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Old 11-12-2008, 08:24 AM
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yyhayyim
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Originally Posted by Ramyuras
I don't think I am getting this gearing stuff, I am using 98 spur and 49-52 pinion with the 18t pully for rubber on carpet and reading on some of the post about gearing it seems as if I am undergear using 17.5 trinity motor the only problem I am having is if I go up to 52t pinion me lap time go's up and if I use the 49t pinion my time go's down and the lap time is more consistant but now I see most of the guys on this thread are geared much higher I am about 2sec off the fastest pace am I not getting something here about my gearing, my home track is about 90'x40-50 some where around there any suggestion.
Read thru this article: http://aedownloads.com/pdf/gear_ratios.pdf

pretty much all the basics of gearing is explained there and should be helpful to you

with 18T pulleys, your Cyclone's internal ratio is 2.166

So with a 98T Spur and 49T pinion, your Final drive ratio(FDR) is: 4.33
(98 divided by 49, multipled by 2.166 = 4.33)

98 Spur and 51T pinion, you get a 4.16 Final drive ratio(FDR)
(98/51 X 2.166= 4.16 )

This should be fine for the 90' track you're running on...try to gear it so that:

1) car reaches tops out top speed at around 90% of straightaway
2) doesnt over heat: keep motor ESC temps below 180F...you're topping out around the 90% mark and your motor's coming off the track in the 170+ deg range, then maybe you should go down a tooth or two on your pinion gear.
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