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lightening a flywheel

Posted: Mon Mar 09, 2009 8:43 pm
by 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

Re: lightening a flywheel

Posted: Mon Mar 09, 2009 10:21 pm
by 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............?

Re: lightening a flywheel

Posted: Tue Mar 10, 2009 12:00 am
by corrado
Stolen from another site......

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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.

Re: lightening a flywheel

Posted: Tue Mar 10, 2009 1:59 am
by 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

Re: lightening a flywheel

Posted: Wed Mar 11, 2009 4:59 pm
by 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".

Re: lightening a flywheel

Posted: Wed Mar 11, 2009 5:13 pm
by Bufficus
corrado wrote:Stolen from another site......

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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. ;)

Re: lightening a flywheel

Posted: Wed Mar 11, 2009 5:14 pm
by 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 ;)

Re: lightening a flywheel

Posted: Wed Mar 11, 2009 5:40 pm
by Bufficus
Supereibar wrote: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. ;)

Re: lightening a flywheel

Posted: Wed Mar 11, 2009 7:00 pm
by simon k
Supereibar wrote: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?

Re: lightening a flywheel

Posted: Wed Mar 11, 2009 7:32 pm
by 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....