The MAC/GMAC will produce more torque per amp than any ebike motor assuming you feed the same battery amperage. That is one of the big advantages of a geared hub motor. I have been running 160 phase amps (55A battery amperage limit) and no issues with the gears or clutch :wink: .
Radwagon 72v GMAC Phaserunner Build
- Thread starter RSwannabe
- Start date
Tommy L
100 kW
Omg that’s near 4kw in a geared hub. Oh my!!!
Ok.... now I need to find a donor bike.
Maybe the NYX frame.
Ok.... now I need to find a donor bike.
Maybe the NYX frame.
Before you start your build....you can't run over about 1,200 watts continuously or the MAC will over heat.
You can push 60A with 58.8v temporarily without any problems. The MAC does put out more thrust/torque than any motor available for an ebike assuming you feed them both the same battery amperage.
Just didn't want anybody to think that you could continuously run high amperage through a geared hub motor....that would require a big Direct Drive Hub Motor like a QS205, Grin's DD45, or something similar.
You can push 60A with 58.8v temporarily without any problems. The MAC does put out more thrust/torque than any motor available for an ebike assuming you feed them both the same battery amperage.
Just didn't want anybody to think that you could continuously run high amperage through a geared hub motor....that would require a big Direct Drive Hub Motor like a QS205, Grin's DD45, or something similar.
The upper limit for current/power is defined by the temperature getting too hot
Just make sure the controller supports derating based on adjustable overtemp setpoint, ideally a smooth curve.
Then the watts/amps limitation will vary depending on speed, slope, weight, ambient temps, cooling design, even wind direction
Just make sure the controller supports derating based on adjustable overtemp setpoint, ideally a smooth curve.
Then the watts/amps limitation will vary depending on speed, slope, weight, ambient temps, cooling design, even wind direction
The amperage limit is defined by what the battery can supply, the controller can transmit and the motor can handle without breaking if you are only going to do it for a short period of time.
A MAC may be able to handle more than 60A at 58.8v for short periods of time, that is all my battery's BMS can handle.
There is some good data on the Grin Tech web site where Justin did experiments to determine the maximum "continuous" as well as a "Five Minute Limit" for the wattage a MAC/GMAC can handle without over heating...it is about 1,000w continuous and 2,600w for five minutes: https://www.ebikes.ca/product-info/gmac.html
Justin's data is for the motor to reach 110C...which is fairly conservative.
Justin and I both have run a MAC at 145C and 150C respectively for extended periods of time without any problems.
A MAC may be able to handle more than 60A at 58.8v for short periods of time, that is all my battery's BMS can handle.
There is some good data on the Grin Tech web site where Justin did experiments to determine the maximum "continuous" as well as a "Five Minute Limit" for the wattage a MAC/GMAC can handle without over heating...it is about 1,000w continuous and 2,600w for five minutes: https://www.ebikes.ca/product-info/gmac.html
Justin's data is for the motor to reach 110C...which is fairly conservative.
Justin and I both have run a MAC at 145C and 150C respectively for extended periods of time without any problems.
Just today I was riding my Radwagon and pushed it hard. I gave it full throttle (1500 watts with my current settings) up a steep hill (riding up W Dravus on the west side Queen Anne) for about 5 minutes and then cruising at 30mph plus and I only saw 75 degrees centigrade on the temp sensor. Lots of toque and high speeds and running strong. I love this setup!
RSwannabe...what diameter rear tire are you running?
Still running the Hookworms, if yes how do you like them?
I am running a 29x2.6" Maxxis Ikon right now and the large diameter makes my overall gearing a little too high for my conditions...which in turn contributes to overheating. Not terrible but I am on the edge of over heating when it is 95F outside and I ride for extended periods of time. I plan to go with a little smaller diameter tire when I wear out the Ikon. Either a 26"" Hookworm or a Schwalbe 26" or 27.5" Super Moto-X will probably be my next tire
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The advice I give to those trying to decide between a MAC/GMAC geared hub motor and a Direct Drive motor is that if you want to ride over about 30 mph for extended periods of time then a Direct Drive hub motor may be better for them. Between about 20-30 mph and a MAC/GMAC is the best motor IMO because it has more torque/thrust than a Direct Drive (assuming you supply the same amperage) and below about 20 mph a mid drive might work best.
Sounds like you hit the sweet spot for your set up and conditions...which is awesome :wink: .
Still running the Hookworms, if yes how do you like them?
I am running a 29x2.6" Maxxis Ikon right now and the large diameter makes my overall gearing a little too high for my conditions...which in turn contributes to overheating. Not terrible but I am on the edge of over heating when it is 95F outside and I ride for extended periods of time. I plan to go with a little smaller diameter tire when I wear out the Ikon. Either a 26"" Hookworm or a Schwalbe 26" or 27.5" Super Moto-X will probably be my next tire
.The advice I give to those trying to decide between a MAC/GMAC geared hub motor and a Direct Drive motor is that if you want to ride over about 30 mph for extended periods of time then a Direct Drive hub motor may be better for them. Between about 20-30 mph and a MAC/GMAC is the best motor IMO because it has more torque/thrust than a Direct Drive (assuming you supply the same amperage) and below about 20 mph a mid drive might work best.
Sounds like you hit the sweet spot for your set up and conditions...which is awesome :wink: .
fussler said:Hey guys
I just got my gmac installed with my phaserunner v2
Did you go with the 8T or the 10T...I like the 10T a little better personally but they are both good motors.
What voltage are you running?
The L10 connector sure is convenient but it won't carry as much amperage as the older bullet connectors that used to come on the MAC. It is perfect for the set up you have with the GMAC/Phaserunner.
I run a 52v battery with a 12T MAC and a 12 FET Infineon controller set to 50A battery and 140A phase current. Acceleration is terrific and it has a top speed of 27 mph on level ground with the 29x2.6" Maxxis Ikon...measured with a GPS.
I went with the T10 @52v
today after the first test drive but it cut out and i pushed the bike home.
Now it's dead.
Is it really necessary to change the cable when using the old MT-Phaserunner and the L-10 adapter..
or should i get a new phaserunner v3?
today after the first test drive but it cut out and i pushed the bike home.
Now it's dead.
Is it really necessary to change the cable when using the old MT-Phaserunner and the L-10 adapter..
or should i get a new phaserunner v3?
