Comparing the Empulse with the 2013 Zero

[Richard230]

I just visited Terry Hershner's (offthegrid) Facebook page this morning to get updated on his adventures in the Bay Area (he seems to like it here) and I noticed that he mentions that he is likely the only person who has ridden both the Empulse R and the 2013 Zero S.  If you are interested in his observations comparing the two bikes you might want to check out his comments. He has now ridden his Zero over 20,000 miles since he bought it in April and his bike is now carrying a 15 kWh load.   https://www.facebook.com/lifeoffthegrid

[flar]

I've also ridden both - test rode them back to back on the same twisty road.  My general impression is that both are fast and both stop well.  The Zero is easier to get the power because all you do is twist your wrist and the 2013 motor is a monster.  The Empulse keeps some of that ICE concern over whether you are in the right gear, but at a radically reduced level - being in the wrong gear on an ICE bike can ruin the effort, but being in the "wrong" gear on the Empulse just makes it "a little less" impressive.  Off the line, the Zero still has a bit of that "easing you into it" feel on the throttle control, but the Brammo will kick you in the butt if you let it.  If you evaluate them solely on green light launches then the Brammo would win the seat of the pants test, but both would do the job with plenty of authority.

The thing that swayed me to get the Empulse was the chassis.  Every ride on the Brammo feels like you are connected to the ground.  The Zero chassis is very competent and feels safe, but when you are canyon carving it doesn't "inspire" confidence like the Empulse running gear.  Back to back on the same twisty road going as fast as I might care, the Zero felt fine, but didn't feel like it owned the road like the Empulse.

At one point I bought a german car and it taught me how to drive well.  I now drive an Acura that has been very cheap to maintain and I can drive it well, but it wouldn't have taught me what I know today.  I'll certainly learn a lot on the Zero and I would go farther at a time to do it, but the Brammo will teach me things.

[BrammoBrian]

At one point I bought a german car and it taught me how to drive well.  I now drive an Acura that has been very cheap to maintain and I can drive it well, but it wouldn't have taught me what I know today.  I'll certainly learn a lot on the Zero and I would go farther at a time to do it, but the Brammo will teach me things.

Good analogy.  The Empulse will reward good, smooth riding with some incredible performance.

[Shinysideup]

I haven't ridden the 2013 Zero yet, but of all the bikes I've owned for 40 years, when I commit the Empulse into a turn, it always answers me back in a very calm, reassured voice, "We can do this. We LIKE doing this. See ya on the other end."

[ttxgpfan]

I've also ridden both - test rode them back to back on the same twisty road.  My general impression is that both are fast and both stop well.  The Zero is easier to get the power because all you do is twist your wrist and the 2013 motor is a monster.  The Empulse keeps some of that ICE concern over whether you are in the right gear, but at a radically reduced level - being in the wrong gear on an ICE bike can ruin the effort, but being in the "wrong" gear on the Empulse just makes it "a little less" impressive.  Off the line, the Zero still has a bit of that "easing you into it" feel on the throttle control, but the Brammo will kick you in the butt if you let it.  If you evaluate them solely on green light launches then the Brammo would win the seat of the pants test, but both would do the job with plenty of authority.

The thing that swayed me to get the Empulse was the chassis.  Every ride on the Brammo feels like you are connected to the ground.  The Zero chassis is very competent and feels safe, but when you are canyon carving it doesn't "inspire" confidence like the Empulse running gear.  Back to back on the same twisty road going as fast as I might care, the Zero felt fine, but didn't feel like it owned the road like the Empulse.

This starts to confirm what I have only been able think, that the chassis handling of the Brammo is superior for the experienced riders., but beginner and new riders will find the Zero's performance easier to access.  Thank you for this.

Terry really had issues with the transmission feeling like it was going to break, which is a shame.

[FreepZ]

The discussion after the post was interesting.

In the argument of gears vs no gears, one point that nobody brought up was cost. As Brian Wissman pointed out last year in his ESBK interview; adding gears to the bike allows better performance at a lower cost.

Sure, the RR doesn't have gears, but it also has a very high voltage system, which is a lot more expensive than a lower voltage system. When high voltage systems get cheap, it will be possible to get RR performance without gears and at a reasonable price. Until then, there's going to be a trade off: Gears vs limitations on low end torque or top speed vs high cost.

[protomech]

FreepZ - possibly.

2013 Zero S is very, very close to Empulse performance. Similar quoted top speed (95 mph vs 105 mph), similar 0-60 times (~5.5s vs ~5s). I think from a 30-80 mph roll the Zero might even be faster.. and those speeds may well turn out to be more important on a racetrack.

Empulse weighs more, so it's impressive that the IET allows it to be faster even so. But how much of that weight is from the IET?

I don't think we'll have to go to IGBT mosfets ($$$) to get very acceptable performance from a single speed drivetrain, provided that 100-120 mph top speeds are acceptable. Empulse and Zero S comparisons are not just a question of IET vs single-speed, but just looking at specs the performance benefit seems to be small. We should be able to tell very soon whether there is a racetrack advantage, due to operating the motor at a more efficient point = less heat.

IET has significant weight, packaging, cost, complexity, and maintenance costs. The small but definite performance IET advantage (comparing the Brammo and Zero implementations) may be worth it, depending on the particular user preferences.

[Gavin]

Yep...both are good bikes.

It's (slowly) getting to be similar to ICE bikes...Both bikes will be well made, reliable and fun...the choice comes down to personal reasons...style preference...price...

like choosing a honda vs yamaha....or a bmw vs harley...

style
price
maybe a few other intangibles...like dealerships and such....

Gavin

[protomech]

I think there's a lot of intangibles. They're very close on specs; if either bike would be acceptable, then I think it's time to test ride both and determine which an individual user likes more.

It's worth noting that one person has done so (flar) and he bought the Empulse R : )

[Gavin]

Where you ride could be a big influence.

If doing mostly city, the Plus and the Zero bikes would be stellar. Lighter, very nimble. No clutch. Of course you could bypass the clutch for almost all city driving with the Empulse too.

If doing mostly highway and twisties, the Empulse would likely hold an advantage. The extra weight is actually very nice on the highway. More stable, less being blown around by trucks. And every rider has said the Empulse is crazy stable on mountain twisties. I'm sure the Plus and Zero bikes would do quite nicely in the twisties, but the Empulse would hold the road a bit better.

I still say that it will mostly come down to style. And the Clutch. Do you like a clutch or not? Do you like the Brammo Style or the Zero Style...and then, importantly, do you have a dealership in your town?


Gavin

[flar]

What clutch?  Oh that clutch.

I would consider clutch issues if not for:

- you don't need it for stop and go (no more cramped clutch hand in the city)
- you don't really need it for upshifts (the power train is very power shift-friendly)
- you sometimes don't need it for downshifts (I can usually get 2nd->1st to trigger coming to a stop, but less success on other gears)

When they started designing the (final version of the) Empulse there was no way they were going to get here without a transmission, but unfortunately the development time lasted long enough for motor development to catch up.  I imagine that cost might be lower with a transmission, but it's hard to gauge that from the evidence of the Empulse vs. 2013 Zero line.  But, when/if the e-moto segment takes off the economies of scale will do a lot to erase that cost advantage.

I've been telling people that this may be the only bike ever produced with a transmission - Zero is not likely to go there and by the time they bring out the Empulse's successor then high voltage will be cheaper and there will be nearly no need.  It would probably still have a transmission if it is a light spec upgrade like the Enertia -> Enertia Plus, but probably not if it were a new design/model.  On the other hand, Zero had to spend a bit of money designing a custom motor so it may not be possible to get to this level of performance without that kind of investment.

But, that's just a seat of the pants guess as to how the industry will evolve, I don't have much experience in electrical systems and motors.  I'm just watching what the industry is doing and garnering tidbits of information about the technology from these forums...

[ttxgpfan]

Flar, you have a pm.

[protomech]

I think some of it also depends upon your local charging infrastructure. Input power is fairly easy to compare, though I'm assuming charging efficiency is roughly comparable.

NOTE: charging rates compared below compare miles charged per unit time, not bike 0-100% charging

110V AC (conventional mains): Zero S charges 10% faster
Zero S and Empulse are both limited by 110V AC charging. Zero charges at 14A. I suspect Empulse charges around 14-15A on 110V. Obviously you're not going to charge quickly with either bike, but the Zero will charge around 10% faster if you must.

230V AC (J1772/conventional mains): Empulse charges > 2x as quickly
Empulse shines on 230V AC charging (whether from national plug or J1772). Empulse can pull 16A @ 230V AC, Zero S can pull 6.6A @ 230V AC. Empulse will charge > 2x as quickly. Note that J1772 is a $500 option for the Zero bikes.

Fast DC: Zero S charges > 4x as quickly as 230V AC Empulse
CHAdeMO charging stations are still pretty rare on the ground. Pretty fantastic if you live in an area with multiple CHAdeMO stations. Bit of a gamble otherwise.

Sounds like Brammo is betting on SAE combo DC for the future. That may well be the best technical solution - but CHAdeMO has a 3 year lead on infrastructure rollout.

I'd really love to knock some heads together over CHAdeMO and SAE J1772 DC. There may be a long-term gain to introducing a second recent DC-charging standard, but in the short term I feel like J1772 DC is very hurtful to charging infrastructure rollout and EV adoption.

The Chevy Spark EV is due to be released summer 2013, first EV with the SAE DC combo plug. 80% charge in 20 minutes is pretty hot.

[ttxgpfan]

Funny, I was typing for hours last night writing a post on this very subject.  If the Empulse doesn't have significantly faster 0-60 time then the transmission will be seen as all but pointless.  The transmission should ease the load on the drive system while better acceleration.  The Empulse as has liquid cooling.  The Empulse should be able to accelerate harder for longer everywhere.  The performance should be more more consistent at the very least.  If you want to go head to head with the ICE bike you have to have better numbers.  That's 0-60, 1/4 mile, lap times, and less important now a day is top speed as I am surprised to find.  I feel that even with 80kW you have to have a transmission be competitive.  I am suspect of a 5 second 0-60 on the 2013 Zero because it is air cooled, and the load that will put on the drivetrain.  I am waiting to be proven wrong, however.

[flar]

The dashboard reports 12Amp charging current for most of the charging cycle on the Empulse.

The rated time in the specs is 3.5 hour charging time for the Empulse on Level 2 and 1 hour charging the '13 Zero on CHAdeMO so not quite 4x.

I'm curious as to how CHAdeMO has a 3 year lead on charging infrastructure when stations didn't start appearing in the US until just the past couple of months?

Also, there is nothing in the literature that implies any support for J1772DC on the Empulse.  Has anyone seen any references to it being able to support the SAE DC standard later?  How hard would it be to develop a CHAdeMO to SAE DC adapter?