The top ten differences between AF18 and AF16 motors

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The top ten differences between AF18 and AF16 motors

Post by sanjuro » Sun Jan 15, 2012 10:40 pm

I get this question all the time so finally decided to post the answer here for all to see. Maybe some of the 808 crew can chime in.

1.) af18 right side case has the pulse generator at the front
2.) af18 uses the '87 elite se50 flywheel and stator
3.) af18 left side case has a vacuum nipple at the front (this is to faciltate the fuel pump for floorboard mounted fuel tanks)
4.) af18 uses a different right side fan shroud because of item number one listed above
5.) af18 intake tract openings are hollowed out more below the reed block
6.) af18 boost port is barely larger than an af16 (I've examined five bone stock af18 motors to confirm this and have one virgin left side case straight from the factory parts warehouse in Japan)
7.) af18 utilizes a different airbox
8.) af18 has different part numbers for the crank, piston, cylinder head and jug
9.) af18 uses a different exhaust (Dio ZX used an upgraded Goshi exhaust)
10.) af18s on ZX scoots have larger diameter pulley sheaves

I have never bothered to find out if the carbs are different, but I'm assuming they are. If you are using a gravity fed fuel system there's no reason to run an af18 over the af16 as-long-as you use an after market cylinder kit. That's all I know.


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Re: The top ten differences between AF18 and AF16 motors

Post by Wheelman-111 » Sun Jan 15, 2012 10:44 pm


Great stuff, Sanjuro. Moved to Documents for Posterio-ity.
Most of my money is spent on scooterparts. The rest is just wasted.
Still Seeking Red PCX-150
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox, Carb and Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 99KPH


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