Mac 6t compared to the q100 328

[Stumbc]

Hello!

So I have a question about my next purchase. I have a 328 q100 in a 700c wheel at 36v, 14.5amps. I know that this is a very low torque system but I quite enjoy the smooth acceleration. I was wondering if someone could tell me if the mac 6t at 30amps 36v in 700c wheel would give me the same/more torque than the q100.

 

[The Stig]

On average it should give you close to double the torque at double the current. I wouldnt go with a 6t though maybe 8t or 10t. Try figuring out how to use and read the ebikes.ca simulator(google that) and then use the search box in the top right corner of this site(always tick "using google search?) to find a relevant thread which may help you use it or post questions there or in this thread

 

[DAND214]

I don't think a 6t would like the 700c size. i'm suprised the Q100 is still alive.

I would do a 8 or 10t in the 700 wheel and it will feel great.

I had 3 Q128 early version motors, they were great in a 26" on 48v for a long time. Some how I stripped the gears doing off road. tried the newer version and they were crap, so now I have 3 MACS. Along with other geared and DD hubs. I like the feel of the MAC 8t on 44v or 12s LiPo. I still see 33mph + on just 44v and best I got on 15s or 57v was just short of 40.

I think you would like the MAC 8t with the 36v you have.

Dan

 

[amigafan2003]

How noisy ar the MAC's?

I'm considering changing my q100 for one as I'm hankering after more power.

It's between the Bafang BPM and Mac atm.

 

[chas58]

You staying at 36volts? I have a Q100 328rpm on a 700c wheel. Its pretty fast, but it is more bicycle than motor scooter.

328rpm is not fast enough for ya, so you want a 400rpm motor? That is going to be over 30mph on a 700c wheel (more like 35mph on a full battery).

Doubling the amps is going to give you a big increase in torque.

 

[dogman dan]

Definitely more torque with more amps, but using such a high speed wind on a big wheel will make more heat from some of those amps. So if efficiency is of no interest whatsoever, go with the 6t. It will still take off a bit sluggish because of the fast wind combined with big wheel. Sure you amps doubles, but your wasted amps might quadruple.

Another thing to consider, can your current battery hack 30 amps? If not, you are buying new everything. If so, run that mac on 48v so you get some speed from a slower wind. Then you get more torque, nicer starts, and still go fast enough.

If you ask me, the 6t and the 328 are for smaller diameter wheels.

 

[Stumbc]

Yea, I'll be staying with 36v since i have a 30ah lifepo4. My route has a 9 mile stretch of road once i get out of the city and i love the way the 328 cruises. I would just like to cruise a little faster. It looks like people here steer more towards the 8t, but some of those people are that same type who wouldn't use the 328 in a 700c. hmmm. It looks like once I get up to operating speeds (20-25mph) the efficiency isn't as bad as far as cell-mans diagrams.

 

[chas58]

True, lots of people say "never use a 328 in a 700c", but it actually is a nice combination if you keep it in its sweet spot. 15-25mph That is going to keep you in the 70-80% efficiency range which is perfect for that motor. Just don't go climb hills with it at <10mph.

You can see this all in the simulator:
http://www.ebikes.ca/simulator/


I'm really not sure why people are happy riding at X speed on 48v and then say don't try to ride that same speed on 36v (using a faster wind motor). Yeah the 48V motor will have more power (if that is what you want/need), but if you are riding in the motor's efficiency range and don't need the extra power, why not stay with 36v and use a higher speed wind? That is why I got the 328rpm motor (Q100).

Just realize your setup's limitations - you can not spend a lot of time at full throttle and low speed without burning something out.

 

[dogman dan]

True, with 9 non stop miles part of your route, then you would get a nice cruise out of the fast motor. Without any need to up the voltage. A fast winding motor is a joy on a long, relatively flat run.

But since you were asking for more torque, turning much of that extra amps into heat with a fast motor on starts will lose you some of that potential torque.

To be clear, the slower motors do not have more potential torque. But they get going quicker, reach the efficient rpm quicker, and it feels like more torque.

Bottom line, adding amps will improve your starts and hill climbs regardless of motor winding.

But when you want your cake and eat it too, a slower winding at 72v is the bomb.

 

[RLD70]

I concur with dogman as I have the 10T motor and go 27 mph on my 48v lifepo4 pack and the torque of this motor is the bomb so I can imagine what itll be like at 72v

 

[Stumbc]

what would a 6t at 72v be like? Just curious.

 

[The Stig]

That would be an intersting one to plug into the ebikes.ca simulator. It has similar motors like BMC V2-S

 

[Stumbc]

I thought the bmc v2 spd was more like the 8t

 

[The Stig]

yeah so by comparing the v2-t to the v2-s you can extrapolate/imagine what a 6t is like, or you can compensate with voltage.

 

[dogman dan]

I shouldn't have mentioned 72v. I do that with direct drive motors that shed a bit of excess heat faster.

10t at 48v is a proven winner. In your case, wanting good cruise speed, an 8 t should work ok at 36v. 6t, faster of course, but you won't have as much zip leaving stop signs.

 

[neptronix]

I concur with dogman as I have the 10T motor and go 27 mph on my 48v lifepo4 pack and the torque of this motor is the bomb so I can imagine what itll be like at 72v

It may do about 40, but it can't hold that speed for tooo long. Remember that these are 1000W continuous motors. 40mph takes 2000-2500W continuous to cruise at.

I nearly blew out my 8T running 72V on it. Hit a max speed of 46 or so. 2 days later, the gears chipped apart. Must have softened them up from all the heat, lol...

[youtube]UD_K_TRGcs4[/youtube]

So there. Now you know the limit of the MAC I've had that motor for almost 3 years. Still a reliable 25-35mph rig after all the wanton abuse i put it through many times.

 

[RLD70]

Originally I purchased the upgraded 6T rear motor from em3ev and Paul kindly warned me about using the 6T on a 26" wheel and about using more than 48v on it. He basically told me that if a higher voltage was going to be used with it then itd be wiser to pick a different winding because the motor is hard on the controller as is and that its not really made for those sized wheels either. So I chose the 10T over both the 6T and the 8T and Im glad I did as I now finally have my hauling bike not to mention the acceleration it has from a dead stop

 

[GSteg]

I initially wanted to get the Q100 328 but the price difference was small enough for me to opt for the Mac 8T. I'm glad I did because it seems to be more robust than the Q100. I wanted the 10T because of torque (12T would be too slow), but because of my 39v battery, I didn't think I would have enough speed so I went with the 8T. To my surprise, it had more torque than I anticipated, and it gets me over hills without pedaling. If I lived in a hilly area, I would probably get the 10T instead.

 

[chas58]

good feedback here.

I'm still not sure what the difference would be between a 8t at 36v and a 10t at 48 volts, other than the 48 volt motor would obviously have more power (at the same current). They both are going to be doing about 320-330 rpm.

 

[The Stig]

... the difference would be between a 8t at 36v and a 10t at 48 volts...

There should be almost no difference, if both are running at the same over all power (watts). The only difference will be that the 48V is slightly more efficient and produces slightly less heat in the phase wires, between the controller to the motor windings(some of that heat transfers its self to the windings/less heat transfers itself away from the windings down the phase wires). Because the 10t can get the same torque with less "phase current"

 

[chas58]

Thanks!

I think for now I'll stick with 36v to limit power usage and allow me to use smaller lighter batteries (10s vs 13s)