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Flywheel machining

Posted: Thu Sep 19, 2013 3:04 pm
by idc1967iow
If get a machine shop to lighten a flywheel will it need balancing after?

Cheers Ian :|

Re: Flywheel machining

Posted: Thu Sep 19, 2013 3:15 pm
by dapper
It would be worth doing to cut down on vibrations and stress on the crank.

Re: Flywheel machining

Posted: Thu Sep 19, 2013 6:09 pm
by camel
machine it on a crank held in a lathe and centres all running true,probably as good as your going to get...thats how i do mine
how can you balance a flywheel?

Re: Flywheel machining

Posted: Thu Sep 19, 2013 6:25 pm
by ducksta
what scoot

Re: Flywheel machining

Posted: Fri Sep 20, 2013 10:29 am
by dapper
how can you balance a flywheel?[/quote]

Well, they obviously do 'cus there's lost of little holes drill together on some flywheels where they remove weight to balance 'em. :)

Re: Flywheel machining

Posted: Fri Sep 20, 2013 3:57 pm
by Grumpy225
camel wrote:machine it on a crank held in a lathe and centres all running true,probably as good as your going to get...thats how i do mine
how can you balance a flywheel?

It's a specialist job where they spin the flywheel at some high speed and detect where the inbalance factor on it is. Kinda lika balancing a wheel but more high tech.

When I had all the fins shaved off an AF flywheel I had to have it rebalanced. My machinest made a special mandrel to match the taper of it and the balance shop did their magic on it. When it came back there were new holes in it for balancing.

Re: Flywheel machining

Posted: Fri Sep 20, 2013 4:56 pm
by camel
sounds easy
balancing flywheels is obviously more common than i thought!

Re: Flywheel machining

Posted: Fri Sep 20, 2013 5:14 pm
by oggy
Hi,made a ss cover for my cowling,but the fixings inside the cowling foul the flywheel,there 5mm nylocs,can i have that much machined of safely without a cooling issue,thanks.

Re: Flywheel machining

Posted: Fri Sep 20, 2013 9:40 pm
by Ihateyoubutler
In my humble opinion, balancing anything that rotates is only ever going to cause less axial or radial movement at certain rotational speeds (vibration). To "balance" a flywheel, and to be effective across the total rev range of even a standard Lambretta engine, never mind the increased rev range of a tuned engine, might be difficult to achieve. What I'm suggesting is that it will only be "balanced", ie causing less vibration, within a specific rev range anyway. If a flywheel is machined to run smooth at, say 5000 rpm, it doesn't mean it will do at 3000 rpm. Maybe a flywheel should be machined so the engine run as smoothly as possible at the constant speed the engine is generally run at, but in this country and on our roads would this be possible?

Re: Flywheel machining

Posted: Fri Sep 20, 2013 10:34 pm
by idc1967iow
Interesting :?