FDR and rollout ratio
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I have been having issues with my esc heating up. my motor stays cool. i have messed with my pinion and spur, but im at 22/90 and i think 12/96 is as low as i can go. how does the fdr work out? i have read that you should get as close to 1:1 ratio for wheel:motor turn. so 1 turn of the motor should equal 1 turn of the wheel.
So heres the math i have found
to get the fdr: spur/pinion x trans ratio x diff ratio= fdr
so my wheely king has 22/90=4.091
trans is 15/28=1.86
DIff is 13/38=2.92
FDR=22.22(rounded up to nearest 100th)
for the rollout: tire size x pi(3.14159....)
My tires are 5" so multiply by pie= 15.707963 for the Rollout
FDR-Rollout should= as close to 0 as poss.( or between +1 and -1 aka 'sweet spot') if not then adjust tire, spur or pinion to get the ratio right
So..hope your still with me...
22.22-15.707963=6.492037so gearing up would bring it closer to 0, but gearing up creates more resistance=more heat. i know its a lot, but i hope somebody knows what im talking about and can see my errors.
I have alsoread that fdr is just spur/pinion x diff or trans ratio x diff ratio, which would make the final numbers different, obviously.
any insight on this. does it seemright?
might just be the esc, but i was hoping to figure this out before i dump another 100+ bucks into a new esc.
So heres the math i have found
to get the fdr: spur/pinion x trans ratio x diff ratio= fdr
so my wheely king has 22/90=4.091
trans is 15/28=1.86
DIff is 13/38=2.92
FDR=22.22(rounded up to nearest 100th)
for the rollout: tire size x pi(3.14159....)
My tires are 5" so multiply by pie= 15.707963 for the Rollout
FDR-Rollout should= as close to 0 as poss.( or between +1 and -1 aka 'sweet spot') if not then adjust tire, spur or pinion to get the ratio right
So..hope your still with me...
22.22-15.707963=6.492037so gearing up would bring it closer to 0, but gearing up creates more resistance=more heat. i know its a lot, but i hope somebody knows what im talking about and can see my errors.
I have alsoread that fdr is just spur/pinion x diff or trans ratio x diff ratio, which would make the final numbers different, obviously.
any insight on this. does it seemright?
might just be the esc, but i was hoping to figure this out before i dump another 100+ bucks into a new esc.
#3
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new CC sidewinder sct 3800 setup with 2s turnigy 5000mah 30c lipos. maybe should have went with lower kv motor and the MMP, but this was cheaper, and thats what i get.lol. i have talked to a dozen people and CC. CC told me to send it back. everyone else had diff answers, but seemed that the gearing might b the issue. i played with it but with no change. maybe just a lemon for an esc. it does happen. or maybe he gearing is way off. thought i would try everything b4 sending it back.