about now? Lol

I wanna say I was aware of and researched this issue before making the choice to go with a Nichols FW and was sufficiently satisfied that everything would be fine before taking the plunge. Doesn't Nichols MFG have an official response?

Ah ok now I remember...this only effects bikes with the newer 3 phase alternators.

Nichols is the only aluminum flywheel I would trust if I went with one again.

There are a few of the DP lightened aluminum ones available on eBay.  But if the risk is the use of aluminum, I'm steering clear.  Also, are the Fast Frank lightened OEM ones balanced after they are lightened?

there's no need.  as long as the lathe runs true they're fine.

maybe the dp ones are just the wrong material.  i've not seen ones tightened to 270 fail, but we only sold a few before we started machining the std ones after one did what is shown above.

I´ve had a Kämna Alu flywheel on my M900 for 45K+ km now, with no issues.
On the rain bike (900SS for rainy track days) I´ve lightened the stock steel flywheel, also with no issues. Pretty hard steel, btw.

In a few cases I´ve heard about where the nut loosened with std. steel flywheels the crank was ruined; there were quite a few of those some years ago. I think, with the loosened alu flywheel the crank was OK, but maybe the engine got all contaminated with alu bits?

The splines are of no use except for locating the flywheel on the crank, it´s held in place by the axial force from the nut. The splines take the beating only when the axial force from the nut is too low.

Theoretically, the axial force could increase with an alu flywheel as the alu heats up and expands. Might cause some deformtion due to repeated thermal cycling, and eventul loosening of the nut, maybe..?

Anyway, so far both flywheels are still in place, fingers crossed. 

10,000 miles and no issues.  Worth every penny if you like wheelies a lot.  ;D  Seriously, for me it was the second best mod I've done to my S4R