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Old 01-11-2013, 01:21 PM
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AdrianM
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Originally Posted by Pulse_
How much roll out do you have in 10.5 blinky?

I would like to start with about 62mm roll out but have no idea what gearing I could use to achieve this

It's getting much clearer for the body choice, the BA004 - Bomb R sounds like the perfect body for 10.5 blinky but I'm wondering if it's as smooth to drive compared to a BA005 or AMR12. A body that provides massive downforce can also loose it more violently in slower sections, no? Doesn't the downforce make the car less predictable?
61.5mm roll out can be achieved with a 41 pinion, 88 spur and 42mm rear tires.

The formula is:

Diameter x 3.14 (pi) = Circumference
42mm x 3.141 = 131.88mm

Spur gear size / Pinion size = Gear ratio
88/42=2.095
88/41=2.146

Circumference / Gear Ratio = Roll out
131.88/2.095=62.95mm
131.88/2.146=61.45mm

I run the Protoform AMR all the time. I run 13.5 Blinky or 13.5 Boosted (faster than 10.5 Blinky) depending on where I race.

I think bodies are only a really big deal in low power classes like 17.5 and 13.5 blinky. There you have to keep the car free from bogging as much as possible to maintain momentum so lower downforce bodies and synthetic tires help. If I ran 17.5 i'd run the black art R8C with Black F and Yellow R tires. This would work for 13.5 blinky on a very high traction track too.

In 13.5 Blinky or Boosted, 10.5 Blinky or Boosted and Mod you need more downforce to maintain traction in the corners at higher speeds and as you apply power exiting corners. High Rubber content tires (Magenta F/Pink R) help generate more traction to allow for the higher corner speeds and forward bite to put the power down. Efficiency is not an issue as the motors plenty of power and the batteries have plenty of run time.
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