IMPORTANT ANNOUNCEMENT! NEWLY DEVELOPED BMC MOTORS!!!

[Tom]

I know for sure the new 35A controller will handle 51.2v nominal Lifepo4. As far as any higher than that, I will test to make sure when I get them in stock.

So is the "new" 35A controller different than the existing BMC 35A controller?

[hi-powercycles]

Yes. It is redesigned with much higher internal components. 100v rated FETs. I do not yet know what the voltage cutoff is. When I find out, I will pass on the info!

[solarbbq2003]

this is going to get confusing and difficult to compare motors from indian and chinese factories if the power ratings are made up arbitrarily, a motor will have a given continuous power rating no matter what voltage/current its tested on, calling the motors 400watt and 600watt and 1 kw but not based on a standard way of calculating continuous power rating makes it meaningless when comparing to other motors as its arbritary values ( i.e made up values).
You would have to define how you are getting these power rating values to have any meaning when comparing motors, ultimately how the motor performs is the most important factor.
What are the internal differences between the 400 and 600watt motors? are the windings different in any way?
Its almost certain the motor you are calling 400watt is the same as the chinese version which was called 350watt, but when tested its continuous power rating was in fact 250watt. So your 400watt motor would almost certainly be a 250watt rated motor if it was tested on a torque testing machine ( the graph data can be used to determine the continuous power rating), just using volts and amps isn't enough info to determine continous power rating.
Let me make a guess: your 400watt motor has two strand type windings in it, the other motor your calling 600watt should have a single strand type winding ( but almost certainly wont be 600watt rated more likely 350watt)
Personally I prefer to use max power ratings, the max the motor can handle without burning out if under load for some time, but there are conventions for continuous power ratings, which your not using, so although its nice to say 400watt and 600watt continuous power rated motors it doesn't really mean anything as the values your giving them are arbritary.
If you can give the winding resistances and number of strands in the windings then at least some comparison can be made to the chinese made motors, the point I was trying to make in an eariler post is that these motors are coming from india, based on technology/knowledge transferred from china, chinese have alot of experience with these motors over many years, india its a new thing to make these motors, so comparisons of indian and chinese motors would be quite valuable, other point I was hinting at is that there has been a long difficult process involved with the chinese bmc hub motors, likely a similar process will occur with the indian made ones. If the chinese/indian factories were in very close contact it might not be a problem, but it appears the ties are not very close.

[solarbbq2003]

to get a simple approximation of continuous power rating of a motor you can simply multiply the peak power by 3/16, or around 20% is a rough rule of thumb, to get the a more accurate figure would be complex as depends on alot of variables, but pretty much it means the power you could run the motor at continuously without the windings exceeding a given temperature, power is torque multiply by rpm, so you really need a torque graph to get some idea of the rated power ( continuous power) below shows the area that can be used as approximation of continuous power rating .
I'm no expert on these things but would be interested how you guys are coming up with 400watt and 600watt continuous power on the bmc india motors, can you give resistance values of the windings in the two different motors?

cont power about 20percent peak.jpg (41.8 KiB) Viewed 1697 times

[solarbbq2003]

heres a copy of a test i had done on a 350watt china bmc hub motor using 48v 20amp crystalyte controller
independent test not from bmc

bmc 350watt test data 241007.jpg (142.03 KiB) Viewed 1741 times

The torque testing machine gives a calculation of continuous power rating which came out at 250watt, using 20% of peak power output as rough estimate comes out a bit low in this case.

[solarbbq2003]

another thing of interest from the graph, they design the motor rpm for use on 36v, so in this test the rpm is 420rpm max no load at 48v, this motor was sent as a 320rpm motor. Max efficiency is 77% so they are loosing maybe 7% due to the gears, the motor alone without gears, efficiency would be around 84 or 85%. No load torque was a bit over 40Nm, not too shabby.

[solarbbq2003]

sorry I meant stall torque ( along bottom axis) was a bit over 40Nm.

[hi-powercycles]

Hello to everybody!
I have personally tested and also read all applicable Dyno sheets pertaining to the 400W, and 600W motors.

The 400W geared motor at its peak efficiency (about 78%) outputs 300-420 Watts. Above 420 Watts output, efficiency starts to slowly decline. At 36V and 16 Amps, 19 Newton-Meters of torque are present.

The 600W geared motor at its peak efficiency (about 76%) outputs 650-950 Watts. At this particular dyno testing, we terminated at 950 Watts output, while still in its peak efficiency range. Recently, I tested the motor at 1500W input and still got 1120W output power.... This motor in my opinion is underrated from the factory. On 48v and 26 Amps, 23 Newton- Meters of torque are present. Motor RPMS at peak efficiency are almost 50% higher than the 400W motor!

For those interested in hill climbing torque, the 600W motor is the clear champion because it can handle higher current loads much better than the 400W motor. The 600W motor with the Crystalyte 40A or the new BMC 35A controller would both be killer choices.

I also have preliminary test data on the new 1000W motor. Peak efficiency is about 84%. There are no gears on this one, so we will see how it stacks up against the 400W and 600W geared motors! Motor RPMs at peak efficiency are almost 50% higher than the 600W motor!

I will be conducting more tests early next week, including DIRECT head to head comparisons:
BMC 600W Thunderbolt vs. C-lyte 5304 vs. BMC 1000W (pre production test unit)
Should be fun!

P.S. NONE of these motors are made in the BMC India factory.

[Tom]

I thought the 1000W motor was the third one you described in the original post, i.e. "when you crave the torque to conquer any hill imaginable, then the new BMC striker is your ticket to the top!" If the 1000W has no gears I'd think the 600W would be better choice for hills?

[hi-powercycles]

Hi Tom,
It turns out at the moment, the striker is not available as of right now. I am looking into getting the thunderbolt re-wound for more torque and lower speed. I guess I will have to modify the initial post so that I don't confuse anybody. Thanks for your input

[Tom]

Thanks for clarifying. Is the "striker" just a custom build for you or will it be available from other BMC dealers? How long until we can expect it to be available?

[Microbatman]

The Thunderbolt sounds like a game changer.

Any pics of the proto-type?

When do you expect the Thunderbolt to be ready?

[John in CR]

These new BMC motors may very well be fine motors, but my question is when is the unfettered and unsubstantiated advertising going to stop. I mean there are other motors that are more efficient and other motors with proven track records, and most motors are more reasonably priced, so what's the 4 pages of excitement about? I'm sorry but if you have a manufacturer with a track record that is lacking, then at best there's an appropriate place to hype new models that you want to sell months ahead of time, which isn't here. Instead put some actual motors in reputable members hands and let's hear about some real world results instead of this blatant advertising blitz.

John

[Tom]

Hey John, personally I'm glad to hear about the new motors since they are what I've been hoping/waiting for, going on 2 years. Non-geared hubs don't work for my application. As far advertising, as long as it's contained to a single thread I don't see it as a big deal. The more information on new and upcoming models the better. I pre-ordered mine last week from a BMC dealer and he told me they should have them within a week. So they are here now, or will be shortly.

[shinyballs]

To you over excited readers.... don't get your hopes up.

Simply put, without any proof of existence and commercially availability -
consider this so called "motor" post VAPORWARE

[hi-powercycles]

Tom,
Sorry If I haven't been clear. The motors have already been for sale on our website: http://www.hi-powercycles.com/product.s ... oductId=23. We have already sold out of our first lot. You can look at the pictures of the actual motor on the website. I have had this motor on my personal bike for about 10 days now... We have more motors possibly coming in this week. Like I said earlier these "Thunderbot" motors weigh in at 8.9 lbs dry! (motor only)

Here are some pictures of the Thunderbolt on our website: http://hi-powercycles.com/images/122351 ... 74845.jpeg.

[TPA]

PRICE

[hi-powercycles]

Price will be $899 for 600W thunderbolt with standard 36/48v 25A controller, Twist grip throttle, anodized steel torque arm, and On/Off switch with inline (30A or 40A) fuse in a weatherproof case. Right now, pricing for limited quantities of Modified Thunderbolt with Crystalyte 24-72V 40A controller is $1249.

[pwbset]

:shock: PRICE

Yeah... saw that too. I'm sure these are nice and all, but I'd rather do a custom 5305/72v40a with 4+ah of LiMn and a cycle analyst for about the same cost.

(ebike.ca prices)
$515 - Rear 5305
$18 - 5-spd freewheel
$155 - 72v20a pedal first controller (solder shunt to 40a)
$15 - twist throttle
$125 - Cycle Analyst
$360 - 72v4.4ah Lithium
$50 - shipping
$1,238 Total to you door...

EDIT: For what it's worth I'm not knocking hi-powercycles pricing models... I'm just a comparison nut and a bargain hunter... and most importantly.. broke.

[hi-powercycles]

Hey, that sounds like a great deal! For us, we purposely chose not to sell the Crystalyte 23 lb X5 motor because it undermines our motto of high performance and light weight... If weight is not a big concern, x5's are great!

[Tom]

delete

[solarbbq2003]

how about some torque graphs/pics of internals? my sources are saying these come from india factory so will have to disagree with you there, doesn't really matter as long as they are as good a quality as the chinese factory motors ( which are top notch)

[hi-powercycles]

Hello everybody,
I actually have some more really good news! I got the first 1000W test motor in! We are calling it "Black Lightning." The motor itself is a nice classy black finish. The shocker here is that the motor only weighs in at 10.3 LBS!!!! Yes, that is not a misprint, The motor fully spoked in a 26" rim with rim tape weighs in a total of 11 lbs, 14 oz. Top speed should be more than 40 MPH at 48V. We are targeting the crystalyte X5 with this one. The actual size of the motor is the same as the 400 and 600W motors... However, this motor is not geared.

I took the motor for a quick spin tonight... It was a fast motor, and also extremely quiet. I will check the speeds I get with a 16 cell Lifepo4 pack and the new BMC 35A controller (with paralleled IRFB 4110 FETs).

[hi-powercycles]

Here is a pic of the 1000W motor!

[GGoodrum]

Well, if it is not geared, I'd be very surprised if this would come close to matching the torque of a 5304. Maybe a 4 series. The whole advantage of using a BMC-type motor has been having the torque advantage of the gearing. The problem up to this point has been that when you try to get similar performance to an x5 out of these, the nylon gears couldn't hack it. The metal-on-metal gears handle the power a bit better, but are noisy and waer quickly. The new composite gears, and the higher power version (600W...), sound like big improvements, indeed, but this 1000W looks like nothing more than yet another smallish hubmotor. I'd be a little careful with laying on the superlatives, at least until you've tried it.