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[Crissa]

Why would they get hotter than stationary motors?

-Crissa

[Fran K]

I guess a hub motor would be an outer rotor type surrounded by a planetary gearset.

[princec]

Doubtful it'll go to the expense of planetary gears. Most likely just straightforward direct drive, and too weedy to worry a lot about cooling.

Cas

[ultrarnr]

Well there is nothing on the Lightning web site about the Sparc so I guess they don't want anyone to know anything about it. Of course there isn't anything about the basic model of the Strike either and they are supposedly in production.

[Richard230]

Why would they get hotter than stationary motors?

-Crissa

The hub motors that I have seen are sealed and do not appear to have any cooling vents.  That was a problem with the Vectrix scooters, they couldn't handle long uphill runs (like 5 minutes) on the freeway without overheating, according to period test ride reviews.

[wavelet]

Why would they get hotter than stationary motors?

-Crissa

The hub motors that I have seen are sealed and do not appear to have any cooling vents.  That was a problem with the Vectrix scooters, they couldn't handle long uphill runs (like 5 minutes) on the freeway without overheating, according to period test ride reviews.

I read about them in the context of (lack of) suitability for the faster e-bicycles.
IIRC, Cooling vents are a problem because the wheel can easily fling dirt/liquids into the vent; adding active cooling (ducted fan or liquid) is awkward because of the location.
If the motor is small enough, it could be on the end of the swingarm and directly drive the axle, rather than using an actual hub motor. My 2-stroke Vespa had that design, and had very effective ducted-air cooling for the engine & transmission. Top speed was 65mph, but horrible handling.

[HoodRichOG]

80mph on a hub motor and with 12" wheel? Sorry, I'm having a hard time believing it.

Also, handling with that hub motor will make this thing a turd, especially at 80mph.

[princec]

Agreed, it's pure fantasy.

Cas

[Crissa]

Hub motors are pretty light now, and cooling is not a problem if you ise the centrifugal force generated like a blower over the inductors (or whatever they're calling the magnetic plates).  And there are plenty of proof of concept models out there using hubs to go quickly.

Will they meet their price and performance points?  Dunno.  Do I think sam is lying?  Why would he?  Are they plausible?  Nothing says otherwise.  There's just not enough hub motors in long service to know.

Is calling a design excrement useful to the forums?  I don't think so.

-Crissa

[wavelet]

80mph on a hub motor and with 12" wheel? Sorry, I'm having a hard time believing it.

To be fair, I don't think it's certain that those are 12" wheels. They looked about the relative size of a Honda Grom's (which does have 12"-ers) in the picture, which is why I asked Sam if he happened to notice.

This would be a commuter (the dual-sport style notwithstanding), so it's also possible the top speed is a misunderstanding, and it's 80 km/h, not mph. That would make a lot more sense, at the price mentioned, and in line with lower-end electric commuters by other companies.

[togo]

> ... and it's 80 km/h, not mph. That would make a lot more sense,

Oh, barely freeway legal in USA.  That makes more sense.

[NEW2elec]

Yeah not for me.  My 13 year old self would have loved it though.
I don't want to seem like I'm piling on Lightning but this bike seems like a 100% Chinese idea, design, build, and intended for the China market only.

 "Here you sell our bike in the US we'll make you a cheap Strike bike sure no problem.  You go sell my bike now.  Tell me when you need more Sparc bikes we'll send them to you."

To me even in a dense US city a high end E bicycle is such a better choice, since most can be lifted and taken indoors after a short commute.

[wavelet]

Yeah not for me.  My 13 year old self would have loved it though.
I don't want to seem like I'm piling on Lightning but this bike seems like a 100% Chinese idea, design, build, and intended for the China market only.

 "Here you sell our bike in the US we'll make you a cheap Strike bike sure no problem.  You go sell my bike now.  Tell me when you need more Sparc bikes we'll send them to you."

To me even in a dense US city a high end E bicycle is such a better choice, since most can be lifted and taken indoors after a short commute.

Likely, since the US power limit on e-bicycles is 750W Federal, and some states (IIRC California included) go up to 1000W, and throttle control is fine; in Europe and many other places, the limit is 250W, and only assisting pedaling is allowed, no pure throttle motor use.
That said, I can see someone who doesn't have a freeway as part of their commute being OK with it, esp. in areas where there aren't decent bike paths -- it can still accelerate as well as many cars on surface streets -- as long as they have decent parking options.

[mistasam]

so it's also possible the top speed is a misunderstanding, and it's 80 km/h, not mph.

There's a stretch of road on my commute that's 70km/h, so I know what that feels like, and the Sparc was absolutely in mph.  You can kiiiinda tell from the video how quickly it accelerates.  The thing was surprisingly fast, especially compared to a Grom.  And the Grom has a top speed of 110km/h if you're going downhill, so something with 3x the power should be able to do ~130km/h (80mph).

As far as the bikes being made in China, I was told that it was a collaboration between Lightning and their partners over there.  Richard said all the internals (battery, controller, etc) are Lightning.  If you guys find a link to one of these bikes on Alibaba that has 30hp and sells for $5k usd, let me know 

[Fran K]

This electric stuff needs some convention.
30 hp is what about 30 peak and about 10 continuous.  If I recall a BMW r50 goes about 80 with the elbows clamped to the sides not even in a full crouch.  That was 26hp do not recall exactly what measuring system.  Apparently for the European liscencing they go by continuous hp.  The new KTM freeride is 24 peak, 8 continuous.  Then the way to rate the battery is kind of fudged using peak volts X amp hours instead of the nominal way.

Kind of amusing I see that as a pit bike the kind of thing folks ride around the parking Saturday evening before the race on Sunday.