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Trained Chimp
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364 Posts
For another $20 you could have Sam build one. One that you know is good. That and you dont have to build it.
 

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Trained Chimp
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364 Posts
I already bought it I just need to know if I need to get it remachined
Its a little late to ask now isnt it? I havent bought a bb kit. But from what Ive read. Yes you will have to work some magic to get them to where their supposed be.

Im waiting for work to pick up then my motor goes to Sam.
 

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Trained Chimp
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364 Posts
Just a thought. Why dont you contact Sam and see if he could do it. Maybe he will work on a price for you since you already have the parts. He sounds like the guru. Lol
 

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Banned
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24,164 Posts
I does not have a full circle crank, its a 49cc, 12mm stock cag crank. For that price it should have a FC crank. Wish you would have asked.
It will work, but how well???
 

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GHETTO FABRICATOR
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1,114 Posts
I does not have a full circle crank, its a 49cc, 12mm stock cag crank. For that price it should have a FC crank. Wish you would have asked.
It will work, but how well???

Product description indicates a full circle crank. Picture doesn't have the crank but description says it has one.
 

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Registered
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30 Posts
Discussion Starter #9
Im new and im 13 I was wondering how can I tell between fc and stock and anyone wanna teach me I wanna know everythng
 

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Banned
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24,164 Posts
The sides of the crank are a round circle, they come in 10 & 12mm pin bearings, so you have to have a 10 or 12mm pin piston too match.
If they said it has a FC crank it probably does, but it is stupid to show a stock crank in the Ad. Just wait and see & will go from there.
You do do do a few mods to get more out of it, also don't know how much compression it has either, or Squish. You raise and widen the exhaust port, and open up the main intake ports, and you can leave the base gasket out for more compression.
Here is photos of one of my modded engine parts.
 

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Banned
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21,744 Posts
Any machine shop can mill it but you need to know how much to remove by doing a squish calculation.....

After a few mods to my Zenoah powered cag heres the numbers on a virgin build-up.....Im using a 15:1 dome with a thicker head gasket............The numbers will improve as the engine breaks in too................

 

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But who prays for Satan?
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6,571 Posts
did somebody say setting Squish? well, along with checking it, my little helper will show us how it's done REALLY soon (Maybe tomorrow?)

Here he is practicing for the tutorial!

:thumbsup::D:thumbsup: <---PBP home of the $1,000 animations, FOR FREE! <---Please join club pbp for $10 a year once I get it going again, most of the $$ will go right back in to PBP for contests and forum additions / support etc.. <---not one penny to me personally :p
 

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But who prays for Satan?
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6,571 Posts
Thanks Cam, We're gonna need a new section pretty soon here, I hope I don't Blow Up my computer with all the rendering in the summer time, I've got 37 minutes of battery backup just in case the power goes down! (Burn in heckfire Enron!)

haha, 1.21 gigawatts <---Gotta go Back In TIME....
 

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Banned
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24,164 Posts
I don't think you can bore it, They already bored it from 40mm to 44mm, if you take anymore out you could have heating problems, walls to thin.
Also they are cast alum, and I think they plate the cylinder surface after its machined.
Boring on engine that small adds very little size, stroking the crank, and a different piston pin location is the best way to a bigger eng.
A machinist will want $120 just to do start work, to much money fot this junk. Just get a bigger engine.
 

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Banned
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21,744 Posts
Well I got an engine builder who bores motors and I mean he should know not to take to much out
These engines dont need the extra spendature of an engine builder unless hes doing the labor of getting an initial squish setting number for free......

Hopefully today our faithful admin Nick will have that animated tutorial for calculating squish ready to view so you can do it yourself and gain valuable knowledge for this bike aswell as the next bike.............
 

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Ninja Racer
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2,767 Posts
so squish is the distance of head to cylinder?
looks like you use some plastic gauge like you would to check crank bearing clearance in a car engine
 

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But who prays for Satan?
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6,571 Posts
so squish is the distance of head to cylinder?
looks like you use some plastic gauge like you would to check crank bearing clearance in a car engine
Super close Blitz, was that single picture worth that many words?

basically if you look at the head "Dome" the wide flat portion can be called the "Squish Band" we stick some solder in there, bent at a 90 degree, and placed "Over the Piston Pin" inline with it <---to keep the piston from just tipping and giving you big old numbers, we get the solder in there, give it two nice slow 360 degree pulls, and measure the squished solder using some calipers.


and then do another piece of solder facing the other way, just to be sure, then there you have it, .5mm is really good, and usually gets you somewhere close to a 15:1 compression ratio. <---can do pump gas, but also loves up to 110 octane <--I think...
 
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