Simple Vehicle Power Calculator

Way too complicated for me... I build by the seat of my pants.... Yeah Yeah I know it shows.,,,

easier way... find a 1/4 mile streatch.. run it from a stop to full out down the 1/4 mile, time it with a stop watch.. weight the bike, then there are plenty of very accurate HP calculators online that use those 2 figures... that calculator I'm sure can be accurate, but if 1 number is off, those numbers will inflate immensly

matt167 said:

easier way... find a 1/4 mile streatch.. run it from a stop to full out down the 1/4 mile, time it with a stop watch.. weight the bike, then there are plenty of very accurate HP calculators online that use those 2 figures... that calculator I'm sure can be accurate, but if 1 number is off, those numbers will inflate immensly

Click to expand...

Weigh the bike AND yourself. Unless you bike is doing the 1/4 mile without you

Watts = E(VOLTAGE) X I(CURRENT IN AMPS)
a 900 WATT (PEAK) MOTOR RUNNING AT
24 volts should draw at least 37 amps under full load.
using something like heavy duty starter cable wire.
to avoid the voltage drop due to electrical resistance(R)
(I X R = E)
(E/R = I)
We used to figure the controller had to be good for double the max current load
for reliability, in the case of a 37 amp draw a Minimum 70 amp controller
would be a good idea.


.........................
Hi from the hills around Channel Islands University, near zip 93010
5 miles from the ocean

If any members have heard of the old "Pedal Power" US made electric bike kit sold in the late 1970's
and early 1980's ..It would be interesting to hear about what happened to make them dissappear.
-My current electric ride' was purchased from PP by me back in early 1980 - as a kit for $150.00
PP might have been located in New Jersey at the time.


Problems and Question

1) There are LOTS of very long steep hills
around here, the 1980 Pedal Power front friction drive wheel is essentially a 1" wide grinding wheel
mounted on the end of a 1HP permanent magnet motor with a spring loaded sissor' arrangement
to push the wheel against the tire and an old car florboard starter switch to make the
off/on battery connection

This thing EATS front tires on hills at the rate of 1 every 90 miles
-thats 4 tires in the last month an a half

2) The bike is currently running on a 12V (38 LB) group 22 nf gelcell
rated at 55 amp hours - capable of 19 miles at 16 MPH unassisted
-current draw up hills is around 60 amps for 10 min at a time (gets hot)
-tried a smaller U1 size gelcell ( have 5 of them from other projects)
but only went 9 miles and steep hill climbing speed was 3MPH less than the 22NF
..down from 9-10 to 6 mph
speed downhill behind the school reaches 41 MPH on the speedo (who cares )


Question: who sells a 26" bike tire hard enough / capable of
standing up to the slippage and grinding action ?

Regards,
New Member
Ron