Author Topic: what's the stock compression ratio  (Read 3633 times)

phatboy

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what's the stock compression ratio
« on: May 14, 2013, 11:37:15 PM »
Hey, can't seem to find this information, all pages say N/A

I want to install a BBK and would prefer keeping it close to stock compression to avoid burning pistons or having to use special high octane gas (best pump gas here is 91).

I see a few different kits available, one appears to have a flat top piston and stock head, says "raises" it to 9:1 compression. Like this one: http://enviromoto.ecrater.com/p/3369520/ncy-72cc-big-bore-kit-fo

So that means it's lower than 9:1?
Agility 50 w/72cc BBK, A9 cam, stock airbox and exhaust (both drilled out), remove air tube restriction, stock head, stock carb, 105 main jet, CDI cut, smooth variator boss, stock variator w/5g rollers

Vivo

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Re: what's the stock compression ratio
« Reply #1 on: May 15, 2013, 01:51:46 AM »
The Kymco website states the compression ratio of Agility 50 is 11:1

baddi

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Re: what's the stock compression ratio
« Reply #2 on: May 30, 2013, 11:19:24 AM »
It is a good idea to have a proper service manual. I recommend this: http://scootergrisen.dk/scooterhjemmeside/download/kymco_agility_servicemanual.pdf as it has alot of technical specifications. :D
First Kymco agility 50 (2008) 11.000+ km (dead)
Second kymco agility 50 (2010) 20.000+ km. Project Fuel Injection. Stolen.
Kymco K-pipe 125 (2014) 7400 km.

blue

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Re: what's the stock compression ratio
« Reply #3 on: June 02, 2013, 01:32:51 PM »
my manual says its 11. The last time I hooked a cage up to it it read 125 on the gauge which I know is realy good I have seen some as high as 130 thats the best you can do. If you go under 110
you are looking at rebuilding you motor.