Just for info... Yamaha "Power-Assist" EAPC

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Location: Plymouth, England

Just for info... Yamaha "Power-Assist" EAPC

Postby ex925 » Mon Nov 16, 2009 12:30 pm

I was recently given a written-off Yamaha "Power-Assist" Electrically Assisted Pedal Cycle

Shimano Inter-4 hub-gears
c700 wheels and tyres
Front V-brake on rim, rear Shimano roller-cam hub-brake
24v. DC permanent-magnet 2-brush motor
Worm-drive in Bottom-Bracket
Pedal-pressure pulls drive-contact-switch arm inside "crank-case"
Drive-contact-switch was in turn linked to:- Solid-state controller
"Off/Economy/Power" switch on handlebar
Originally had detachable (8-amp?) Ni-Cad battery-pack

From my stock of junk.....

2 x UPS 12v/12a-h SLAs
Chinese 24v controller and twistgrip/throttle with backlit "on/off" switch
2x10-amp/240v.ac "on1-off-on2" dual-pole switches
Using both terminals of one for + feed and the other for - feed, giving:-
"On/Off/Charging" and 4x10amp contacts.......
AND: pedal or power or both driving..... (OR - gravity, of course)
(There is a very low-resistance free-wheel in the gear-hub)

So far 13.3 miles of 50/50 steep & level, and:
12-stone flabby-old-geezer-pedal-assistance to the poor little motor...
Has dropped the pack from 27.9v. to 25.9v. in an hour of riding
Motor never got more than pleasantly warm to touch,
Even at the top of "Heartbreak Hill", (1/4 mile, mostly 1 in 4, 10 miles on)
24.v 2amp Charger-light went back from red to green in under 4 hours

I know nil about "Fully-legal" EAPCs, (max. 200w, pedalling!, all that...!!)
This seems to have been a good machine to my view
Comments, anyone ?
All the best

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