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Old 03-28-2012, 12:45 PM   #79
JRWooden
Beastly Adventurer
 
Joined: Jul 2008
Location: The great state of confusion
Oddometer: 4,128
Quote:
Originally Posted by JoelWisman View Post
I'm telling you, BMW is running a test and substituting some regulators, at least that is what I suspect.

When I was with Volvo, we would go so far as to grind off part numbers on conspicuous parts we were substituting and stencil the normal part number back on, or pick a new part number out of thin air.

...

Then hacks like me build test beds and throw whatever we can think of at the parts....

Speaking of un-vetted...... I have modified two F800GS charging systems by inserting resistance between the stator and R/R. I ended up going with 0.09 ohms and saw peak charging power go down to 379 watts, idle charging power was not measurably affected. Stator temperature is the same at idle but down 9C at 4,000 RPM which is better then expected.

One rider is local and the other hales from AZ. Both riders are sworn to silence to maintain warranty i.e. this test is blind to even BMW lol.

Assuming these bikes don't explode in the next 2 months, or have the stators fail, I'll post how I made the changes and others can jump in on the experiment if they decide to.

All for now, back to testing batteries, wish me luck as the last battery I tested just released a cloud of hydrogen in my living room :)
Thanks Joel...

1) The part of this I was not focusing on was that the "new" R/R might be camouflaged ...
I had "assumed" we'd be able to tell them apart... sigh.........

2) Where can I get a job as a "hack"

3) If wire insulation follows the "norm" (10C change in temp. doubles/halfs the rate of reaction)
9C would almost double the life of our stator ... sign me up to loose 20W of output!
What wattage rating resistors did you use? I would think 10W would be more than adequate?

In other news, I have a conversation going with one of the guys from ElectroSport, I'll post it here once I confirm he does not mind that I do so - one of his ideas was to use a better grade of wire so that resistance would be less and thus I^2*R heating would be less as well ...
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