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[flar]

TESLA Quote:
"Sixty-nine cells are wired in parallel to create bricks. Ninety-nine bricks are connected in series to create sheets, and 11 sheets are inserted into the pack casing. In total, this creates a pack made up of 6,831 cells.

There's something wrong with the math there.  69*9*11 == 6831, so the 99 is actually factoring the factor of 11 in a second time.

(And, sure enough, I double checked on their web site and those are the (mismatched) numbers they quote.  I'll send off a note to their webmaster...)

[Lipo423]

I have not made the math, so, I guess you are right.
I would really question the fact that they fully disclose 100% their way of connecting the cells...I would not do that...they do not say how though 

[dkw12002]

Speaking of cooling off the cells, I have read the new Brammo Empulse will have liquid cooling. Is the liquid cooling for the motor or for the battery, or both? Next question is why does Zero NOT need liquid cooling? Will we see problems riding in the hot summer months? My 2011 S fan comes on with any hard riding, and stays on up to 5 min. after I stop, which makes me wonder how efficient the fan is at cooling off the motor. Far as I know there is no cooling for the battery pack. Whenever I feel the motor housing though, even after a hard ride, the motor feels only warm and never hot. Of course my Agni motor has air holes in it and the bike weighs under 300 lbs. which may be how they can get away without water cooling. Is the 2012 cooling going to be good enough for the bigger pack and motor at 105 degrees F?

[Richard230]

What has been reported about the Empulse is that it will have a liquid-cooled motor and battery pack. But that is just speculation and until Brammo finally introduces the production version of the bike, that is all we have - speculation and guesses.

My 2012 Zero has an internal motor fan that only works when the motor is spinning and the battery pack doesn't appear to have any cooling device. Hopefully, the components have been tested in the desert during the summer as they didn't get that kind of heat in Santa Cruz last year.  Around here, if we get up to 80 degrees we figure it global warming has occurred.   

I think the way Zero is handling the heat issue is with sensors and the controller. If any component gets too hot, the controller just dials back your fun to prevent melt-downs.

[Lipo423]

Yep, that's what I have been told, sensors for motor & battery...
I think they will have to look at this in the future, but at the moment range & reliability is on the table...whenever they will get to the real sports electric bike, it might be the time to look at more sophisticated cooling systems.

Richard, when I read your message about your experiences over 50 years you made me think...what a difficult time to get things up and running in the past...and now that we have everything, we complain...

[Richard230]

I tell you, Lipo423, when I first starting riding, I always carried a tool bag, spark plugs, cables and other parts and expected to use them. The problem was that I had no mechanical knowledge and the rider's manuals were written in Japanese pidgin-English. Plus, I had never even heard of a factory service manual. Fortunately, most of the mechanical things were easy to access and to figure out, but it was still irritating to have the vehicle stop every 50 miles or so and to sit by the side of the road to make repairs or adjustments.  Everything is so much better now.   

[dkw12002]

My experience with motorcycles and scooters is the same as with computers. If they run well at first, they will run well a long time. If they don't, often the problems never get sorted out and you are stuck with the quirks for the duration.  Glad to say my Zero has run superbly from day one. I do not plan to ride any bikes during the hot summer hours. Morning and evening rides only with 100 degree days. Hot weather is not so good for IC bikes either, especially idling in traffic. The other thing I do with all my bikes is run them every day at least a little. Almost all problem with bikes start out with the words, "I hadn't started my bike in a month or so when....." Stale gas in the carb plugging up the jets may be the no. 1 problem. At least we don't have to worry about that with the Zero.

Thunderstorms. I do unplug my Zero when thunder storms are predicted. What happens here is the electricity will be interupted a second or two, come back on, off again, back on several times. I can imagine that would not be good for the charger and BMS.

Brammo is an interesting Co. They started out as a car company and have a history of not bringing their concepts to market. The Empulse though has already been on the track racing. You can see YouTube videos of it. I don't think the Empulse of 2 years ago had the clutch and gears to shift as an option, but I think it had water-cooling. Their problems might be more along the lines of marketing and production costs rather than technical. They may need someone with deep pockets to help them out. Richard?

[Richard230]

Sorry, dkw12002, I already helped out Zero.   

Say, speaking of DKW's, my first car was a 1960 DKW Junior, with a 850 cc, 3-cylinder, two-stoke motor that was sold by Studebaker when they ran out of real cars to sell.

[Richard230]

I posted this link above in the "News" section, but in case you didn't see it, Motorcycle Daily has published the entire City Bike article here:

http://www.motorcycledaily.com/2012/03/md-quick-rides-2012-zero-s-and-brammo-enertia/

What is just as interesting as the article, are the many comments that follow it. It is clear that motorcycle enthusiasts are somewhat polarized about the benefits and future of electric motorcycles.