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yup just put it on a tripod or something and do some speed runs then upload to youtube and past the link here
 

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Discussion Starter · #43 ·
So if i get a shot of like have a spot visably marked and say 15 twenty feet have another marked u can find my speed? Or does it need to be that far? How far does it need to be?
 

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it dosent need to be marked off or anything scientific i can do it all in the video editing software
 

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And its not a stock a stock cag engine. It what a beleive is a 47cc. With a big bore. I drilled a hole in the intake and tapd for bb and ported out j7st the intake and gasket. Made it a real smooth transition to the boost bottle with it pointed toward the motor as much as i could. Got 7 tooth front and havent counted but think it was 52 or 54 in rear. No take off but pulls hard after about 20.

Only way I can see a small tool engine belt out those type speeds on that gearing and getting enough uumph to get those type of revs is it being built with an aggressive porting job and an ultra tight squishband hopped-up and tuned to run on either 100 octane 105 octane or even alky/methanol fuel mix then having an exhaust pipe that's specifically built for the port duration in the degrees that was grinded into the ports and deciphered using a degree wheel...


In order to decipher the fuel requirement you first need to get a squish calculation then a compression test with a pressure number to coincide with the squish..


Then you need to figure the type and size of the carb needed to feed the need.


Its really easy to prove an accurate GPS test to see if the pocketbike run is 100% accurate plus prove the run is 100% legit..


First cue up the GPS program and do a taped run in a car going 30mph for about a mile to gauge accuracy against the speedometer in the car.


Then take same camera put it on a milk crate and show the GPS screen on the camera and completely Zero it out on camera then strap the gps on the bike take a blast up and down the block then stop the bike in front of the camera get off and instantly show the camera the speed.


The fastest one of my cags went was 47mph on a 7/49 gearing with a 5 port 44mm bore engine with modified 19mm Del Rep carb.The test pilot was my 160lb lil brother..


My Polini 910 Carena 4.2 runs out at 51mph on 8/56 gearing same rider...

Got any pics of your mods?

Care to share your port sizes , degree numbers and the final squish and compression ratio of your build??

the twin enginned mini Harley in this picture had twin 43cc engines that were modified to roughly 4.25hp each..Top speed 50mph...…It was geared 17/33 on he drive side which works out to 4.16:1 ratio with the 3:1 reduction box transmission.


 

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Discussion Starter · #49 ·
Dont no all that ive did a couple small things that m8ght help it. But as far as inside the motor idk. Only thing ive done there is a cc reed. But we will see ill get a vid later today. I know its avcurate cuz i have been using it n the car too just to see. Ill send a vid later.. all i have is my phone to revord anything and that where my gps is. So if you can tell from a stand still video thats what ill get today. I know for a fact its doing over 40. Road beside my brother in laws 4 wheeler he toped out at 38 and i walked right around him.
 

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Discussion Starter · #51 ·
I know its got ungodly amoumts of compression all these vids where u see k9ds pull starting it standing beside there bikes. Woupd never happen. U would snatch the bike straight n the air.. ive done it. U have to have it planted with ur foot on the peg to even beggin to pull it. Thought the motor was locked when i first put it on and tried to pull it..
 

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Discussion Starter · #52 ·
And i would get him to video it but hes traded his 400 for a 700 this weekend and its got way too aggresive tires to go that fast on the street. And the mf sounds lile a pick up truck so riding it around here isnt a good idea anyway. He got the police called the first night he got it.
 

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Discussion Starter · #53 ·
But i can prob figure out a way to get a vid like that 2.. u want 1 continues video? Gunna be lile a 10 15 min video lol
 

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Discussion Starter · #54 ·
And so what will the conclusion be when all of u see im not lieing about it? Just a factory reject with good porting? Lol. I was gunna go back and port it eventually. Only reason i havent is i dont know **** about 2 strokes.. besides what ive read and researched. And btw it has no prob getting the rpms even geared lile it is.. gotta be easy on her takin off. Chain rattles good. But once u hit bout 15 or 20 u feel it straightin out and act right then u can get on her. As far as how many rpm idk. But shes a screamer
 

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Discussion Starter · #55 ·
Little cheap 20 dollar pipe from ebay. Oversized spark plug. Idk what its supposed to go in but the head that plugs to the wire is real small. So it just sits on there. Havent figured a way out to hook it tight without squeezing the boot closed on it. And i dont wanna do that. Added a boost bottle. Ported the intake out real good. But thats it. Been rid8ng it a long time. First with the 4 stroke 40. Then i cut and welded the motor mount to fit the big bore 49.
 

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Discussion Starter · #56 ·
Finally got the motor straight this time around. Last year it hit 39. But the motor was slightly off. Getting the chain and extra bearing on the front sprocket hot as hell. Gotta all that atraight now everythinh stays cool and runs alot smoother
 

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Discussion Starter · #57 ·
Ok so the way im thinking with the gps is. Ill vid the gps right beside the odometer. Then get out the car. Still gotta figure out how but strap the camera to me somehow because the straight aways are away from my house so u wouldnt be able to see me do it if i dont. Ride out get it to top speed and show the gps after... of course showing it every step of the way.. prob is i dont have a camera so ima have to do it with 2 phones. And idk how ima strap the camera phone to my bike. I guess zip tie the sob and ho0e it dont hit the ground lol. As for the fly by vid. Ill do that later today 8f it dont rain
 

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Discussion Starter · #58 ·
Didnt start the convo out to prove my speed lol but yall got me intrested now. Cuz im guessing its not supposed to be go8ng that fast.. wonder if my carb is sucking so much gas its leaning out at full throttle and screaming in rpms? Dont have the balls to hand over and look at the filter to see at full throttle. Hevk i d9nt even have the balls to pull full throttle until i gulp down 2 shots real qu8k lmao
 

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Discussion Starter · #59 ·
But back to my orignal question. Got my lighter flywheel in today. But ima drill it and grind on it sum to get it cleaned up and even lighter. Questiin is should i put the timing key in while im there or leave it alone?
 
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