Some more numbers I dug up. Looks like the Supersprox stealth 520 is near stock weight of the 530, or heavier if you add teeth. That seems surprising I would want to weight my stock 530 to verify that. The Driven aluminum 520 should be comparable to the other aluminum sprockets, although there is probably more to the story as far as hardness toughness etc. The
AFAM Workslite is the lightest I have seen so far .57 LBS for 44T 520. Looks like the Renthal ultra light steel front sprocket is the way to go, lighter than the AFAM chrome-moly.
BST/Marchesini/OZ Sprocket Type
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Afam Workslite Rear Sprocket 520-43 = .64 LBS
Afam Rear Sprocket 520-43 = .72 LBS
Driven "Alum" Rear Sprocket 520-43 = .71 LBS
Superlite Black Steel Rear Sprocket 520-43 = 1.5 LBS
Superprox "Stealth" Rear Sprocket 520-43 = 1.47 LBS
GSXR750 Sprocket type
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stock steel 525 45T = 1.72LBS
Renthal aluminum 520 45T = .74 LBS
stock steel 525 17T front sprocket = .581 LBS
Renthal ultra light steel 520 16T front sprocket = .309 LBS
1000RR Sprocket Type
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Stock steel 530 42T = 1.34 LBS
Supersprox Stealth 520 45T = 1.43 LBS
AFAM 520 44t Workslite Hard Anodized Rear Sprocket=.569 LBS
Stock 530 16t Front Sprocket= .6 LBS
AFAM 520 15t Chrome-moly steel drilled Front Sprocket=.415 LBS
Stock 1000RR 530 DID chain 116 = 5.1 LBS
DID 520 ERV3 chain 118 = 4.0 LBS
EK 3D GP 520 chain 114 = 3.85 LBS