# ME0708 vs ME0709



## BradQuick (May 10, 2008)

I have a 72V system using a Perm motor on mine. It makes a pretty nice setup. The Perm is closer to the ME0709. One problem with the lower torque motor is that you have to put a much larger rear sprocket on the bike, which in my opinion makes it look odd. With the ME0709, you should be able to use close to stock sized sprockets.

- Brad


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## frodus (Apr 12, 2008)

ME0708 is 315 pound inches. (26 ft pounds) 1.05 pound inches per amp
ME0709 is 525 pound inches. (43.7 ft lbs). 1.75 pound inches per amp.

If you want a bit more torque, get the RT.

The difference in volts/rpm isn't that much, I think you might be reading the torque curve wrong....

what are you referencing?


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## PartsMan (Aug 20, 2009)

frodus said:


> ME0708 is 315 pound inches. (26 ft pounds) 1.05 pound inches per amp
> ME0709 is 525 pound inches. (43.7 ft lbs). 1.75 pound inches per amp.
> 
> If you want a bit more torque, get the RT.
> ...


That sounds more like it. I can see paying the extra $ and having more batterys for that kind of gain.

This is what I was looking at. Maybe those figures are at 12v or something.


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## frodus (Apr 12, 2008)

those are all peak for a 48V system. Peak torque is 160 and likely at 150A, peak loaded RPM is 3200. Peak power is ~6000w. Not necessarily at the same time.

Look at the performance curves from Mars's website.
http://www.marselectricllc.com/peda.html

Look at 48V CW. the torque is on the bottom. RPM is in black. RPM is a little lower, but the torque is much higher. The 0709 is also more efficient.


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## Drew (Jul 26, 2009)

What do you want to do with the bike? If you're hoping for highway speeds then neither motor is probably going to cut it, I've done the calcs and estimated the power consumption of me on a motorbike at over 7kW at 100km/h. 

Small scooters use CVTs and have some pretty awful performance and top speeds in the range of 80-100km/h on the flat in favourable conditions, you might be able to adapt a CVT and then 6-7kW will be good to get you around town, but I'd avoid the highway.


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## Juiced (May 2, 2009)

The ME0709 will do Highway speeds just fine. (drag races well too) 

If you live in a relatively hot area (Southeast here and it is HOT) a motor fan or cool ducting would be advised. I just came back from Lowe's and a good chunk of the trip was on the highway. The Mars Rt motors latest edition (post April 2008) will work fine. 

100 Miles on the highway at highway speed....not with lead.


Sparky


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## PartsMan (Aug 20, 2009)

It still looks like to me that with the same amount of battery and gearing to match each motor they would perform the same. One pulls more amps and makes more RPM the other takes more volts and makes more torque at lower RPM.


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## PartsMan (Aug 20, 2009)

I compared the motors at 100a at 24 and 36 volt.
(Half the voltage and amperage I would be running them at but it was the only data I had)

0708 at 24v 0709 at 36v
110_______170 in lb
1600 ______1550 rpm
55_________56.67 in lb per 12v battery

The tiny difference could be geared out with the extra 50rpm the 0708 is makes.

I guess the 0709 would have an advantage if you compared both setups with the same weight vehicle,
but 6 Deep cycle batterys is going to require a much bigger bike than 4.


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## Juiced (May 2, 2009)

We can look at it this from a different perspective. The future.

The motors, for the most part, are only about 50$ US difference in price.

The ME0709 will give you the potential of running 72 volts in the future. Well worth the little bit of extra few bucks. Run the 48 volts now....have more fun later with the same motor. 

And buy it from a dealer....NOT Ebay. (and I like Ebay) 

Mars LCC is in CA. Cloud Electric in GA. 

Enjoy!!!!


Ed


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## PartsMan (Aug 20, 2009)

Juiced said:


> We can look at it this from a different perspective. The future.
> 
> The motors, for the most part, are only about 50$ US difference in price.
> 
> ...


But I would be paying $50 more to give up 1000rpm.


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## PartsMan (Aug 20, 2009)

Ah Ha. I got.
I was forgeting one important little detail.
ME!

Even with a 100lb heavier bike and 100lbs more battery the bigger motor would have less weight per in lb of torque after you ad another 220lbs of dead weight.


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## gregski (Sep 6, 2011)

frodus said:


> Look at the performance curves from Mars's website.
> http://www.marselectricllc.com/peda.html


This was a good discussion, but the link is broken, I guess since they changed company names.


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## Juiced (May 2, 2009)

Here is the new link! 

http://www.motenergy.com/brdcmo.html


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