So : who's tempted to build Luke's Goldenmotor mach 1 bike?

[drewjet]

Interesting new measurement Luke. Can you add the Etek, Astro and the Agni motors?

[neptronix]

Hm, this could explain the torque of the Magic pie. It's definitely up there.
Even on 57V / 33A, it was a wheelie machine.

Your recommendation did not fall short. Now you got me wondering why this motor has got little to no air time on ES, and Crystalyte has always been worshipped..


I find it quite amazing that there is something that already bested your golden motor chain drive setup years ago.
Kinda makes me laugh to think that we haven't even touched the tip of the iceberg yet..

[Philistine]

Now you got me wondering why this motor has got little to no air time on ES, and Crystalyte has always been worshipped..

Probably because it's name sounds like Harry Potter just shot one off and it has a paintjob that looks like it was designed to appeal to people high on acid.

But I don't think Crystalite has been worshipped necessarily, just that people have appreciated its heat shedding ability (the X5's anyway). That is pretty much the sole thing I have loved about my X5 motors, that I have never ever had to worry about heatsoak.

I don't think you could say that much of the commentary on the Hx motors has been particularly lauditory.

Lots of members (Toolman2 comes to mind), have been long time advocates of the Pie. I personally think that the whole internal controller in the wheel model put the extreme modders off, but I could be wrong. Ever since I had a go of Toolman2s I have thought about picking one up for my next hub.

[John in CR]

Not to be nitpicky, but the OD of Hubmonster's tire is 18.75", so that puts Luke's cool MTU# at 7323. That tells me that once I install welding cables, I mean phase wires, and get a proper controller, that my SuperV driven by Hubmonster really is the new Sheriff in town. I guess that means I need to spring for some of those highest C rate nanotechs too if I'm going to do the bike justice. BTW, yes the stator really is 270mm.

I've been spending all my time on these much higher efficiency hubbies lately, but now I really can't wait to get my mitts on their higher power high efficiency model. It's rated at 7kw compared to Hubmonster's 3.5kw rating, so it will be interesting to see it's stator dimensions along with how the claimed motor specific 6 phase controller actually works.

John

[nechaus]

where can i get your hub motor from john?

[Idontwanttopedal]

I seconded that where can you get them

[Andje]

I know im counting my chickens, but I, like Farfle am rewinding a double motor; two methods pre-buy hs30's. So that's a 198mm diameter stator with 60mm width.
That gives 6*19.8*3.14*(19.8/2)= 3693
20"= 4431
24"= 3693
26"= 3397

I'm pretty happy with those at the edge of destruction numbers, although still no where close to hubzilla...

[John in CR]

I seconded that where can you get them

I got mine used, but in like new condition from a forum member. I think KellyController has even bigger ones which have identical covers, so same diameter stator, and the greater weight must mean a longer stator and magnets. It's the high speed versions that you want unless you're planning to cannibalize one to put a bigger rim.

Finding a high power hubbie isn't the issue. In fact that's pretty easy as is fabbing a bike or swing arm to mount one. The issue is finding controller that can survive pushing these big motors to their limits. Luke's performance is mostly a result of the incredible amount of work put into properly tuning his 96 fet controller to drive the motor. It's not just the work effort either, but a unique combination of resources and skill sets.

[Arlo1]

** Note, I would like to clarify somethings before presenting my calculations for these various hubs.

This is a super crude possible torque index based just off the idea that you can saturate the whole flux gap area with a given amount of flux. The motors with lots more copper and mass are the only ones that can survives this absurd torque condition for more than a second or two, and that's why your x5 rips and survives it where the lighter hx35 would go pop, but just before it popped, it should be capable of these relative torque outputs.

That's why it's my own screw-ball goofy unit, made up just for the wacky mad scientist types who are looking to push these limits of exploding the motor (and likely the controller as well) for 2 seconds of intense thrust.

As a unit to relate how one motor will perform over another in the real world, or which will deliver a better riding experience, or which will win on the track, it's completely useless.

It's just a goof-ball unit to relate which could produce the biggest torque before it exploded into plasma, and it may not even be correct for that, because it's based on the assumption that they all would be using the same materials with roughly the same saturation flux density in this gap, and I am not a motor expert by any means, so it's just my best guess work.

LUKE,
I dont understand your math but how many "MTUs" would a cromotor have?

Clyte 40x series = 4.2cm * 17.1 *3.14 * (17.1/2) = 1,916 MTU

Clyte 530x series = 3.3cm * 20.5 *3.14 * (20.5/2) = 2,177 MTU

Clyte 540x series = 4.0cm *20.5*3.14 * (20.5/2) = 2,639 MTU

9C = 2.8cm*19.8*3.14* (19.8/2) = 1,723 MTU

Clyte HT/HS35 3.5cm 19.8*3.14 *(19.8/2) = 2,154 MTU

CroMotor 5cm*19.8*3.14 *(19.8/2) = 3,077 MTU

MagicPie 1.8cm*3.14 *26.5*(26.5/2) = 1,984 MTU

The larger diameter CroMotor 2.3cm*3.14*26.5*(26.5/2) = 2,535 MTU

The Farfle custom 2pi = 3.6cm*3.14*26.5*(26.5/2) = 3,967 MTU

JohnInCR's HubZilla = 5.0cm*3.14*27.0(27.0/2) = 5,722 MTU

My deathbike 6,574 MTU


To be perfect, this unit should have winding factor included (the average ratio of teeth from a given phase set that are lined up properly with magnets when energized), except... it's between 0.93 and 0.95 for all these motors, so I'm just neglecting it. Also, I realized that Pi is a comonality, and this is a comparison unit, so it could be dropped... but I all ready put it in, it's my unit, and it doesn't cause any harm.

So, this unit estimates that for a given stator material saturation (which is about 2T in normal stuff, some RC stuff may have exotic cobalt alloys and be a little higher, but hubs are all the same stuff), the theoretical torque it could achieve if you were sending it every bit of power it could handle until it was at the limit of saturation. So, to determine a way to relate acceleration capability (or thrust), we need to relate to tire size as well. So, I'm going to call 24" tire a 1 multiplier (because it makes things easy when thrust is also ft-lbs of torque). This means a 20" wheel would be a 1.2 multiplier, and a 26' wheel would be a 0.92 multiplier, and a 29" wheel would be a 0.82 multiplier.

Ok so I have been playing with these numbers...
I am building a hybrid scooter for my girfriend out of a working yamaha BWS and a motorcycle stator. seen Here

So the stator is about 4.75" dia and 3/4 inches wide so 11.875 cm x 1.875 cm
and I have 2 12kw colossus motors and their stator is about 10cm x 6.5 cm so for the calculations
My Gfs scooter 1.875 x 11.875 x 3.14 x(11.875/2) = 415 BUT its current gearing is 14.5:1 so 415 x 14.5 = 6019 MTU This is not the gearing I will be using and it might not be able to rev that hi.... But sure has potential on paper!
And colossus 10 x 6.5 x 3.14 x(10/2) = 1020.5 and my gearing on my YSR is 4:1 so 1020.5 x 4 = 4082 MTU
Now lukes motor is ~85% efficient and colossus is ~95% from the tests others have claimed.
So 4082 x .95 = 3877 for colossus
and 6574 x .85 = 5587 Hmmmm. Wow. SO the one thing with all of this is efficiency usaly drops as you add watts..... Very interseting on paper!

[neptronix]

http://kellycontroller.com/brushless-hub-motors-c-21_62.html

http://kellycontroller.com/hub-motor-72v-6kwdisc-brake10-inch-p-41.html

This bad boy has axle flats and all that stuff..

None of these are suitable for a regular bicycle chassis though. After the tire is fitted, they are like the equivalent of 12-16in. bicycle wheel sizes. Bummer for those who cannot weld, or live in a place where they have ebike power laws, lol.

One of these would be bitchin on a light scooter though. Stick 20kW into one of these hubs, and ...

[John in CR]

Those in the 10" or 12" rims are the smaller diameter motors. Based on Lukes numbers you'd want those with the 13" rims. Hubmonster's cover doesn't stick out of what appears to be the same width rim, so that 7kw bad boy is the one Luke will want. A wild guess from the photos is telling me 270mm diameter by 75mm thick stator. It's definitely substantially thicker than mine at 50mm.

The insides are absolutely cavernous on these motors, so an active ventilation approach like Arlo1 did with his X5 has huge potential. Plus with proper exhaust holes at the very perimeter could mean tremendous flow even without going active due to the large diameter.

My approach would be a combination with fans block the spokes except for some fans sucking air from one side and putting both intake and exhaust holes in only one side cover. The purpose would be to suck air to the closed half, so it's return flow would be through the magnetic gap and out the exhaust. I'll document mine if I ever get a controller that can push Hubmonster hard enough to get hot.

John

[lostrack]

Bump.
So, who is building a FAST bike right now?
Chime in, please do...

[grindz145]

Bump.
So, who is building a FAST bike right now?
Chime in, please do...

Define fast... Define bike...

[lostrack]

Bump.
So, who is building a FAST bike right now?
Chime in, please do...

Define fast... Define bike...

Er... See Luke's commuter

[grindz145]

I'm working on a more conventional motorcycle build. Only about 20hp. Nothing earth-shattering when compared to Luke's bike. I've been going back and forth on the design so much that I haven't bothered posting yet. But all in all my electric motocross bike won't be that interesting of a build by comparison.

[Haste]

that much power with just an etek motor..the same motors on egay for only 400?

[Dauntless]

So how does the Death Bike fit into the racing classes? They just say 'Unlimited' and that's that?

that much power with just an etek motor..the same motors on egay for only 400?

Hate to think of what they'd use that motor for. Redefines 'Broke Back Mountain.' (Some typos it's just impossible to pass up the response.)