Conclusive proof gearboxes are awesome.

besi said:
I don't know if this video was previously posted on this thread but something like this could make a gb for ev useless: [youtube]YaIwTTpztaI[/youtube]


Im afraid those brilliant core-loss reducing and kv altering very cool tricks can only make a GB for an EV more un-needed, rather than making it un-needed in the first place.

What's painful to see in the above stuff is people still saying large direct-drive means bigger batteries and/or lower efficiency.

If done right, it IS the most efficient period. This means smaller battery if you choose to have the same range.
 
Here's a thread on the SMRE gearbox that Brammo have incorporated:
http://www.endless-sphere.com/forums/viewtopic.php?p=363695#p363695

Also: http://thekneeslider.com/brammo-6-speed-integrated-electric-transmission-from-smre-engineering/
 
Anyone know how SMRE's stuff has turned out?

My only personal experience involved hearing the difficultly was not being geared correctly for the track as the excuse. Which is a funny thing to say to a single speed direct drive rider when you had 6 choices to his 1 to get the tracks gearing right during the race. But I think the problem was that the rider had the really quite substantial disadvantage of having a narrow-ish rpm range in which his motor was capable of extracting the power it needed from it without melting. The bigger motor running always at beneith its capacity except when you're asking for peak output at peak rpm, is on the constantly taking it easy and ready to make the bursts of torque you're requesting as a rider without having to be distracted into always needing to fumble a lever with a toe while bouncing around on dirt or trying to lean over for the twisties tucking your feet up from getting down so low, which is why sportbikes use electric shift devices for handling this at a surprisingly grass-roots level. It's a burden to shift if your resources as a human are needed for 100% focus to be riding as well as possible.

This is why you hear the rider for the mugen TT bike, the best most ballsy isle of man rider of all times, say his favourite thing about the bike was no transmission and no shifting. Just always the power he wanted to the wheel on command, no fumbling with toes and levers and buttons and things, just riding.
 
liveforphysics said:
What's painful to see in the above stuff is people still saying large direct-drive means bigger batteries and/or lower efficiency.

If done right, it IS the most efficient period. This means smaller battery if you choose to have the same range.


so your saying you dont need more battery's, even when the motor is heavier so if you have a bike that has a 10kw motor fitted and is running very efficiently but then change the 10kw motor for a 50kw motor and matching controller ( for better acceleration ) and top speed is unchanged your saying that you will get exactly the same range from the battery's ?

If a e-TT bike can do 130mph average lap speed ( 37 miles per lap ) (200mph max speed ) ( e-TT bikes do a max speed of around 170mph )around a road circuit as this will be a direct comparison with the gas TT bikes , but the e-TT bikes cant achieve those average speeds and that distance I personally think it could be achievable with the use of a couple of gears. Was the Brammo bike running gears when it beat everything else in the Daytona 2012 TTXGP world championships ?.
 
Looks like Justin ebikes.ca thinks 2 speed hub motors are awesome
Technically it doesnt have a transmission :D
It does have gears though 8)

Bidirectional hub motor with unidirectional two-speed output
US 20120302390 A1
ABSTRACT
A two-speed bidirectional hub motor includes an electrically driven hub, including an electrical motor, oppositely aligned one-way bearings, and a planetary gear system connected to the electrical motor. A fixed shaft is connected to the stator of the electrical motor. The first of two one-way bearings connects the electrical motor to the planetary gear system, and the second one-way bearing connects the electrical motor to the hub casing. When the rotor is electrically activated to spin in the forwards direction, the second one-way bearing engages the hub casing and rotates the wheel forwards at high speed. When the rotor is electrically activated to spin in the reverse direction, the first one-way bearing engages the planetary gearing system, rotating the wheel forward at lower speed by a gear reduction. This design gives two-speed output without a transmission.
 
gwhy! said:
liveforphysics said:
What's painful to see in the above stuff is people still saying large direct-drive means bigger batteries and/or lower efficiency.

If done right, it IS the most efficient period. This means smaller battery if you choose to have the same range.


so your saying you dont need more battery's, even when the motor is heavier so if you have a bike that has a 10kw motor fitted and is running very efficiently but then change the 10kw motor for a 50kw motor and matching controller ( for better acceleration ) and top speed is unchanged your saying that you will get exactly the same range from the battery's ?
No you do not need more batteries. As we have said you pick your pack for range no peak amp draw because when you get decent range you have more then enough amps available.
BOTH BIKES weigh more adding a transmission adds weight as does using a bigger motor but fore a very small increase in motor size you get HUGE gains in power then you do need a bigger controller. But as Luke points out this makes a more efficient system then a transmission because the motor will not be stressed most of the time.

Its really amazing how many pages of going back and forth on this people can go though and not get it. BIFF and Chalo both pointed out there is times either will be better but in the end if you have a choice to add a bigger motor or a tranny and all other things aside why is it so many think a transmission is a better way to go??

I see it like this a bike with no motor and just a transmission can not move
A bike with a motor and no transmission can work fine. So by this math in most cases transmissions are dead weight/drag on the system.

Transmissions will have a place like behind a ICE where there is 0 torque at 0 rpm but its just non sense if you have the option of a bigger motor/controller.
 
flathill said:
Looks like Justin ebikes.ca thinks 2 speed hub motors are awesome
Technically it doesnt have a transmission :D
It does have gears though 8)

Bidirectional hub motor with unidirectional two-speed output
US 20120302390 A1
ABSTRACT
A two-speed bidirectional hub motor includes an electrically driven hub, including an electrical motor, oppositely aligned one-way bearings, and a planetary gear system connected to the electrical motor. A fixed shaft is connected to the stator of the electrical motor. The first of two one-way bearings connects the electrical motor to the planetary gear system, and the second one-way bearing connects the electrical motor to the hub casing. When the rotor is electrically activated to spin in the forwards direction, the second one-way bearing engages the hub casing and rotates the wheel forwards at high speed. When the rotor is electrically activated to spin in the reverse direction, the first one-way bearing engages the planetary gearing system, rotating the wheel forward at lower speed by a gear reduction. This design gives two-speed output without a transmission.
This again is for a law that limits motor size. Justin would say if the law allows a bigger motor go for a bigger motor.
 
Arlo1 said:
Its really amazing how many pages of going back and forth on this people can go though and not get it. BIFF and Chalo both pointed out there is times either will be better but in the end if you have a choice to add a bigger motor or a tranny and all other things aside why is it so many think a transmission is a better way to go??

I think this sums it up best, the application determines what is best to use IMO, i.e if you dont have the room for large motorcycle size motors on your e-bicycle
then a smaller motor with a transmission might fit the bill lil better? alternatively, if space is not an issues a bigger motor to do a similar job a little more efficiently is the shot... :wink:

Personally, i still think mushing through gears is fun and sounds hell cool, so they get my vote... :mrgreen: efficinecy-schmicency pft..just add a couple more lipo bricks and mash away on 'dem gears bois..LoL :p


KiM
 
Arlo1 said:
gwhy! said:
liveforphysics said:
What's painful to see in the above stuff is people still saying large direct-drive means bigger batteries and/or lower efficiency.

If done right, it IS the most efficient period. This means smaller battery if you choose to have the same range.


so your saying you dont need more battery's, even when the motor is heavier so if you have a bike that has a 10kw motor fitted and is running very efficiently but then change the 10kw motor for a 50kw motor and matching controller ( for better acceleration ) and top speed is unchanged your saying that you will get exactly the same range from the battery's ?
No you do not need more batteries. As we have said you pick your pack for range no peak amp draw because when you get decent range you have more then enough amps available.
BOTH BIKES weigh more adding a transmission adds weight as does using a bigger motor but fore a very small increase in motor size you get HUGE gains in power then you do need a bigger controller. But as Luke points out this makes a more efficient system then a transmission because the motor will not be stressed most of the time.

Its really amazing how many pages of going back and forth on this people can go though and not get it. BIFF and Chalo both pointed out there is times either will be better but in the end if you have a choice to add a bigger motor or a tranny and all other things aside why is it so many think a transmission is a better way to go??

I see it like this a bike with no motor and just a transmission can not move
A bike with a motor and no transmission can work fine. So by this math in most cases transmissions are dead weight/drag on the system.

Transmissions will have a place like behind a ICE where there is 0 torque at 0 rpm but its just non sense if you have the option of a bigger motor/controller.

Your assuming that the GB will be big and heavy ( it might not be ) we know for a fact that the motor will be much heavier and bigger so lets say yes you will need more battery due to the additional weight of the motor. Look at it this way if using a GB small and light and because we can use this GB this will also allow to use a smaller lighter motor for the same performance and this will also mean less battery for the same performance .
 
John in CR said:
Has a multi-speed electric ever won a race other than against another multi-speed?

Case dismissed.

Thats what I was asking :

Was the Brammo bike running gears when it beat everything else ( including modified zeros ) in the Daytona 2012 TTXGP world championships ?.
 
gwhy! said:
John in CR said:
Has a multi-speed electric ever won a race other than against another multi-speed?

Case dismissed.

Thats what I was asking :

Was the Brammo bike running gears when it beat everything else ( including modified zeros ) in the Daytona 2012 TTXGP world championships ?.

I have a quick look around the web and as far as I can make out it was running with a gb...
 
John in CR said:
If it did, it certainly wasn't because it had a gearbox.
hahaha i think its a bit unfair to say now it wasn't because it had a gearbox because you was the one who asked.. :)
 
Arlo1 said:
flathill said:
Looks like Justin ebikes.ca thinks 2 speed hub motors are awesome
Technically it doesnt have a transmission :D
It does have gears though 8)

Bidirectional hub motor with unidirectional two-speed output
US 20120302390 A1
ABSTRACT
A two-speed bidirectional hub motor includes an electrically driven hub, including an electrical motor, oppositely aligned one-way bearings, and a planetary gear system connected to the electrical motor. A fixed shaft is connected to the stator of the electrical motor. The first of two one-way bearings connects the electrical motor to the planetary gear system, and the second one-way bearing connects the electrical motor to the hub casing. When the rotor is electrically activated to spin in the forwards direction, the second one-way bearing engages the hub casing and rotates the wheel forwards at high speed. When the rotor is electrically activated to spin in the reverse direction, the first one-way bearing engages the planetary gearing system, rotating the wheel forward at lower speed by a gear reduction. This design gives two-speed output without a transmission.
This again is for a law that limits motor size. Justin would say if the law allows a bigger motor go for a bigger motor.

Which law that limits motor size? You mean power output? I would like to hear from Justin myself rather than hearing someone speak for him

-------
The Brammo race bike was running single speed
Thee excuse they use why they dont run the same on the empulse
High voltage pack I think like 300v but not positive

What I think e motorbikes will dominate on the race track with a single speed for sure
Now at an electric 24 hour le mans with a heavier car a multispeed speed will win
The only way to end the back and forth arguing is on the track
 
flathill said:
Arlo1 said:
flathill said:
Looks like Justin ebikes.ca thinks 2 speed hub motors are awesome
Technically it doesnt have a transmission :D
It does have gears though 8)

Bidirectional hub motor with unidirectional two-speed output
US 20120302390 A1
ABSTRACT
A two-speed bidirectional hub motor includes an electrically driven hub, including an electrical motor, oppositely aligned one-way bearings, and a planetary gear system connected to the electrical motor. A fixed shaft is connected to the stator of the electrical motor. The first of two one-way bearings connects the electrical motor to the planetary gear system, and the second one-way bearing connects the electrical motor to the hub casing. When the rotor is electrically activated to spin in the forwards direction, the second one-way bearing engages the hub casing and rotates the wheel forwards at high speed. When the rotor is electrically activated to spin in the reverse direction, the first one-way bearing engages the planetary gearing system, rotating the wheel forward at lower speed by a gear reduction. This design gives two-speed output without a transmission.
This again is for a law that limits motor size. Justin would say if the law allows a bigger motor go for a bigger motor.

Which law that limits motor size? You mean power output? I would like to hear from Justin myself rather than hearing someone speak for him

-------
The Brammo race bike was running single speed
Thee excuse they use why they dont run the same on the empulse
High voltage pack I think like 300v but not positive

What I think e motorbikes will dominate on the race track with a single speed for sure
Now at an electric 24 hour le mans with a heavier car a multispeed speed will win
The only way to end the back and forth arguing is on the track
I don't think even on the track you cant stop the arguing. I think this question is to complex to give it a clear respons. In every case it's different. Like you sad in a car on the 24h of Le Mans a multispeed would win and in a race motorbikes direct drive would dominate. I think you can not give it a general decision for every vehicle. It depends on the case it's self. It depends on to many variables.
 
besi said:
Chalo said:
h0tr0d said:
Here's a total fail when a guy wanted acceleration, top speed and was also "allergic to transmissions". :mrgreen:
http://en.wikipedia.org/wiki/Eliica
8 wheels with DD motors!

8 wheel drive and a demonstrated 230mph is a fail to you?

Each of the wheels has a 60 kW (80 hp) electric motor, giving a 480 kW (640 hp) eight wheel drive which can tackle all kinds of road surfaces.

There are currently (as of 2005) two versions of the Eliica: a Speed model and an Acceleration model. The Speed model is made to challenge gasoline-based records and has a top speed of 370 km/h (230 mph) with a range of 200 km (120 mi). The Acceleration model is made for the street and has a top speed of 190 km/h (120 mph) with a range of 320 km (200 mi).
Not fail having 480kw and just doing 190km/h that is doable from a 80kw diesel family sedan. hahahaha

It's not making 480hp at 190 klicks. Not even close. But why should it? If your car doesn't need to go 190km/h (like for instance if that would land you in jail), then why not gear it for the speeds that are reasonably foreseeable? 0-60 in 4.0s and 120mph in a hurry is pretty awesome. 8-wheel drive and 8-wheel regen are also pretty awesome. I don't even like cars and I think it's rather cool. If you're some kind of Saudi prince and you can go 230mph when you like, well there's a model for that too.

A 480hp supercar may be making that much power at top speed, but it isn't doing it at around-town speeds without blowing away the tires and summoning the police. But the Eliica is-- quietly and reliably, too. No transmission, drive shafts, or gears to break, wear out, or make a racket.
 
What do you think about the fact they determined they needed a speed model and an accel model with 8 hub motors?
Sounds like they could use justins two speed hub motors to do both
However they were constrained

We need a two speed hub motor with regen ability
 
John in CR said:
Has a multi-speed electric ever won a race other than against another multi-speed?

Case dismissed.

Case re opened !
Well the fastest EV drag car in the world currently is Black Current III.. a 2 speed transmission .
Lots of other EV drag cars in the comp, some with DD.. ( such as the predecessor.. Black current II, W't Zombie, etc )

But this is a silly question and proves nothing, as there are so many other differences to consider.
 
flathill said:
Which law that limits motor size? You mean power output? I would like to hear from Justin myself rather than hearing someone speak for him
I would be supprised to see Justin post here maybe you can email him.

I live in the same province under the same laws as justin. The motors rating is what ICBC rates their power based on. It used to say Max continious rating of 750watts for ebike now its 500 watts. http://www.icbc.com/registration-licensing/offroad-other/low-powered/motor-assisted
 
flathill said:
What do you think about the fact they determined they needed a speed model and an accel model with 8 hub motors?
Sounds like they could use justins two speed hub motors to do both
However they were constrained

We need a two speed hub motor with regen ability

If you need to go faster than 120mph, sure. But not on public roads in this continent.
 
gwhy! said:
gwhy! said:
John in CR said:
Has a multi-speed electric ever won a race other than against another multi-speed?

Case dismissed.

Thats what I was asking :

Was the Brammo bike running gears when it beat everything else ( including modified zeros ) in the Daytona 2012 TTXGP world championships ?.

I have a quick look around the web and as far as I can make out it was running with a gb...


Nope. Every race bike I've seen them race is single fixed ratio direct drive. Its a good way to do it.
 
flathill said:
We need a two speed hub motor with regen ability

You're behind the times. I have several, my son a couple, JRH has one as do some other forum members. My 6 phase single speeds are better though. :mrgreen:
 
John in CR said:
flathill said:
We need a two speed hub motor with regen ability

You're behind the times. I have several, my son a couple, JRH has one as do some other forum members. My 6 phase single speeds are better though. :mrgreen:

Going 6 phase does give a few advantages in winding factor optimization that should be good for a few fractions of a percent less motor losses, but from a high power at low-ish voltages perspective, should make leveraging existing controller technology and controller efficiency. That makes it a good thing for folks looking to milk big power at low voltages with economical controllers, while getting a very tiny winding factor improvement that helps in a similar way to a copper-fill percentage increase to a motors continuous torque abilities if done in a way to improve winding factor from the previous 3 phase patterns winding factor.
 
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