Different gear ratios for the 60 and 90s

[scottc]

I would like some info on all the different gear ratios that are available for the 60 and the 90 stingers helis,, Heck there is 3 different pinions sizes and 4 different main gears, how do these different ratios affect the flying of the 60 or 90 heli and dose it make any difference in the blade size as well. scott

[Gohbee]

Scott,

here are the recommended ratio's for the 90:

OS 91 use 11 tooth pinion and 91 tooth main gear

YS 91 use 11 tooth pinion and 93 tooth main gear

for OS70 use 10 tooth pinion and 95 tooth main gear

the 90 tooth main gear is more for folks that want to experiment around with the OS 91. However, because of physical constraints you will have to whip out the dremel to get everything to mesh with the 90 tooth main gear. We only recommend this for the advanced pilot/builder who likes to experiment.

I understand that the 12 tooth pinion is preferred by some FAI pilots. You FAI guys might want to chime in here.

-David

[scottc]

would i be under powered then if iam using the os 91 with the 93 tooth main gear, it seems a little undere powered to me for a 90 sized heli with the 90 engine. scott

[Gohbee]

what head spead are you running?

[scottc]

iam running around 1850
scott

[flyinfool]

What blades are you running?

[scottc]

I have a set of 700 rotor sports on the 90.