Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[CliC]

An automatic transmission is different - at least it has gears.  But, single speed EV bikes are not going to get this acceleration for a number of years unless they add gears.  And a clutch and manual gear shift is the lightest and cheapest and most efficient way to add that.

Well, there's one other way -- lower the direct-drive gearing and up the motor voltage. I think racing EVs run higher pack voltages for this (and perhaps other) reasons. For street EVs, though, the battery tech is going to have to advance a bit to get good range AND increased voltage.

[manlytom]

The problem is how to have both good top speed and standing start torque.  The reason that the car guys can do it is because the have very high motor voltages which gives the motor top end RPM and then they have a better gear ratio for starting torque.

For electric motorcycles, you really need well over 100 volts to have something that does both well.  So far, most of them just haven't got there yet, but they will.

Above is from Neal in the Brammo thread. This sounds like the way to go to keep things simple and not bother with a gear box.

[flar]

An automatic transmission is different - at least it has gears.  But, single speed EV bikes are not going to get this acceleration for a number of years unless they add gears.  And a clutch and manual gear shift is the lightest and cheapest and most efficient way to add that.

Well, there's one other way -- lower the direct-drive gearing and up the motor voltage. I think racing EVs run higher pack voltages for this (and perhaps other) reasons. For street EVs, though, the battery tech is going to have to advance a bit to get good range AND increased voltage.

That option would run afoul of my "for a number of years" disclaimer (which is specifically why I had put that disclaimer in there), eh? 

I realize that we will eventually have other solutions, but the post that I was responding to was claiming that a clutch "[couldn't accelerate faster than] the controller could program it with the flip of a switch".  What programming is that?  On today's EV bike engines and today's battery technology?

[protomech]

What are you imagining that the controller would program?  You need gears to get this acceleration.  How is the controller going to program away the need for gears?

Maybe he's talking about an automated clutch transmission. Honda uses a similar system for some of their bikes.

Re: higher voltage street bikes, both the KTM e-freeride and the BRD Redshift SM / MX bikes use a significantly higher voltage. KTM is 300+ volts, can't find a spec for the BRD but it's also quite high. Neither of these bikes are shipping yet.

Not sure what the hold up is. Possibly some components are more expensive (charger, motor controller), the battery tech should be easy.

Eg Zero's current config ZF9 is 18s6p of 3.7v 20Ah cells, for a total of 66v 120Ah. That could easily be arranged as 108s1p for a total of 400v 20Ah, or 54s2p 200v 40Ah.

Car EVs typically operate at hundreds of volts, including hybrids. 2000 Honda Insight, 144v, 1998 NHW10 Toyota Prius 288v.

[dkw12002]

Another month and nothing from Brammo. Supposedly Brammo put some Empulses out there for review by the motorcycle magazines, but all I can find is old stuff from over 2 months ago announcing the release date. Has anybody heard anything? It sounds pretty good on paper 0-60 in 5+ sec. 100+ mph, 115 mi range...everything but the price, that is, but we should be getting reviews, marketing, and some dealers by now. 

[Brammofan]

Been hibernating?
Most of the Brammo news gets shared and discussed over on the Brammo Owners Forum - brammoforum.com - but pricing has been announced, as have dates for journalist reviews and the first production models to those on the waiting list. A couple of videos, too.

[dkw12002]

 I sense restlessness over at the Brammo owners forum. You would think after 2 years of waiting for the Empulse, they would be used to it by now. LOL
 This is the month it is all supposed to come together...models built and shipped.

It seems like progress comes in fits and starts perhaps as a tranche of financing is applied to the project...then nothing for some time. I wonder if they have enough money to get a critical mass of bikes out? Apparently they have a bunch of pre-orders. Still, if they are producing them now, you would think they would use this as an opportunity for some free exposure in the press. The tension mounts. Maybe they can get Pres. Obama to go to Ashland and sing the praises of small start-up companies and green energy with the first Empulse rolling off the assembly line in the background. Motorcycles are way sexier than solar panels anyway. Plus the Chinese aren't making anything even close to an Empulse...yet.
 

[Richard230]

I had pre-ordered an Empulse two years ago this July.  I was informed that I would be receiving an email 90 days before my bike would be delivered to my dealer for purchase. Upon receiving the message I was to visit my dealer and give them a $500 (or was it $1000?) deposit to secure the sale. I would then be able to purchase the bike after it arrived in 90 days.  I still have not received any messages from Brammo about when this might happen.  In the meantime..........I Zeroed out.

[Larry295]

This Brammo doesn't make any sense to me, for the following reasons:

-Why try to match the performance of a regular bike when the price of the technology still doesn't allow it (half the power for double the price of a similar gasoline bike)
-Why increase the complexity and therefore maintenance cost (Clutch, gearbox), when the whole purpose of electric bikes is cheap running cost and low maintenance.

Zero is not trying to compete with gas bikes. Instead they are pushing the strength of the technology they have:

-Less power, so make a bike that will excel in the city:  keep the bike small and nimble for easy maneuvering.
-The batteries are still expensive, so make the bike almost free to maintain (no clutch, gearbox, chain ect...)

I think Zero is pushing the strength that the electric technology offers. Brammo is trying to compete with gasoline bikes, and cannot win!

[Richard230]

I have similar thoughts. But then I am not Brammo and it is their money. So if they want to follow that path, I say good luck to them and I really hope it works out they way they wish. I just wish I had the opportunity to buy the original concept Empulse, with the 10 kWh battery and the direct drive system. I am sure I would have been very happy with that bike.

[flar]

I agree that it is a striking tradeoff, but I need more range than anything that Zero has put out yet and the Empulse seems to provide that on paper.  For me, it is the right formula.

High up on my want, but not need, list is to have a high performing electric bike and the Empulse will perform much better than the other production e-bikes that have no transmission.  I test rode an S and it was adequate, but not exhilarating.  If it had the range, I might have bought it spurred on by my emerging green side.  For these prices, though, I would really prefer to be exhilarated.  I'd like to think of it as the "Tesla of motorcycles", but I don't think they reached quite that far.  Still, they've gotten a lot closer than anything else available, but at a premium.  If I can stretch it, I'll pay a bit of a premium to advance the state of the art to add "excitement" to the formula.

Also, the built-in quick charger is a big boon in terms of meeting my range needs.  Without it, I would use most of the range of the bike (and uncomfortably right at the max range of other production bikes) just to do my commute and then I'd really need to wait for the bike to fully charge before I could commute home.  Some commute days I'm only commuting for half a day so on-board quick charging is icing on the cake - it eliminates the last of my range issues without having to invest in extra parts and find ways to lug them around.

Now, could a much cheaper bike have met those critical range needs? - maybe, or probably.  Do I feel the added performance is unnecessary? - No, I very much would love to have it and think it is one of the advantages of electric vehicles - performance with economy.  Would I have enjoyed simpler maintenance - yes.

I'd love to see e-bikes in 2-3 years time when they can up the voltage levels to a point where they can have superbike performance, simple 1-moving-part drivetrains, plenty of range, and all of the economy they currently enjoy (as long as you resist the wrist).  Until then, the Empulse is probably the only formula that could deliver what I need this year plus some of my wants and desires - at a price...

[dkw12002]

But the big Empulse is 470 lbs. vs. 341 lbs. for the big Zero S. I don't see it outperforming the Zero S for range unless they have an eco or rain button you can push. Good speed and acceleration...but if you use it, the range will be very short...maybe 30 miles. 

[trikester]

As far as waiting for an e-bike to go into production, I'd like to remind everyone that from the time I put my $500 deposit down for a ZERO DS it was two years and one week to the day, when I received delivery on a 2010 DS. At the time I made the deposit, I had no idea that the DS would be the last model to be designed and produced. Things are a lot different now at ZERO and probably will be at Brammo when they get up to speed.

BTW - Zero nicely comped me ($0) the Corbin low profile seat as a reward for my 2+ year wait. At that time they were getting $500 for that option! I now have that same seat on my 2012 DS ZF6.

Trikester

[protomech]

30 miles? You'd need to push 300 Wh/mile for that.. I don't think even 100 mph will drain the battery that quickly.

At high speed the Zero seems to suffer from poor aerodynamics and possibly being pushed into a less efficient regime for the motor. At least the MIC steady 70 mph test is notably higher consumption (180 Wh/mile Zero vs 165 Wh/mile Brammo Empulse).

At low speeds the Empulse does use more energy per mile, but the larger pack mostly makes it a wash. At 45-55 mph the Empulse has about 20% more range, at 70 mph about 30% more range.

Looking at it another way, for a given range the Empulse can travel 10 mph faster. 80 miles on the Zero S ZF9 is about 45 mph, the Empulse should get 80 miles of range at 55 mph. 60 miles on the Zero S is about 55 mph, the Empulse should get 60 miles at 65 mph.

At least, that's what the specs indicate. We'll see what the real world range looks like.

[flar]

But the big Empulse is 470 lbs. vs. 341 lbs. for the big Zero S. I don't see it outperforming the Zero S for range unless they have an eco or rain button you can push. Good speed and acceleration...but if you use it, the range will be very short...maybe 30 miles. 

I'm just going by what they both claim and Brammo is claiming longer ranges for any given category.  I do note that the Zero web site claims EPA/UDDS test results whereas the Brammo site claims SAE results, but I believe that they are essentially the same standard - does anyone know any details on that?

In the end, it would be nice to see real world results from actual riders to see how they really compare.  I've driven cars that habitually always did better than their EPA ratings and cars that never got as high as their EPA ratings so there is some amount of variability in how machines respond to the tests and how they respond to drivers (or, at least, to me).