bafang 750 watt hub motor

Timpo

Well-Known Member
is grin's gmac hub more powerful than their ezee hub or more efficient (running on 48 volts)
Yes.

HillEater used to offer eZee option for more budget conscious customers, but I believe everyone just went for GMAC with small price increment. HillEater isn't exactly a cheap bike, so if you're spending good amount of money, it didn't make sense to compromise the motor to save small amount of money.

HillEater used to post performance difference between GMAC and eZee, and yes, GMAC was superior in every aspect except the price was a little bit higher.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
is grin's gmac hub more powerful than their ezee hub or more efficient (running on 48 volts)
Grin's motor simulator spreadsheet is an absolutely fabulous tool for answering questions like this, or even playing "what if" with any other ideas. It's incredibly accurate when predicting anything you would want to know. Take some time and play with it/get to know it. Plug some stuff in and hit "simulate", and poof, there's your answer-

As can be seen in the link, the motors you are thinking of are virtually identical, all else being the same -
 

cmugler

Member
Region
USA
so with the GMAC does the regenerative breaking function like on an electric car where when going down a long steep hill you may still need to apply throttle to maintain sufficient speed but the battery is still receiving juice
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
so with the GMAC does the regenerative breaking function like on an electric car where when going down a long steep hill you may still need to apply throttle to maintain sufficient speed but the battery is still receiving juice
The GMAC, when set up as directed, has "variable" regen that works much like your throttle in reverse. My understanding is it's plenty capable of locking up the rear wheel, even at speeds of less than 10mph. It's the combination of the hardware AND software that makes it a game changer.
 

tomjasz

Well-Known Member
GMAC was superior in every aspect except
Different, not superior. EeZee are very well made and a top notch GD hub. Every rider will not put the GMAC to its best use. The
TDCM IGH Kit is another great design. All have their place. My eezee build was a pleasantly pleasing build. Top tier quality and reliability. Only a BMC might exceed the build quality.
 

Timpo

Well-Known Member
Different, not superior. EeZee are very well made and a top notch GD hub. Every rider will not put the GMAC to its best use. The
TDCM IGH Kit is another great design. All have their place. My eezee build was a pleasantly pleasing build. Top tier quality and reliability. Only a BMC might exceed the build quality.
Care to elaborate?

When I saw the HillEater's spec, GMAC was better than eZee in every aspect, more power, more torque, more top speed, everything.

Except the price, as I said.
 

tomjasz

Well-Known Member
GMAC was better than eZee in every aspect, more power, more torque, more top speed, everything.
Everything? And everyone needs more power, torque, speed, and everything?
Goofy.
But I guess URL warriors know more...

This is where I take umbrage. Supercilious claims of what constitutes better. Sadly I like them all...well mostly.
 

Timpo

Well-Known Member
Everything? And everyone needs more power, torque, speed, and everything?
Goofy.
But I guess URL warriors know more...

This is where I take umbrage. Supercilious claims of what constitutes better. Sadly I like them all...well mostly.
Okay I was referring to the specs that I saw.
I did say everything except the price. Which indicated that eZee has its own value.
If there's anything else, you're more than welcome to post.

You have propensity to cut part of the sentence of posts, and sometimes that's annoying because I have to make corrections.
As you know, that already happened.

Your post didn't mention anything to point out the corrected facts, rather than calling me goofy. 😐
Please post corrections. What's eZee better at? torque? rev?

As I said, I was referring to the spec comparison I saw.
Please make corrections, if there's something else eZee is better at, I'm sure cmugler would appreciate it too.
 
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cmugler

Member
Region
USA
OK I am ordering a GMAC from grinn technology, on their rim options it lists "rim 275_Alex" am I to assume that is a 27.5 rim and they forgot the period between the 7 and 5 or is that another size rim, also will a 2.8 wide tire fit on a 32mm wide rim or should I go with a 2.6"? thanks
 

Timpo

Well-Known Member
OK I am ordering a GMAC from grinn technology, on their rim options it lists "rim 275_Alex" am I to assume that is a 27.5 rim and they forgot the period between the 7 and 5 or is that another size rim, also will a 2.8 wide tire fit on a 32mm wide rim or should I go with a 2.6"? thanks
Awesome!!
Which T (turn) are you getting?
 

cmugler

Member
Region
USA
likely the 10T would that be best for primarily road use, 27.5 wheel, 52 v battery , some trails, total weight with bike 220 pounds? Also which pedal sensor is recomended want it to be as smooth as posible
 

Timpo

Well-Known Member
OK I am ordering a GMAC from grinn technology, on their rim options it lists "rim 275_Alex" am I to assume that is a 27.5 rim and they forgot the period between the 7 and 5 or is that another size rim, also will a 2.8 wide tire fit on a 32mm wide rim or should I go with a 2.6"? thanks


You'll be fine.
Here's the chart: https://www.lightbicycle.com/newsletter/tire-size-chart-for-bicycle-rim.html 😁

Internal rim width (mm)1920212223242526272829303132333435404550
Tire size 1.9"√√√√√
Tire size 2.0"√√√√√√
Tire size 2.1"√√√√√√√√√√
Tire size 2.2"√√√√√√√√√√√
Tire size 2.3"√√√√√√√√√√√√√
Tire size 2.4"√√√√√√√√√√√√
Tire size 2.5 - 2.7"√√√√√√√√√√√
Tire size 2.8 - 3.1" (Plus)√√√√√√√√
Note:
The recommendations are based on our rim-tire compatibility tests with some of the most popular tires. This chart only serves as a general guide since bead design, inflation pressures, and other variables will affect the actual rim-tire compatibility. Please send the rim profile to the tire manufacturer to double-check.
We don’t suggest choosing the largest or smallest values of a size range. For example, with a range from 1.9” to 2.1”, 2.0” is an optimal option for most riders.
The chart is only applicable to Light Bicycle rims with a unique rim-tire interface. If you use rims of other brands, please send a rim profile to the tire maker for recommendations.
 

Timpo

Well-Known Member
likely the 10T would that be best for primarily road use, 27.5 wheel, 52 v battery , some trails, total weight with bike 220 pounds? Also which pedal sensor is recomended want it to be as smooth as posible
I don't have personal experience with it, so I can't tell you how good they are, but Sempu sensor is what HillEater use.
I personally like cadence sensor, but I know a lot of people prefer torque sensor.

Grin sells it as well.

 

tomjasz

Well-Known Member
likely the 10T would that be best for primarily road use, 27.5 wheel, 52 v battery , some trails, total weight with bike 220 pounds? Also which pedal sensor is recomended want it to be as smooth as posible
The version best suited to your build. All Grin versions are great. OR Grin does sell BB torque sensors.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
OK I am ordering a GMAC from grinn technology, on their rim options it lists "rim 275_Alex" am I to assume that is a 27.5 rim and they forgot the period between the 7 and 5 or is that another size rim, also will a 2.8 wide tire fit on a 32mm wide rim or should I go with a 2.6"? thanks
This is going to come down to 'druthers. I just switched my 26" bike (the one with the MAC 12t) to Schwalbe Moto-X 26x2.4's. Love them, and I know they're available as a 27.5x2.4". That's as small as I would go with a 27.5.

My point is, that rim is pretty skinny when talking tires that wide, and may limit options further down the road. I would look for a rim where the INSIDE dimension is 32mm or bigger (even 36-40mm?). That's me though..... -Al