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My AF18
Posted: Mon Dec 10, 2012 9:45 pm
by Raindrop
Sup everyone .. name is raindrop and im trying to build a bad * scoot
heres what i got so far .. 2004 kymco zx which is a dio af18 engine
a 48mm bbk .. 24mm oko carb .. high performance varitior .. and dio v8 exhaust
what im asking you no it all's is what else should i get ? i wanna go like 50-55 cruise
but 0-55 i want fast .. like sprint fast .. please drop some info guys ..
is a 120 jet to big ? i have other jets .. ohh and oil has been blocked off
thanks ... your scoot lover raindrop
Re: My AF18
Posted: Mon Dec 10, 2012 9:59 pm
by Downsouthdio
Does your zx have aftermarket gears? What speeds are you reaching now?
Re: My AF18
Posted: Mon Dec 10, 2012 10:03 pm
by Raindrop
no just stock gears .. like 50 mph but not completely broke in yet ..
live in mi so its getting cold to ride .. started build in oct
but its gonna be 47 degrees fri so zoom zoom .. more testing
Re: My AF18
Posted: Tue Dec 11, 2012 11:07 am
by Raindrop
?? anyone else input ?
Re: My AF18
Posted: Tue Dec 11, 2012 12:01 pm
by Downsouthdio
I reccomend aftermarket gears.. It will keep your rpms lower so you arent constantly straining the engine, and you will gain more on the top end..
Re: My AF18
Posted: Tue Dec 11, 2012 12:12 pm
by knucks
Where in MI?
Re: My AF18
Posted: Tue Dec 11, 2012 12:16 pm
by tazland001
Get some gears raindrop. They are one of the most important part of any upgrade.
Taz
Re: My AF18
Posted: Tue Dec 11, 2012 2:18 pm
by Wheelman-111
Greetings:
Quoth DownSouthDio:
I reccomend aftermarket gears. It will keep your rpms lower...
This suggests you don't understand the concept of Continuously Variable Transmission, South. Steady-state cruising RPM will NOT be affected by the mechanical gears, but only by alteration at the Belt-Drive.
.. so you arent constantly straining the engine,...
The engine spins up at whatever RPM the belt-drive dictates, until the belt "tops out". By that time, a stock engine pretty much runs out of juice, (I can't believe the potty-mouth police deleted pee oh oh pee!) even with stock gears. High RPM operation doesn't "strain" the engine as much as lugging, when both lubrication and fan-forced air are scarcer. If lubrication and cooling are adequate, a two-stroke engine self-limits RPM as dictated by intake, porting and exhaust. Running wide-open all day is possible, 'til the fuel tank runs out.
...and you will gain more on the top end.
Once again, a kernel of truth but the statement misses the point. If the engine has the ponies to push faster than the stock gearing+belt "overdrive" allow, then yes taller gears will increase speed. If not, Nope, unless you find a nice downhill.
Re: My AF18
Posted: Tue Dec 11, 2012 3:05 pm
by Downsouthdio
He has a bbk.. Go ahead and run your zx with the stock gearing..
Re: My AF18
Posted: Tue Dec 11, 2012 3:40 pm
by kingkamehameha
Wheelman-111 wrote:Greetings:
Quoth DownSouthDio:
I reccomend aftermarket gears. It will keep your rpms lower...
This suggests you don't understand the concept of Continuously Variable Transmission, South. Steady-state cruising RPM will NOT be affected by the mechanical gears, but only by alteration at the Belt-Drive.
.. so you arent constantly straining the engine,...
The engine spins up at whatever RPM the belt-drive dictates, until the belt "tops out". By that time, a stock engine pretty much runs out of juice, (I can't believe the potty-mouth police deleted pee oh oh pee!) even with stock gears. High RPM operation doesn't "strain" the engine as much as lugging, when both lubrication and fan-forced air are scarcer. If lubrication and cooling are adequate, a two-stroke engine self-limits RPM as dictated by intake, porting and exhaust. Running wide-open all day is possible, 'til the fuel tank runs out.
...and you will gain more on the top end.
Once again, a kernel of truth but the statement misses the point. If the engine has the ponies to push faster than the stock gearing+belt "overdrive" allow, then yes taller gears will increase speed. If not, Nope, unless you find a nice downhill.
I was waiting for that. I kept my mouth shut in lew of the trollers on here. You pretty much nailed it. Im glad to know that there are people out there like yourself wheeldude who know the physics quite well. Gearing is misconcieved wrong by most. A cvt trans is tricky to wrap your mind around at first
Re: My AF18
Posted: Tue Dec 11, 2012 5:08 pm
by Wheelman-111
Greetings:
It took me less time than some. I grew up with Primitive Snowmobiles - like 1969-1973 Skiroules - and always marveled at how they seemed to find the right "gear" for every speed, incline and snow condition. Honda-san improved on those however, taking the clutch function away from the variator and isolating it within the driven pulley. You don't ever want to smell a drive belt melting from getting stuck if you can help it...
Re: My AF18
Posted: Tue Dec 11, 2012 7:20 pm
by Raindrop
ok so new gears .. what about clutch and springs ?
and i live in good old Roseville mi ..
like i said 48mm bbk and 24mm oko that * gas

Re: My AF18
Posted: Tue Dec 18, 2012 2:24 pm
by Raindrop
So what gears do i buy? and do i need to change crank.?
Re: My AF18
Posted: Tue Dec 18, 2012 4:21 pm
by Wheelman-111
Greetings:
The stock Honda crank is as durable as any, better than most. Leave it unless you have reason to believe it's worn or damaged.
8.44 gears for the setup you describe will give you the best compromise in acceleration, still able to reach 55+ if tuning is well done.
Re: My AF18
Posted: Tue Dec 18, 2012 5:59 pm
by Raindrop
Wheelman-111 wrote:Greetings:
The stock Honda crank is as durable as any, better than most. Leave it unless you have reason to believe it's worn or damaged.
8.44 gears for the setup you describe will give you the best compromise in acceleration, still able to reach 55+ if tuning is well done.
So do i search for 8.44 gears zx50 ? does taz have this for sale ..