Gear ratios

[recracer]

Does anyone have a GY-5 lifanoid owners manual showing gear ratios ? My math is not working , but i have a replacement engine on my GY-2. the ratios from my manual ,more than likely primary ratio is different in my replacement engine .

[recracer]

i did some more searching and found a couple blogs stating ,the gy-5 200 has a ptimary reduction of 3.333 . my owners manual states primary reduction is 4.055 . 1st threw 5 gear all the same both bikes . So i believe i have the3.333 in my engine . calculates the mph where i thought it should be .

[Cal25]

Are you using one of those online calculators? Sure would be handy to determine a sprocket combo. I tried one but without the primary ratio you could not get the info.

[recracer]

Are you using one of those online calculators? Sure would be handy to determine a sprocket combo. I tried one but without the primary ratio you could not get the info. cal i added a formula in the megelli250r thread street bike section . you can check it out there and compare with the charts to see how i applied it .

[bigheavy150]

Im not sure if this is what your looking for but

Engine Model: Lifan 162FMJ
Type: 4-Stroke single-cylinder Over Head Cam air cooled
Bore & Stroke: 62.0 x 49.5mm
Compression ratio: 9.0 : 1
Displacement: 149.4cc
Max. HP: 13.5 HP @ 9,500 rpm
Max. Torque: 8.25 ftlbs @ 7,500 rpm
Idle: 1,500 RPM
Starter: Kick Start & Electric Start
Spark plug: NGK D8EA
Plug Gap: 28 or 0.6-0.8mm
Ignition system: CDI (Capacitive Discharge Ignition)
Lubrication: Pressure / Splash
Oil capacity: 8L (10w-30)
Measurements: 14" x 13" x 17.25"
Weight 63 Pounds
Clutch: Manual
Gears: 5 speed
Ratios: 2.769/1.882/1.400/1.130/0.960
Magneto: Permanent magnetic
Voltage: 12 Volt
Accessories Power: Lights and other accessories
GEAR RATIOS:
primary 4.055
1 2.769
2 1.882
3 1.400
4 1.130
5 0.960
final 3.14

[recracer]

bigheavy150 Thanks for posting that info . That is the same as my owners manual states for the viva/lifanoid 200cc engine . However in my case ,doing the math with the primary 4.055 ratio
to calculate mph . it's way off . since i have a replacement engine 3.333 quoted in a blog, seems to be correct . Your specs indicate that your 150cc has lower ratio (higher numerically) of 4.055 and a sprocket ratio of 3.14 , 4.055 x 3.14 = 12.732 overall . this can be used to multiply by each gear 1st ,2nd and so on ,to get the true reduction for each gear http://i440.photobucket.com/albums/qq127/recracer/Megelli%20250r/GearComparisonMegelli001.jpg[/img]