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Discussion Starter · #1 ·
well im new here and im builing a mini chopper and some was asking for pics so i figer i post my project

what i started with


a few days after i started i pulled the grinder and welder out and started cuting on the frame streched the lower 5 inches and raked the forks out and added a 20inch spoke wheel


then i picked up a x2 pocket bike to cut up for the motor and motor mount rear wheel dont worry the x2 will be rebuit but bigger and better :)
 

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Discussion Starter · #2 ·
built the exhaust



had some old rissers off my sportster so i cut them down and used them





built a set of baby ape bars for it and made a seat pan out of 10gauge sheet steel





chaged my mind on rear fender went with this one that came with the frame but it was broke in 1/2 and had 3 pc missing u can see some of my patch work i plastic welded in

 

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Discussion Starter · #3 ·
sanded the tank cover down



rear fender in its 3rd colt of primmer





and the first colt of paint this is the base colt finsh colt will have some art work and stuff done

inside pic



out side pic

 

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Looking really good man......Theres a member named mikeldoroba,,,if you could do a few shots and sizes of your frame hed be appreciative as hes looking to fabricate a similar design ,,,,,,,,,,,,

Theres ways to triple the power output of that engine and CVT transmission if your interested...Just say so and grab your dremel and a notepad....

Keep up the great work and the updates...........:thumbsup:
 

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Discussion Starter · #6 ·
More power how plz how lol

And yes when I pull the frame apart to paint it ill get specs of it this frame will be for sale soon as I'm going to build a full custom frame
 

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To get more power you need to pop the head and open up the bottomend,,

massage the ports,,ie: transfer ports,,intake port and exhaust port

add releif windows in the piston sides,,

reshape the piston sideskirt,,

deepen ring channel 1/32" and widen ring channel 1/64"

index the piston

deburr and smooth sharp edges from the piston edges

polish the piston,,pin bearing and pin aswell as rod journal

polish the cylinder

blueprint the fuel flow transition from the lowend to the topend to deliver maximum velocity by cutting off the corners from the cylinder skirt on flow side

take lowercase and port the flow side to run into the transfer port channels fast and smooth

reinstall the head without a basegasket to bump compression,,yamabond works great here...I use JB Weld...

lighten the flywheel

add a rocket key

mod and lighten the clutch

port the intake to match the newly ported intake

add a boost bottle setup

rebuild the carb with a real walbro rebuild kit..$10 bux on ebay shipped..

add a v-stack and hp airfilter,,,a detergent cap and pantyhose does a better job...........To choke the engine you just palm the opening shut and pull a few times the engine fires right up if tuned good..

There are a couple other mods you can do to make serious power

chop the cylinder top and turn it into a 2pc cylinder

do the full circle crank mod.......

add an expansion chamber to that exhaust pipe...

Then theres modding the CVT transmission by lightening the rollers so the variation becomes delayed enough to enhance bottomend takeoff immenseley....I reduced the total weights from 25.7 grams down to 20.8 grams...That reduction gave me a ton of takeoff......

Heres a thread to follow..same engine and its kind of guided by me..Im just giving pointers,,,hes doing the work....It adds depth to this post and should clear up most questions that I know are building...

http://www.pocketbikeplanet.com/showthread.php?t=79566
 

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Looks really good man! Nice paint job and good work on frame doooood!! Almost looks heavy tho.. Might need to find a 110 for that baby?! But then again follow Cams lead and thing will scream.. My bubbies X1 with the same engine goes about 40-45.. He did add a reed kit..

Cheers!
 

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Discussion Starter · #10 ·
i got a filter and v stack choke housing sofar was looking at a big bore kit
the frame is about 1.5 lbs more now and the gun amno box is 5 lbs it will run 30 mph righ now would like to get 60 or so out of it
 

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60 mph with a 49cc engine is asking alot, maybe a bigger engine? You could put two engines inline in that frame, CAM2 has done it in a mini bike frame.
 

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i got a filter and v stack choke housing sofar was looking at a big bore kit
the frame is about 1.5 lbs more now and the gun amno box is 5 lbs it will run 30 mph righ now would like to get 60 or so out of it

I only get 50 out of this one at the moment...its getting a new power attitude to make it hit 60............

 

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were would be the best place to get a big bore kit i want the max power i can get looking for a race ported head
The only place to get a 2pc headkit is PBU and theyre pretty expensive...The other way to get the power is Boosted306 [sam]...PM EPR hes got the direct e-mail for Sam...

The expensive PBU kit doesnt have full circle cranks ,, race ported lowerend or reshaped skirt to enhance velocity and flow....

In fact youll never find a full circle crank for a piston ported engine but I happen to know that the cag engine fcc can fit with a lil modding and works really-really well......


Its up to you on how much money you want to throw at it but once you get into the racing engine realm you have alot more stringency as to tuning,,maintainance and such...racing engines dont last very long and must be constantly monitored to avoid premature catastrophic failures.......My bada$$ engined bikes only come out on certain occaisions to keep them around iin 1pc longer and apart less.......
 

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It's a no brainer, you can get a new 49cc ported to the max for $60 to your door and it comes w/ a new set of rings. Tell Boosted306, Sam your leaving the base gasket off. If your piston is no good get anew one a 44mm 49cc Cag non ported piston sam can probably help you there, and mod and polish it and your Boosted cylinder. On my scooter, I have a chopper Jet Pro pipe upsidedown and a boosted ported intake manifold and Walbro WT-813 pumper carb.
 

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Discussion Starter · #16 ·
well i picked up a 49cc motor from a guy in town has starter and cluch has a after market flywheel but not sure if ill use it as on of the fins is missing
i been reading up of people porting the lower block ports so i may do that to is it will be geting a full circel crank and big bore im going to do porting work my self if i can get some help on how far i can go safely
tore down took 5 mins lol got to love these little motors lol


shot clear on the plastics


 

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Nice......The rewards of building it yourself is well worth it when you twist the throttle and you feel the power you breathed into it............

Take the piston without rings and put it in the cylinder and mark where the pins are.......thats your guide on that side as to how wide you cant make that port...You want to go atleast an eighth shy...................

You mimic shape and width on the opposite port

On the exhaust side you dont touch the bottom but you raise the top the thickness of the basegasket plus a hair more...The shape should resemble a muffintop kind of........

Its not the same head but the exhaust port shape has the same idea/port shape...............The sides were widened 1/8" on each side and raised 1/8" aswell........



 

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Discussion Starter · #19 ·
First off thanks everyone for the great info

Well after it dryed I had the ich to see what they looked like sitting on the bike so here they are still has a lot of frame and fork work still so.they came rite back off

 
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