I dismantled the dead etek, which isn't too hard, but it does help if you
have a press.
It had totally shed about a dozen connections and some of these had gone
AWOL on the trip home. I've made new ones and re-soldered nearly all the
connections, but I have to fix my 1960's 'instant heat' iron to do the last
few. The motor won't be 100% but I'm sure it will be useful for something.
The motor that Trevor Lees of Lemco donated had the larger 7/8" shaft, so I
needed to either bore the pulley, or replace it. Taking no chances I changed
the gearing and bought a couple of taperlock HTD pulleys. The original
primary drive was 1:1 (30 tooth:30 tooth) combined with a 17:70 (4.11:1)
chain final drive. Going to a 24:36 (1.5:1) primary gives me about 6:1
overall and lowers the top speed to approx 40mph. I may bump the battery to
72 volt later to get the top end back.
Having swapped the brush gear over and installed the new motor I took it for
a test ride.
The performance was dissapointing to say the least. It was actually slower
accelerating than before. I checked the controller settings and then fearing
that the controller might have been damaged when the original motor let go,
I put a current clamp on the motor loop. That showed a health peak of 350
Amp, so I then dropped the belt off the motor and ran it from a single 12
volt battery. My hand held tach showed the motor spinning at 1400 rpm on a
shade under 12 volt (poor jump leads!), which is well over 100 rpm per volt,
rather than the 72 rpm/volt expected.
Having talked to Trevor, it appears that there were two armatures, a 127
strip (which is the normal one) and a 126 strip which is nearly twice the
rpm/volt and hald the power and intended for applications like 24 volt floor
sweepers. He thought he'd given me the motor he'd taken off the Drift
(upgraded to Lemco 200), but in any case is sending me another.
Once that's fitted I can put the bike on the insurance policy and take it
for an MOT. I'm not going to make the London to Brighton run and a 40 mph
top speed isn't going to impress many people around the Anglsea race
circuit, but it will be good to have another EV since I sold my Scirocco.
Paul Compton
www.evguru.co.uk
www.sciroccoev.co.uk
www.bvs.org.uk
www.morini-mania.co.uk
www.compton.vispa.com/the_named
