Are flywheels getting too light?

[mk1]

The evidence would suggest that they probably are!

This is an MED X-Lite that has done just a light couple of seasons in my Hillclimber, TBH I was pretty shocked when I saw this!

I have emailed the pics to MED & will post any developments here.

M

[snoopy64]

Wowzers… what material was that supposed to be?

[Mini-geek]

Maybe it's has more to do with the supplier

[Exminiman]

ooh dear, does look a bit fried...what does the backplate plate and clutch plate look like ?

Wondering if the backplate plate and flywheel contact surfaces are not completely aligned, causing slipping ?

The ears (raised bit for bolts ) on backplates are not aligned, height wise, these days

[mk1]

MED steel backplate, sintered clutch, grey diaphragm.

Clutch plate is OK, backplate is perfect.

All balanced, worked perfectly, no discernible slip.

[Oneball]

I’ve got their ultra-light flywheel. Had it on the 1 litre first now on the 1275 so it’s probably done 10 seasons. It looks nothing like that.

[Exminiman]

Not sure then, does look as if its getting really hot though - not sure what would cause that except slip or maybe incorrect material ?

[Oneball]

Is the colour change on the spokes from heat treatment in manufacture or is that from use?

[GraemeC]

Wow - that's the worst I've seen!

My experience is that lightweight flywheels are no use on anything that demands many standing starts or heavy clutch use. Race applications only really.

The lack of mass in the flywheel and backplate just can't absorb and then dissipate the heat generated from grippy clutches and strong diaphragms. Generally the backplate suffers worse as it can't sink its heat into the crank like the flywheel.
I'll bet my equally fubared flywheel that your backplate is warped and that, if tested, you're not getting the holding force that a grey diaphragm should be giving you. (The problem starts with the strong diaphragm bending the backplate giving hotspots adjacent to the horns that then grip first).

I now use the MS roadweight 22A598 backplate and it is much better than the lightweight ones in surviving the abuse.

[Pandora]

I don't know, but I'd say that's from Adam, not you

Al