Looking for 70cc polini big bore advice

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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maddog
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Re: Looking for 70cc polini big bore advice

Post by maddog »

Hey Kona, been running the stock pump for 17 yrs. i can tell you that the stock pump gives out at 50,000 mi. so i replaced it with a sym pump at 1/3 the cost, just have to swap out the shaft, at 76,000 mi. i still beat the crap out this engine with a 44.7mm crank = 76cc polini :smile:
some people dream of speed, i own your dreams!
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kingkamehameha
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Re: Looking for 70cc polini big bore advice

Post by kingkamehameha »

Nice to hear from you maddog. I still wouldnt reccomend using the stock pump
ua mau ke 'ea o ka aina i ka pono o hawaii
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paulpauly7
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Re: Looking for 70cc polini big bore advice

Post by paulpauly7 »

on yahoo auctions japan you can buy a new modified oil pump for the af18 that pumps 1.5 times more oil than stock ideal for bbks without the hassel of premixing
86 Nifty Fifty (spree)
ZX disk brake
Kitico 120kmh speedo
AF18 ZX ported
Polini corsa
Malossi crank
CTmani
24mmOKO
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veedubh20
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Re: Looking for 70cc polini big bore advice

Post by veedubh20 »

oil pump plug are better , no hassle! :2thumbs:
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scottinscotty
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Re: Looking for 70cc polini big bore advice

Post by scottinscotty »

oil plugs equal.. to much hassle at the gas pump! i think pre-mixing hide's poor carb jetting skills! :geekdance:
72cc polini contesa kit
oko variator with 8.5 gram malossi weights
21mm Black Oko Carb & Ct Manifold
8.44 gear
malossi MHR exhaust
Dio zx trans conversion
1000 center spring
1500 grabbers
sef ramp plate
B9hs plug
GPS 60mph
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kingkamehameha
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Re: Looking for 70cc polini big bore advice

Post by kingkamehameha »

scottinscotty wrote:oil plugs equal.. to much hassle at the gas pump! i think pre-mixing hide's poor carb jetting skills! :geekdance:
You must be mentally challenged if you cant add 4oz of oil to a tank. In my case i can only put half a gallon at a time so 2 ozs is pretty quick
ua mau ke 'ea o ka aina i ka pono o hawaii
mmeadows
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Re: Looking for 70cc polini big bore advice

Post by mmeadows »

scottinscotty wrote:Taped a second hole.... I've put almost 2000 miles on my kit with the stock oil pump...

can we see a picture of this mod? think it would work on a af05 with bbk?
84 Aero af05e Ruckus variator, rear metro wheel, Leovince pipe ( work in process... porting , nh80 reeds intake carb)
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Trafficjamz
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Re: Looking for 70cc polini big bore advice

Post by Trafficjamz »

some oko carbs have the oil injection port built in.

I have a 28 mm carb that has it.
scottinscotty wrote: i think pre-mixing hide's poor carb jetting skills! :geekdance:


That make zero sense :crazy:

Premixed two stokes are not any easier to jet :*:

How do you deal with the split throttle cable to the oil pump? Do you just tie it open?
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
mmeadows
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Re: Looking for 70cc polini big bore advice

Post by mmeadows »

Trafficjamz wrote:some oko carbs have the oil injection port built in.

I have a 28 mm carb that has it.
scottinscotty wrote: i think pre-mixing hide's poor carb jetting skills! :geekdance:


some oko carbs already have two oil injection ports? so do you then just connect the the two ports to the one oil pump barb, and this somehow gives you a better ratio? why its still the same oil pump?

stock oil pump = extra trunk space and less hassle so i really want this to work but don't fully understand it.
84 Aero af05e Ruckus variator, rear metro wheel, Leovince pipe ( work in process... porting , nh80 reeds intake carb)
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Trafficjamz
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Re: Looking for 70cc polini big bore advice

Post by Trafficjamz »

mmeadows wrote:
some oko carbs already have two oil injection ports? so do you then just connect the the two ports to the one oil pump barb, and this somehow gives you a better ratio? why its still the same oil pump?

stock oil pump = extra trunk space and less hassle so i really want this to work but don't fully understand it.

Some OKO carbs have a (single) oil injection port.

Most OKO carbs DO NOT.
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
mmeadows
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Re: Looking for 70cc polini big bore advice

Post by mmeadows »

Trafficjamz wrote:ome OKO carbs have a (single) oil injection port.

Most OKO carbs DO NOT.
well what about this "tapped second port" you ask scottinscotty about. can you explain it to me more. ive pmed scottinscotty but i dont think i'm worth his time :( which is understandable as i would be busy riding too if i had his set up :coolcruise:
84 Aero af05e Ruckus variator, rear metro wheel, Leovince pipe ( work in process... porting , nh80 reeds intake carb)
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Trafficjamz
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Re: Looking for 70cc polini big bore advice

Post by Trafficjamz »

the CT manifold had one hole tapped into it.

It is used to connect a vacuum line to the fuel petcock.

The stock manifold has two holes, one for vacuum and one for oil injection.
new best 1/8th mile time 9.647 seconds @67.155 mph 310lbs total weight
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scottinscotty
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Re: Looking for 70cc polini big bore advice

Post by scottinscotty »

well i have been on vacation.. when i get back home i'll take some photo's of the intake mod.. it's very simple.. if your running an oil injection pump "if you don't have a port in your carb" you'll need to tap a second hole and screw in a second fitting.. like i said when i get back i'll take a couple pics and post them... :geekdance:
72cc polini contesa kit
oko variator with 8.5 gram malossi weights
21mm Black Oko Carb & Ct Manifold
8.44 gear
malossi MHR exhaust
Dio zx trans conversion
1000 center spring
1500 grabbers
sef ramp plate
B9hs plug
GPS 60mph
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scottinscotty
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Re: Looking for 70cc polini big bore advice

Post by scottinscotty »

If you richen the pre-mix ratio (20:1 as opposed to 30:1) there is more oil and less fuel in the same volume of liquid, which effectively leans the air-fuel ratio. And this fact gives the clever tuner one more tool to use when the correct jet is not available or when none of the standard jets are exactly right. You can richen the jetting by slightly reducing the pre-mix ratio (less oil). You can lean the jetting by increasing the pre-mix ratio (more oil). The best part is that changes in the pre-mix ratio affect the jetting over the entire throttle-opening range, but the changes in ratio must be small to prevent excess wear from lack of lubricating oil or fouled plugs from too much oil.
72cc polini contesa kit
oko variator with 8.5 gram malossi weights
21mm Black Oko Carb & Ct Manifold
8.44 gear
malossi MHR exhaust
Dio zx trans conversion
1000 center spring
1500 grabbers
sef ramp plate
B9hs plug
GPS 60mph
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scottinscotty
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Re: Looking for 70cc polini big bore advice

Post by scottinscotty »

so when your mixing 32:1 your gonna go up on jet size... or if your running 50:1 your going down on jet size to compensate for the lack of or excess of fuel..
72cc polini contesa kit
oko variator with 8.5 gram malossi weights
21mm Black Oko Carb & Ct Manifold
8.44 gear
malossi MHR exhaust
Dio zx trans conversion
1000 center spring
1500 grabbers
sef ramp plate
B9hs plug
GPS 60mph
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