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Old 11-26-2007, 11:19 AM   #189 (permalink)
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
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Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 55.97 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 67.41 mpg (US)
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12-01-2006, 10:58 Pm

Originally Posted by SW
Hook 'em together and see which one wins.
Hoo ha! That's a good one

FYI - what happens if you run a motor backwards when the brushes are advanced against rotation in the "default" direction:

I installed my brand new 8" motor as it was shipped to me, and in the first 5 miles it burned the brushes and ruined the commutator. Turn out that unlike other cars on Hondas the motor shaft rotates CW, but default plate advance is made for CCW. No one mentioned that, and I always thought that DC motors are symmetric. Expensive mistake, exactly because of brush advancing. I'm sure I am not the only one discovered it hard way.
Source: ev archive
Most motors run CCW (facing the output shaft) by default (ie turning the tranny input shaft CW). But this guy put his motor on one of them "backwards" Honda trannys (CCW input shaft), and just reversed his field to make the motor spin the other way. Oops. His brushes were timed for the other direction. Must have been some good fireworks going on that of course he couldn't see.

I guess I'll be looking pretty carefully at this this weekend.
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
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has launched a forum for the efficient new Mitsubishi Mirage - fuel efficiency info for Geo Metro owners - electric car conversion on a beer budget
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