You can't use the original flywheel from your weedeater.
On this flywheel there are 3 magnets, you need only one.
Please be carfull with your new flywheel, the magnet must be tyd very strong.
You need also the same wight at the other side of the flywheel for balans.
Normal weedeaters have ~6 a 8000 rpm, with cdi 2 a 3000 more.
BTW, you need also exact the wight of your old flywheel for your new flywheel.
The engine need this wight to run smooth (contra wight for your cranck)
[link=http://www.jeroentune.nl/index%20introger.htm]tuning[/link]