CB-72V

The List

Bill of Materials
Price(USD)
Weight (lbs)
Bike
CB750
0
200
weight guess
Motor
Perm 132
895
25
Controller
Alltrax 7245
590
5
weight guess
Batteries
UB121100
804
426
Throttle
Magura
50
Contactor
Albright
80
Fuse & Holder
20
Cable
what guage
45
Lugs
0
included in cable price
BMS
BattEQ
200
Charger
250
Rear Sprocket
72
40
wag
Front Sprocket
10
10
wag
Chain
20
wag
Motor Mount
100
wag
Battery Mount
100
wag
Data Acq & Battery Monitoring System
Pak Trakr
0
already got it
TOTAL
3204
656
YOUCH!
Tools & General Consumables
Crimp Tool
31.5
Cable Shears
26.25
Heat Gun
50
Heat shrink cable wrap
20
0

Core Components

1 kW =
1.34102209
HP
Motor
Batteries
Controller
Perm 132
???
Alltrax 7245
System Voltage
72
V
Max Voltage
72
V
Constant Current
110
A
Plan is for high Ah AGMs.
Max Current
450
A
Efficiency
0.91
Cost
590
USD
Constant Power
7207
W
Weight
?
10
lbs
Constant HP
9.7
HP
Peak Power (10 minute rate)
25000
W
Peak HP
33.5
HP
Peak Current
382
A
Cost
895
USD
Weight
25
lbs
Speed @ 110A
3000
RPM
Alternative Max Current
Alternative Lithium Batteris (I wish!)
300
A
Thundersky LiFePO4
21600
W
Nominal Voltage
3
V
29.0
HP
Capacity
40
Ah
Cells Required
24
Alternative Target HP
Cost per cell
80
USD
19
HP
Weight per cell
3.3
lbs
14168
W
Cost
1920
USD
197
A
Weight
79.2
lbs
BMS?
for now assume that YESA 
Charger?
system would be same cost
but include BMS and Charger

Batteries

   
Nominal
Nominal
Max Discharge
Cycle Life
Dimension
Weight
Weight
Voltage 
capacity  
Current 
(80%DOD) 
(mm) 
(Kg) 
(lbs)
US$
voltage
48
60
72
@ 0.3C 
(Continuous) 
# cells
16
20
24
weight in lbs for above system voltages
TS-LFP40AHA 
3.2V 
40AH 
120A 
1000
190x116x46 
1.5
3.3
100
52.8
66
79.2
TS-LFP60AHA 
3.2V 
60AH 
180A 
1000
215x115x61 
2.5
5.5
88
110
132
TS-LFP90AHA 
3.2V 
90AH 
270A 
1000
220x145x68 
3
6.6
105.6
132
158.4
TS-LFP160AHA 
3.2V 
160AH 
480A 
1000
285x182x71 
5.6
12.32
197.12
246.4
295.68
TS-LFP200AHA 
3.2V 
200AH 
600A 
1000
285x182x100 
7.6
16.72
267.52
334.4
401.28
TS-LFP400AHA 
3.2V 
400AH 
800A 
1000
452x288x71 
13
28.6
457.6
572
686.4
TS-LFP800AHA 
3.2V 
800AH 
800A 
1000
850x288x71 
25
55
880
1100
1320
UB121100
L
13
frame weight
200
W
6.75
ev motor and controller
30
H
10.5
batteries
426.6
Weight
71.1
6
426.6
bike weight
656.6
Price
134
804
rider weight
160
total weight
816.6
390
target speed
65
mph
91
wheel circumference
80
in
measured
Perm
ADC
wheel diameter
25.46
in
Weight
25
inches per mile
63360
in
RPM per V
45
revolutions per mile
792
RPM for 1mph
13.2
rpm
13.2
72
3240
RPM for target mph
858
rpm
1200
Amp @ target speed
110
A
wag
RPM @ target amp
2900
rpm
from Perm graph
3200
no load
Required gear ratio
3.38
2.67
original
Front sprocket
18
14
left column adjust front sprocket
18
original
Back sprocket
61
48
right column adjust rear sprocket
48
original
Bidwell range calcs
Volts
72
96
72
Ah
110
55
90
kWh
7.92
5.28
6.48
Range @ 30mph (kWh x 9.8)
77.616
51.744
63.504
Stop-and-go Range (kWh x 7)
55.44
36.96
45.36
110Ah
90Ah
55Ah
73
55
38.5
438
330
308

Kits

72 Volt Perm 132 Kit with Contactor
9.5 HP continous, 19 HP Peak (10 min)
Perm-132 motor 
48 to 72V 
$895
Magura Throttle 
  
$50
Alltrax 7234 
48-72V 300 amp 
$480
Fuse and Holder 
  
$19
Contactor 
  
$80
Wire and Lugs 
  
$45
  
  
 
Total 
$1,569
included in cable price

Misc

Names
CB 750 EV
CB EV 25K
CB EV 25K Li

calcs

Values from research (if you disagree, change them here - but you probably don't need to)
Symbol
Description
Value
Units
Source
Cr1
Rolling Resistance
0.015
from Brant
Cr2
Brake and Steering Resistance
0.003
from Brant
Cd
Coefficient of Drag
0.603
A
Frontal Area
6
sqft 
Crw
Relative wind factor
1.6
from Brant
Edt
Drive train efficiency
0.9
guesstimate
Values from bike (set them for your bike on the summary page)
Symbol
Description
Value
Units
Source
W1
Motorcycle Weight - w/o batteries (frame, wheels, motor, controller etc.)
230
lbs
guesstimate
W2
Battery weight
360
lbs
manufacturer spec sheet
W3
Rider Weight
160
lbs
bathroom scales!
Tc
Tire circumference
80
in
as measured
Environmental Factors (do you live in the windy city? adjust as needed on the summary page)
Symbol
Description
Value
Units
Source
w
Wind speed
5
mph
US average wind speed (according to Brant)
Constants (surely these are OK? Don't change them)
inches in a mile
63360
1 Nm in lb-ft
0.737
lb-ft
REQUIRED TORQUE
Calculated Values - Speed & Incline Independent (don't change these - change the values above)
rev per mile
wheel revolutions per mile
792
inches in a mile / Tc
Wt
total weight
750
W1 + W2 + W3
Tm
torque mutliplier
1.06
840.34 / rev per mile
Fr
Total rolling force
13.50
lbs
Wt * (Cr1 + Cr2)
Calculated Values - Speed & Incline Dependent (don't change these - change the values above)
Description
Level Ground
10
20
30
40
50
60
70
80
90
100
mph
Fd1
still air drag force
lbs
(CdAV^2)/391
0.93
3.70
8.33
14.81
23.13
33.31
45.34
59.22
74.95
92.53
Cw
relative wind factor (0.98*w/V)^2+0.63(w/V))Crw-0.4(w/V)
0.54
0.21
0.13
0.09
0.07
0.06
0.05
0.04
0.04
0.03
Fd2
relative wind drag force
lbs
CwFd1
0.50
0.78
1.07
1.35
1.63
1.91
2.19
2.47
2.75
3.04
Ft
Total force
lbs
Fd1 + Fd2 + Fr
14.93
17.99
22.89
29.65
38.26
48.72
61.03
75.19
91.20
109.07
Tl
Required torque on level
ft-lbs
Ft * Tm
15.84
19.08
24.29
31.46
40.60
51.70
64.76
79.78
96.77
115.72
5%
incline (approximately equivalent to 1mph/sec accel on level ground)
theta
arc tan % incline
0.0500
Sin theta
0.0499
Cos theta
0.9988
Fi
Incline Force
37.45
lbs
Wt * SinTheta
Fr
Rolling Drag Force
13.48
lbs
CrWCosTheta
Ft
Total Force
lbs
Fi+Fr+Fd1+Fd2
52.37
55.42
60.33
67.09
75.70
86.16
98.47
112.63
128.64
146.50
T05
Required torque at 5%
ft-lbs
55.56
58.81
64.01
71.18
80.32
91.42
104.48
119.50
136.49
155.45
10%
incline (approximately equivalent to 2mph/sec accel on level ground)
theta
arc tan % incline
0.0997
Sin theta
0.0995
Cos theta
0.9950
Fi
Incline Force
74.63
lbs
Wt * SinTheta
Fr
Rolling Drag Force
13.43
lbs
CrWCosTheta
Ft
Total Force
lbs
Fi+Fr+Fd1+Fd2
89.49
92.55
97.45
104.21
112.82
123.28
135.59
149.75
165.77
183.63
T10
Required torque at 10%
ft-lbs
94.95
98.20
103.40
110.57
119.71
130.81
143.87
158.89
175.88
194.84
15%
incline (approximately equivalent to 3mph/sec accel on level ground)
theta
arc tan % incline
0.1489
Sin theta
0.1483
Cos theta
0.9889
Fi
Incline Force
111.26
lbs
Wt * SinTheta
Fr
Rolling Drag Force
13.35
lbs
CrWCosTheta
Ft
Total Force
lbs
Fi+Fr+Fd1+Fd2
126.03
129.09
134.00
140.76
149.37
159.83
172.14
186.30
202.31
220.17
T15
Required torque at 15%
ft-lbs
133.73
136.97
142.18
149.35
158.48
169.58
182.64
197.67
214.66
233.61
20%
incline (approximately equivalent to 4mph/sec accel on level ground)
theta
arc tan % incline
0.1974
Sin theta
0.1961
Cos theta
0.9806
Fi
Incline Force
147.09
lbs
Wt * SinTheta
Fr
Rolling Drag Force
13.24
lbs
CrWCosTheta
Ft
Total Force
lbs
Fi+Fr+Fd1+Fd2
161.75
164.81
169.72
176.48
185.09
195.55
207.86
222.02
238.03
255.89
T20
Required torque at 20%
ft-lbs
171.63
174.87
180.08
187.25
196.38
207.48
220.54
235.57
252.56
271.51
25%
incline (approximately equivalent to 5mph/sec accel on level ground)
theta
arc tan % incline
0.2450
Sin theta
0.2425
Cos theta
0.9701
Fi
Incline Force
181.90
lbs
Wt * SinTheta
Fr
Rolling Drag Force
13.10
lbs
CrWCosTheta
Ft
Total Force
lbs
Fi+Fr+Fd1+Fd2
196.43
199.48
204.39
211.15
219.76
230.22
242.53
256.69
272.70
290.57
T25
Required torque at 25%
ft-lbs
208.42
211.66
216.87
224.04
233.17
244.27
257.33
272.36
289.35
308.30
Available Torque for Perm 132 @ 72V
Constants
1 Nm
0.737
lb-ft
Calculated from graph
WARNING: 
Assumes strictly linear relationship, working from a small low definition graph
Equation for straight line
y = mx + c
Data read from graph
20
110
200
A
3511
3480
3111
RPM
3.6
20.5
38.3
Nm
Calculated gradient and offset
mRPM
-2.22
gradient
cRPM
3466
offset
mTorque
0.18
gradient
cTorque
0.06
offset

summary

Motorcycle Weight w/o batteries
230
lbs
Original
El-Ninja
Proposed
Battery Weight
360
lbs
Ratio
1
Ratio
2
Ratio
3
Rider Weight
160
lbs
Front
Rear
Front
Rear
Front
Rear
Tire Circumference
80
in
18
48
16
72
13
48
Wind Speed
0
mph
Required Torque
0
10
20
30
40
50
60
70
80
90
100
Level 
15.84
19.08
24.29
31.46
40.60
51.70
64.76
79.78
96.77
115.72
5%
55.56
58.81
64.01
71.18
80.32
91.42
104.48
119.50
136.49
155.45
10%
94.95
98.20
103.40
110.57
119.71
130.81
143.87
158.89
175.88
194.84
15%
133.73
136.97
142.18
149.35
158.48
169.58
182.64
197.67
214.66
233.61
20%
171.63
174.87
180.08
187.25
196.38
207.48
220.54
235.57
252.56
271.51
25%
208.42
211.66
216.87
224.04
233.17
244.27
257.33
272.36
289.35
308.30
Available torque at the wheel for Perm 132 @ 72V
Original
El-Ninja
Proposed
Amps
RPM
lb-ft
Tw
Speed
Tw
Speed
Tw
Speed
25
3410
3.4
9.1
97
15.4
57
12.6
70
50
3355
6.8
18.1
95
30.6
56
25.1
69
75
3300
10.2
27.1
94
45.7
56
37.5
68
100
3244
13.5
36.1
92
60.9
55
50.0
67
Approx. top speed level ground
125
3188
16.9
45.1
91
76.1
54
62.4
65
150
3133
20.3
54.1
89
91.3
53
74.9
64
175
3078
23.7
63.1
87
106.5
52
87.4
63
200
3022
27.0
72.1
86
121.6
51
99.8
62
225
2966
30.4
81.1
84
136.8
50
112.3
61
250
2911
33.8
90.1
83
152.0
49
124.7
60
275
2856
37.2
99.1
81
167.2
48
137.2
59
300
2800
40.5
108.1
80
182.4
47
149.6
57
325
2744
43.9
117.1
78
197.5
46
162.1
56
350
2689
47.3
126.1
76
212.7
45
174.5
55
375
2634
50.6
135.0
75
227.9
44
187.0
54
400
2578
54.0
144.0
73
243.1
43
199.4
53
Available torque at the wheel for ADC MT2113 @ 72V
RPM
T
Original
El-Ninja
Proposed
50
0.25
Amps
RPM
lb-ft
Tw
Speed
Tw
Speed
Tw
Speed
112
7
25
5600
1.8
4.7
159
7.9
94
6.5
115
97
16
50
4850
4.0
10.7
138
18.0
82
14.8
100
86
29
75
4300
7.2
19.3
122
32.6
72
26.8
88
77
43
100
3850
10.8
28.7
109
48.4
65
39.7
79
71
56
125
3550
14.0
37.3
101
63.0
60
51.7
73
66
72
150
3300
18.0
48.0
94
81.0
56
66.5
68
61
89
175
3050
22.2
59.3
87
100.1
51
82.2
63
57
105
200
2850
26.2
70.0
81
118.1
48
96.9
58
54
123
225
2700
30.8
82.0
77
138.4
45
113.5
55
50
141
250
2500
35.2
94.0
71
158.6
42
130.2
51
47
159
275
2350
39.8
106.0
67
178.9
40
146.8
48
44
178
300
2200
44.5
118.7
62
200.2
37
164.3
45
42
192
325
2100
48.0
128.0
60
216.0
35
177.2
43