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[Richard230]

Apparently the Empulse has integral battery heaters that operate when the bike is charging.  I haven't heard if they also work when it is running.  The cooling system only serves to cool the motor (to my knowledge) and the question about the transmission oil is interesting.  All transmissions that I am familiar with are used on IC motorcycles, which tend to get pretty hot during normal operation, compared with the ambient air temperature.  The lube specified and the design of the transmission most likely takes that into consideration and is likely designed to function best when hot.  Most IC transmissions tend to shift hard and be kind of "clunky" when cold and oil-bath clutches can stick and operate slowly until their oil warms up, too. Hopefully, all of those factors were taken into consideration when the Empulse gear box and clutch were developed.

[Lipo423]

I do experience the same "lower range" problem, which is unfortunately normal -some of you may remember discussing this topic a few months ago in a different thread.

Cold weather is not a good friend of Lithium batteries (whatever the manufacturer states in the operating temperature specsheet), on top of it, when riding, because of the windchill effect temperature drop + (our batteries are enclosed in an ALU case, which is even worse in this application/riding environment) are far lower that in stationary mode. + the effect on the electronic control system going crazy -Zero has not build it with military grade components- be patience, the summer is around the corner   or do as Richard does

Take a look at the windchill chart below
http://www.ncdc.noaa.gov/oa/climate/conversion/windchill.html

Battery heaters? Mmmm...Lithium batteries do not like to be charged when hot, I guess this is for really low-ambience temperatures.

[NoiseBoy]

It would be interesting to calculate how much power a heater would draw to bring the cells up to optimum temperature and see if the benefit you would gain by doing so would actually exceed the power used by the heater.  I suspect its a close run thing in all but the coldests (i.e. electrolyte freezing point) temperatures.

It would make no sense to fit battery heaters as standard to a bike where the vast majority of riders have no intention of riding below freezing on a regular basis.  Don't forget that those of us on this forum are generally enthusiasts and so probably have unusual riding habits.

[protomech]

Take a look at how the Empulse modules are being built:
http://hellforleathermagazine.com/2013/01/fiscal-cliff-bill-extend-electric-motorcycle-tax-credit/



The Empulse and the Enertia Plus both have these cell heaters. Those can't be very expensive. I don't think it would make sense to heat the batteries with the cell heaters unless you were doing so from the grid, which the Brammo bikes will do. BrammoBrian says they reduce charge rate and begin heating the cells if they are below 10C / 50F, so it's possible their particular cells really do not like charging in the cold.

Nevertheless, seems like a good and inexpensive solution.

[trikester]

Ah, yes, more weight. Shall we start a pool on the when our electric bikes hit the 600 pound mark?

Trikester @like.emlight.now

[protomech]

Thin copper heating elements are probably not a major contributor to the Empulse's bulk OR cost.

I think you could build a 20-25 kWh touring bike at 600 pounds today. With some drag reduction it could give Tesla Model S type touring capabilities on a bike (ride for 2-3 hours, charge for 0.5 - 1 hour). Cost (and therefore volume) would be prohibitive.

[emotofreak]

"Thin copper heating elements are probably not a major contributor to the Empulse's bulk OR cost."

I disagree. Let's throw out some WAG numbers here. Let's assume those heaters are at least 1$ea. Let's assume they use 9 per module. 7 modules per bike (I think?), 63 total. Guess another $20 (at least, could be much more) in connectors wiring and such. That is $83 materials cost. Maybe another $20 labor for installation. Plus the hardware to control the thing. Plus the NRE of designing the hardware/software. I think you are looking at over $100 more like $200 to have battery heaters @ cost. By the time it gets marked up to the customer it is probably closer to $500. Don't get me wrong, it is an awesome feature for those that need it. It adds costs and complexity for those who don't. I bet if it was a $300-$500 option, the majority of purchasers would not opt for it.

[kingcharles]

I would buy it because I need it to be able to ride all year long. Although I wonder why they are so silent about it. This would be a nice feature against Zero (I assume they don't have heated cells).
Or would it only mean that their cells are lower grade than Zero's cells?

So my question: why is it not listed on the Brammo spec sheets?

[protomech]

Probably 8 per Empulse module, 7 modules per Empulse. Probably 11 per E+ module, 2 modules per Enertia Plus. They can mostly spread the expense of the hardware/software design effort across both the Empulse and the Enertia Plus, though I expect the up-front design effort is non-trivial. Marginal cost to

It sounds like the cell chemistry Brammo uses has a sufficiently restrictive storage/charge temperature that normal motorcycle usage would require cell heaters, where most Zero owners do not require cell heaters in daily operation. However, even if the bike is stored in cold conditions, below 20F the Zero BMS disables charging (or possibly higher?). If temps are below 20F and charging is disabled for a sufficiently long period - perhaps a week for pre-2012 bikes, perhaps a month or more for 2012 - then the bike battery could be damaged by over-discharge. Maybe the Zero BMS is smart enough to disconnect all drains when the battery SOC reaches a certain point as a battery preservation effort?

[manlytom]

1. heaters not on Brammo spec sheet => they might be needed for the Brammo battery tech than the Zeros

2. keep it simple, please. Zero has been thus far successful to keep the whole package simple, no heaters, no gears, no liquid cooling => the beauty is in a well working simple package !

[CliC]

I would buy it because I need it to be able to ride all year long. Although I wonder why they are so silent about it. This would be a nice feature against Zero (I assume they don't have heated cells).
Or would it only mean that their cells are lower grade than Zero's cells?

So my question: why is it not listed on the Brammo spec sheets?

It might be related to which Brammo's target market appears to be, the well-heeled IC sport bike rider who is intrigued by electric. They have to reduce the number of weaknesses the Empulse has relative to IC bikes, and downplay the ones they can't yet get around. Modern IC bikes don't generally have starting or refueling problems in cold weather, so Brammo perhaps simply made sure that the Empulse didn't, either. No need to call attention to it

[soup]

I Live in Arkansas. I have a ds9. I ride at 25 and up and the colder the slower I go. I have not rode below 25. My bike stays under a carport in the cold plugged up. If it gets colder than 20 I have outside a pump house that temperature does not get below 30 that I put it in. Last Thursday I rode to my brothers it was 35 it is 25 miles to his house I rode at 60 and 70 I had 6 bars when I got there. I plugged into outside plug was there 2hours. Rode 30miles back had 9bars to start home I had 3bars.

[protomech]

We've had warmer temperatures here recently. 40 and 50+ degrees. I haven't seen any of the inaccurate energy gauge behavior when the bike does a cold soak above 40F.

[Daveruns]

Flashing triangle this morning on my ride in to work flash.flash,pause,flash,flash,flash, pause, repeat. Went out and checked at noon, no more flashes. Talked to Zero about what was happening and they tell me it is a connection problem. I asked about the warmer noon time temp explaining why the problem went away. They asked me about charging and temp. Upshot is that you are not to charge the bike if it is below 20 degrees. This is in the manual. I missed it and have been leaving it in the garage charging when it is down to 10 degrees. Hard to ride in the winter when you can't charge overnight.... I may build a ramp to move the bike into the basement during the winter.

I wonder it this is common knowledge and I was just out of the loop? If not, we need to get the word out.

[BSDThw]

There was some talk about this problem, but in the Who's taken the coldest Zero ride? thread so not really easy to find and not really finished!

http://electricmotorcycleforum.com/boards/index.php?topic=2430.msg11123#msg11123