Originally posted by RAIDER:
Anyone noes what this thing does? Does it spoil easily,how to prolong its lifespan? If spoiled better to buy new 1 or recoil? Lastly how much does it cost? Thanx guys!
the whole assembly is called an alternator (generator). as feng125 said, it generates power from your crankshaft's rotations and charges your bike's vital functions like battery, CDI etc, but that's after the AC current is converted to DC via the rectifier (mentioned in another post).
the magnetic part is attached to the crank-shaft, and the wire coil is stationary. also plays a vital role in spark timing. the electrical pulse generated is used to "tell" the CDI what position the piston is in (BDC, TDC, BTDC etc), and the CDI is programmed accordingly.
as for how to maintain, prevent damages etc, sorry man, i'm not that pro..

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