lightening a flywheel

[simon k]

i want to get a gp electronic one turned down on a lathe anyone got any pictures or measurements i can pass on to the machinist?
and is it best to remove the magnets first?
thanks in advance. Simon

[sean brady scooters]

theres really no need to remove magnets...............whatever you do..........
also.......do you intend to keep ally fins.........or are you going to use a plastic/nylon fan set up.........?
the actual lathe work would differ ,depending which way you go...............
and also as too how much you would like to remove.....................
what weight would you be aiming for simon............?

[corrado]

Stolen from another site......









One thing I would suggest is to mask off as much of the magnets as you can as it'll make all the swarf much easier to remove afterwards.

[simon k]

thanks for that Corrado.
yes Sean i plan to fit a nylon fan from beedspeed and have the final weight around the 1.9kg mark. would this require more meat taken away from the lip where it joins the fan?
cheers Simon

[corrado]

I've never weighed the alloy fan piece on it's own but should imagine it's fairly light anyway, I'd imagine that you need to remove as much steel / iron from the main body of the flywheel to significantly save weight. The plastic flywheel on the feckspeed racer only lasted a handful of laps before saying "Adios amigo".

[Bufficus]

Stolen from another site......









One thing I would suggest is to mask off as much of the magnets as you can as it'll make all the swarf much easier to remove afterwards.

That looks like suspiciously like my hand and my computer desk.

[Supereibar]

Wouldn't it be easier to just buy an AF one? You will save money and you will save a piece of history... JUST my humble opinion of course

[Bufficus]

Wouldn't it be easier to just buy an AF one? You will save money and you will save a piece of history... JUST my humble opinion of course

Some people consider them to be too light at 1.4kg and some consider them to be too crap because of the amount of fiddling about some seem to need.

[simon k]

Wouldn't it be easier to just buy an AF one? You will save money and you will save a piece of history... JUST my humble opinion of course

i hear what your saying Supereibar but i gave up on the easy option and saving money when i said yes to lambrettas
a friend will do the lathe work for a beer, £10 for a fan & it already fits my set up without fettling.
as for history its a newish indian 12v flywheel so.....
what weight you running Bufficus?

[J1MS]

The alloy fan is alot lighter than it looks, and IMO more reliable than a plastic one ..... Ive machined a couple of flywheels in the past (Indian). Did one for a mates race scoot back in the early 80's removing all the magnets.... With the fan removed I showed it to him, he said not much weight reduction there and it fits better than the plastic one put it back on.....They really are quite light....