snowranger
10 kW
I have talked to Ilia, and he did say that the V4 is a new version. Going to be pricey though. Wish those $300 clearance motors from hipower were still around.
BMC V4 motor
- Thread starter mikhogl
- Start date
oatnet said:
I think these 'V4' will be the same one that Hi-power cycle try to sell as their presale. Basically you get the new clutch, supposively wider gears, and more copper in the motor, dual phase wires and slightly heavier. Other than that, I don't know of any more "upgrades."
Wider gears and better clutch = means you can accelerate faster without stripping the gears and they will last long. The new wider clutch also freewheels better, though I doubt you will see much benefits. Maybe wider clutch means less chance of clutch going out if you accelerate too fast?
more copper in the motor = slightly better efficiency, but not much. Maybe 2-3% is my guess. Again I don't know how much it would matter.
dual phase wires (9 gauge equilvant = means you can put more power into it without worrying about phase insulation melting due to heat generated from input current and wire resistance.
All in all, I think you still have problems with heat. Even if you can put more power into the motor, the heat is still there and still can melt the wires from the outside in as oppose to inside out. And if you are going fast to begin with, it probably wouldn't even matter since phase current is reduced by back EMF.
I would wait to see the results before I buy. That was one of the reason why I did not buy during the presale. But I think this time, they really stepped it up compared to MAC motors. My guess is MAC motors will soon follow suit. So it might be best to wait to see what cellman can do to the MACs. Maybe we can all get it cheaper by then. : )
You know i have a MAC motor with the original white gears.. no suspension, i weigh 250lbs, i pump 1800 watts constant, 2300 peak into the motor regularly... those gears and clutch have not failed me.
I have the new wider and stronger gears for my MAC but they just sit in their box.
cell_man is upping the phase wires on the MAC motors he sells too.
But given that you can easily perform this upgrade yourself, i wouldn't call it much of a selling point for either motor.
So the only thing that the "BMC V4" has over the MAC is the increased amount of copper and "10% efficiency gain" ( pretty wild claim IMHO ) over the MAC motor. Hi-power cycles is known to make some far out claims.. ( and do things like sell you a 50 amp controller to run at 72v, which *will* kill these geared motors )
I have the new wider and stronger gears for my MAC but they just sit in their box.
cell_man is upping the phase wires on the MAC motors he sells too.
But given that you can easily perform this upgrade yourself, i wouldn't call it much of a selling point for either motor.
So the only thing that the "BMC V4" has over the MAC is the increased amount of copper and "10% efficiency gain" ( pretty wild claim IMHO ) over the MAC motor. Hi-power cycles is known to make some far out claims.. ( and do things like sell you a 50 amp controller to run at 72v, which *will* kill these geared motors )
Sacman
10 kW
Doesn't Noxie run BMC and Puma motors?
He would know where and how to get them in Europe.
He would know where and how to get them in Europe.
neptronix said:
oatnet
1 MW
neptronix said:
The folks like Maytag who were stripping gears in the early BMC's were putting a lot more power into them than that, but I agree these motors are up to the light duty like yours, which would meet the needs of 80% of the folks here.
neptronix said:
I get the sense that you are trying to pit the BMC against the MAC, which is sorta like comparing the base model Camero to the base model Firebird - they are two different companies take on the SAME design, the differences are nuances, not fundamentals. There is no reason that MAC can't introduce the same windings used on the BMC. They can probably develop gears with similar properties, maybe they already have, maybe their gears are stronger, I don't know.
Most BMC sellers (highpowercycles, betterybikes) have obnoxious markups; Ilia (ebikes_sf) is the only BMC vendor I know of with reasonable prices, I have bought a lot of product from him with good results. BMC has shipped motors with some grevious factory flaws, which is especially aggravating if you paid the high markup from somewhere else. cell_man has an angle on the MAC motors which makes them pretty cheap from him; I have also bought a bunch of product from cell_man with good results. Although both vendors are reliable, and both motors are similar, there are nuances that might lead a customer to one seller/motor or the other - basically you can't go wrong either way.
As for the V4 winding - in the end, I wasn't pleased with the V3. While the V2 works with about any controller, the newer-more-efficient-V3 was a controller-smoking pain for me, so a more efficient winding in the V4 doesn't excite me.
-JD
oatnet said:
I am trying to pit the two together. I fail to understand why the BMC costs so much more and a simple thing like a clutch + gear assembly runs over $100. That's stupid levels of markup, same as $5000 suspension forks and other bike bits.
MAC does have wider stronger gears just like the BMC V4; they introduced wider gears before BMC actually.
BTW, MAC motors are cheap even from vendors other than cell_man; it's just that cell_man has the lowest price on em, plus ships internationally. I have priced out some from a vendor in CA ( i forget, maybe it was lyen? ) And it was still nowhere near the BMC price.
Oh as to controllers, you left the game early. If you still have your motor you should try one of cell_man's new controllers. Very smooth and seem to handle these motors exceptionally well.
As for the V3.. well it's a fast speed winding.. it wants higher constant amps and low voltage, which is a recipe for controller failure. MAC has an equivalent wind ( 6T ) and experiences the same problems. Fact is, those motors just aren't that great for hitting higher speeds due to the hunger for amps. Far better to run a mid-low speed winding on a crapton of volts..
IMHO the real big problem was people selling BMCs seemed to be not so well informed about their limits or controller issues.
Yeah, go pump 50 amps x 72 volts into a V3.. i'll sell you replacement parts for a few hundred dollars when you're done melting every component inside
neptronix said:
I think the BMC have wider clutch. I don't know if their gears are wider, but definitely the clutch is wider. I think their was a post where ilia shows the difference and the new one does freewheel better.
All in all, I hope that MAC implements this type of clutch sometime in the near future. Wider is probably better for stability and reliability in the long run.
The BMC bearings are Japanese on my BMC V3. I don't own a MAC motor so I cannot say that their bearings are japanese.
neptronix said:
The rule is keeping the input power to something < 1500 and you should be good. So if you are running 72V, then all you can put into it is 20-maybe 25Amps at most. Otherwise you risk frying it.
Finally, I got a chance to test weatherproofness of the BMC V3 last week... And all I can tell you is it was great! The motor was getting wet on the outside, but it still worked for the 10 mile ride from school to home, taking on hills and puddle of water splendidly. I can't say the same for the MAC though. Maybe someone can confirm it for me.
Yeah i know about the power rules, i've taken the MAC to it's limits and back.
What i'm pointing out is that hi-power cycles is the same company that said here, pump 50a/72v into this motor and have a nice day.
http://www.hi-powercycles.com/product.sc?productId=104&categoryId=28
^-- that's right, they'll sell you a bike and tell you that the BMC will do 3500w.
Same company that threw the 10% better efficiency claim out there.
What i'm pointing out is that hi-power cycles is the same company that said here, pump 50a/72v into this motor and have a nice day.
http://www.hi-powercycles.com/product.sc?productId=104&categoryId=28
^-- that's right, they'll sell you a bike and tell you that the BMC will do 3500w.
Same company that threw the 10% better efficiency claim out there.
oatnet
1 MW
neptronix said:
I have not found the MAC at for sale from a US vendor, if you can supply the data point of an advertised price lower than ebikes-sf's BMC, you could change my opinion. Lacking that, it is my opinion that you aren't actually comparing motors, you are comparing a vendor in USA with a vendor in China. Here is the difference: cell_man has a hookup at MAC, he buys the motor at LOCAL CHINESE prices, not the prices for exporting to Rich Americans. If he had a hookup at BMC, he could get those motors for a similar price. Since cell_man ships directly to you, you dont have to pay the importing costs, customs fees, and markup by the importer/reseller who owns rights to sell the motor in the USA. Thanks to cell_man, you can bypass the expense of the whole retail chain - which probably accounts for a lot of the savings.
-JD
gensem
100 kW
oatnet said:
i think we shoulda thanks cell_man , bmc prices were much higher before... and i highly doubt ilia would be able to sell bmc at prices he does now if it wasnt the mac (even tho bmc replacements are still utterly hi).
Kris B Krunch
100 mW
Any updates or testing on the new v4 motors anybody? I have searched and found not too much on the topic.
Thanks!
Thanks!
Grizzlybear
100 W
I've just built a rear Mac motor up into a rim for a friend, and found the disc mounting surface to be throwing quite badly. It's not going to be a problem as he's using caliper brakes, but would definitely be a problem if he was using a disc brake. A few questions before purchase might be wise for potential buyers of Mac motors using disc brakes.
oatnet
1 MW
Grizzlybear said:
I can't think of a hub motor line where I haven't had this problem sometimes, I wouldn't put this at MAC's doorstep, it is more of a made-in-china issue.
-JD
I had that problem with the MAC motor too, but realized that rear v-brakes were powerful enough.
( note: i am 240lbs and frequently have to go down hills or make full 36-0mph stops in the city.. the front brake is an avid bb7 )
It also needed 2mm worth of spacers just to get the disc in the right place.
My regular bicycle wheel has this problem too.
So did my MXUS Geared motor.
The only hub motor that has good disc positioning that i know of is the MXUS DD motor.
( note: i am 240lbs and frequently have to go down hills or make full 36-0mph stops in the city.. the front brake is an avid bb7 )
It also needed 2mm worth of spacers just to get the disc in the right place.
My regular bicycle wheel has this problem too.
So did my MXUS Geared motor.
The only hub motor that has good disc positioning that i know of is the MXUS DD motor.
Kris B Krunch
100 mW
So, anyone out there with some testing on the new v4's? I'm still probably a month or two out from actualy buying my motor, currently on my honeymoon with some big bills to pay over the next while.
I was pretty much set on a v2t but I am currious about the new ones.
Thanks
I was pretty much set on a v2t but I am currious about the new ones.
Thanks
Grizzlybear
100 W
oatnet said:
The Bafang BPM is machined beautifully true. almost a work of art. I forgot to mention that the MAC/Puma's spoke holes are also all over the place, this makes truing the wheel more difficult, but it's still a great motor though, I've had 4 so far.
hi-powercycles
100 W
- Joined
- Jul 10, 2008
- Messages
- 105
We sell what we call our HPC Striker, HPC Thunderbolt, and HPC Black Lightning. This is based off of the BMC V4T, V4C, and V4S, but with a few internal changes and 8g equivalent outside the axle at half the length of standard V4 motors. I have been torture testing on a 25% hill for the last month or so using both standard BMC V4 motors and our custom versions as well, I burned out a bunch of motors in the process of finding out the maximum capabilities of these motors. This hill is so steep that most motors will stall on the hill at the steepest part. My intent is literally to break these motors as I pump as much current through them as possible. With the standard V4 motor and wiring (11g) the wires would literally burn my legs if I came in contact with them after one or two attempts at the 1/2 mile long monster hill. I will tell you one thing, so far, with the HPC Black Lightning I have not been able to kill it in about a month of abuse. I have been putting 50A continuous through it through the heaviest hills, and I have not been able to kill it, and believe me, I have tried. My guess is the V4S will be pretty good at handling the current as well. The V4S at 1100W is about 81% efficient compared to 68% efficiency of the old V3, so it is much improved.
If you are looking to get the V4 motors for the best price, I recommend Ilia at ebikes-sf whenever he gets them in stock. He is a stand up guy and his prices are quite frankly impossible to beat. The V4 motors should be trickling in to retailers in the near future. Of course, if you want our custom upgraded version of the V4 (HPC Striker, Thunderbolt, or Black Lightning), you can contact us, but know just the MSRP alone of the HPC motor is $100 extra.
If you are looking to get the V4 motors for the best price, I recommend Ilia at ebikes-sf whenever he gets them in stock. He is a stand up guy and his prices are quite frankly impossible to beat. The V4 motors should be trickling in to retailers in the near future. Of course, if you want our custom upgraded version of the V4 (HPC Striker, Thunderbolt, or Black Lightning), you can contact us, but know just the MSRP alone of the HPC motor is $100 extra.
Kris B Krunch
100 mW
Thanks for the reply Hi-Powercycles. Sounds like it could be quite a good motor
hi-powercycles
100 W
- Joined
- Jul 10, 2008
- Messages
- 105
Oh yeah, and another thing, I have killed the BMC V4C and BMC V4T on 50A, so don't expect to be pumping 50A continuous up the steepest grades. Most people will not torture the motors as hard as I do, but still 50A on heavy hills for prolonged periods is not recommended for the BMC V4 motors...
ebikerbythesea
1 µW
Kris B Krunch said:
Just bought a V4S with wheel build and 50A controller, will be arriving in a few days, so I'll post how it goes...
Kris B Krunch
100 mW
That sounds great. What did you do for a battery and how many watts do you plan to run it at?
ebikerbythesea
1 µW
Have an old 52V 10AH high current battery which should be good enough for now. And for the time being I'll be restricting the current to ~35A continuous (~1750W) via the current-limiting jumpers in the controller to help prevent the infamous BMC wire meltdowns. Hopefully they've also upgraded the wiring on this one. Supposedly the V4S (high speed version) should still be able to hit 40 mph on a 26" wheel at that power level. We'll see...Kris B Krunch said:
oatnet
1 MW
ebikerbythesea said:
"current limiting jumpers?"
Not familiar with those. Are you talking about cutting off some of the shunt leads? If so, have you considered the cycleanalyst throttle mod instead?
-JD
ebikerbythesea
1 µW
Yes, that's exactly what I meant, just didn't know the right word for them :? I agree, the cycle analyst throttle mod is a much better way to go, but all I've got for now is my humble Watts Up meter...will probably upgrade soon but for the time being, just being cheap!oatnet said:
