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Discussion Starter #1
I decided to take my engine apart to find out if I had the 43cc or the 49cc, turns out mine is the 43cc :(

So I am gonna buy a new piston, cylinder, etc....

I was wondering, should I go with a stock 49cc kit or an aftermarket one?
and what brands.

Please post a link if you can. Thanks.
 

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There arent very many performance headkits for the cateye except for PBU and theyre out there on prices.......

Id do every mod you can do to it,,,get a new 49cc headkit and mod the headkit for true performance....................The 43cc can be modded to perform just aswell as the 49cc bbk too

The head must be mounted with yamabond and without a basegasket to increase compression

The exhaust port must be raised the thickness of that lost gasket plus 1 thickness more to increase revs....the port must also be widened 1/8" on each side to enhance scavenging

The skirt on the intake side of the piston must be trimmed up 1/16 to 1/8" ...

The intake port hole feathered out and blended wider and the purgeport hole drilled to 1/8'

You should also index the piston dome in the exhaust port area where it becomes a speedbump at bdc..............

Mods are:

hp carb w/ velocity stack and 90 degree bend hp airfilter

Ported intake w/boost bottle nipple,,,

boost bottles

rocket key

NGK sparkplug

lightened flywheel

lightened and modded clutches

Rev pipe perf pipe
 

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Discussion Starter #3
Alright thanks, I'm not looking to race or anything, just wanted a better top speed. I only topped out at 22mph on a gps :(
 

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But who prays for Satan?
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Hey Cam how do advance/rocket keys where and how do you attach them?
pull the flywheel, install "rocket key" and install flywheel! job done, but dont put it in backwards or it will "Retard" the timing!

NaSa.
 

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It advances your magnets 10%, just like turning the distributor on your car 10% forward. Makes your spark plug fire alittle sooner, which is good at 10,000 RPMs. It fits in the slot on your crankshaft under the flywheel.
 

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Hey Cam how do advance/rocket keys where and how do you attach them?
They attach something like this.................They do what EPR states they do.......

On a Zenoah engine the rocket key will be set the opposite way.......Rocket keys get set with the offset towards the exhaust port.................

 
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