No, thank YOU!
that's actually the first time in a while where we have all the needed information in a single post
Ratio dialed in for good speed.. 5:1
KartInfo by kartcalc.net:
Code:
[FONT="Verdana"]
[B][U]KART[/U][/B]
[INDENT][I]RW diameter[/I]: [B] 40.64 cm | 16 in[/B]
[I]Total weight[/I]: [B] 181 kg | 399.04 lbs[/B]
[/INDENT]
[B][U]ENGINE[/U][/B]
[INDENT][I]Original HP[/I]: [B] 9[/B]
[I]Asummed HP[/I]: [B] ~9[/B]
[I]Torque[/I]: [B] 17.8 Nm | 13.13 ft lbf[/B]
[I]RPM[/I]: [B] 3600[/B]
[/INDENT]
[B][U]TRANSMISSION[/U][/B]
[INDENT][I]Final ratio[/I]: [B] 5:1[/B]
[I]TC type[/I]: [B] series 40[/B]
[I]Lowest ratio[/I]: [B] 12.15:1[/B]
[I]Highest ratio[/I]: [B] 5:1[/B]
[/INDENT]
[B][U]PERFORMANCE[/U][/B]
[INDENT][I]Max Wheel Torque[/I]: [B] 216.27 Nm | 159.51 ft lbf[/B]
[I]Min Wheel Torque[/I]: [B] 89 Nm | 65.64 ft lbf[/B]
[I]Acceleration[/I]: [B] 3.57 m/s² | 11.71 ft/s²[/B]
[I]Top Speed[/I]: [B] 55.16 km/h | 34.27 mph[/B]
[/INDENT]
[/FONT]
(4.7:1 would be the absolute highest I'd recommend
)
but you asked for torque.. so here we are:
number from the guts... 7:1 ratio (mid everything)
KartInfo by kartcalc.net:
Code:
[FONT="Verdana"]
[B][U]KART & ENGINE [/U][/B]
[INDENT]as above [/INDENT]
[B][U]TRANSMISSION[/U][/B]
[INDENT][I]Final ratio[/I]: [B] 7:1[/B]
[I]TC type[/I]: [B] series 40[/B]
[I]Lowest ratio[/I]: [B] 17.01:1[/B]
[I]Highest ratio[/I]: [B] 7:1[/B]
[/INDENT]
[B][U]PERFORMANCE[/U][/B]
[INDENT][I]Max Wheel Torque[/I]: [B] 302.78 Nm | 223.32 ft lbf[/B]
[I]Min Wheel Torque[/I]: [B] 124.6 Nm | 91.9 ft lbf[/B]
[I]Acceleration[/I]: [B] 5 m/s² | 16.41 ft/s²[/B]
[I]Top Speed[/I]: [B] 39.4 km/h | 24.48 mph[/B]
[/INDENT]
[/FONT]
7:1 already gives you good torque and should be able to climb reasonable hills
(I will crosscheck to verify in a moment...)
you can however safely lower the ratio to 9:1
(enough clearance in most situations thanks to the wheelsize)
KartInfo by kartcalc.net:
Code:
[FONT="Verdana"]
[B][U]KART & ENGINE [/U][/B]
[INDENT]as above [/INDENT]
[B][U]TRANSMISSION[/U][/B]
[INDENT][I]Final ratio[/I]: [B] 9:1[/B]
[I]TC type[/I]: [B] series 40[/B]
[I]Lowest ratio[/I]: [B] 21.87:1[/B]
[I]Highest ratio[/I]: [B] 9:1[/B]
[/INDENT]
[B][U]PERFORMANCE[/U][/B]
[INDENT][I]Max Wheel Torque[/I]: [B] 389.29 Nm | 287.13 ft lbf[/B]
[I]Min Wheel Torque[/I]: [B] 160.2 Nm | 118.16 ft lbf[/B]
[I]Acceleration[/I]: [B] 6.43 m/s² | 21.1 ft/s²[/B]
[I]Top Speed[/I]: [B] 30.64 km/h | 19.04 mph[/B]
[/INDENT]
[/FONT]
That will come at a price of top speed as you can see, but that's massive torque to play with!
In the end that's up to you.. anything within 5 to 9 would work
[
EDIT]
So... UPHILL torque
Fi = m * g * sin(alpha) (inclinational force to overcome, with masss m, on an alpha inclination)
(I'll stick with metric units, that's just much nicer...)
181kg * 9.81m/s² * sin(10°) (ten degree angle is ~18% inclination..MASSIVE in short)
that's 308.3 N of force.. times wheel radius (0.2032 )
62,65 Nm needed to "not roll down" said massive inclination.
as you can see, all three ratios should be able to get up such hill with your engine.. without a problem
(just at very different speeds
)
'sid
