Please vete my build

[bronco9588]

I have the following requirements:

1) Get me to work in 1/2 hour (average 20 mph)
2) Get me to work and back (20 miles)
3) Use my current MTB: motobecane 700ds which has a 9 speed cassette 135mm drop
4) LiFePO4 chemistry for longevity

I was thinking of getting:
em3ev MAC kit with 8T: I have a flat commute and would like to get some high speeds out of the bike
ping battery 48volt 15 amp hour

Questions:
1) Will i meet my requirements with the items being purchased?
2) I was thinking of mounting the batteries in a book bag with some anderson quick disconnects. Is this a terrible idea? that way I could take the batteries into work.
3) What wheel should I get with the MAC kit? 19, 24, 32 mm? Is there any pros or cons here?
4) How does the throttle work on this kit? Is it 3 positions or is it a potentiality? How does the PAS work on this?

Thanks for your help!

 

[arkmundi]

Is that 20 miles one way, or round-trip?

 

[bronco9588]

That would be round trip.

I am looking at 1300 including shipping. I figure the cheapest bike I could buy in Hawaii is 1700. This should be wayyyyy more awesome for 400 cheaper.

 

[dogman dan]

Your plan will work very well IMO. At 25 mph cruise, you should have about 20-22 miles of range. You might have to go slower if you get headwinds on some days. If you can get any charge at all at work, then your range will be much better and you can haul ass both ways at top speed.

You might be getting a three speed switch, I'm not sure. The throttle is fully adjustable, 0-100% pick your speed with the throttle.

Screw PAS. your throttle hand is so much smarter than PAS. Set your speed, say 20 mph, then pedal up 2 mph more. Adjust throttle as you ride to keep your cadence and effort the same the entire ride. PAS can't do that unless it's very pricy.

Get the EM3ev triangle bag if it will fit your bike. A 48v 15 ah ping will fit in there.

Not sure what rim size you should choose. I'd pick the middle, it will work with a larger tire which I tend to prefer. Like a beach cruiser tire.

 

[arkmundi]

I was thinking of getting:
em3ev MAC kit with 8T: I have a flat commute and would like to get some high speeds out of the bike
ping battery 48volt 15 amp hour

Questions:
1) Will i meet my requirements with the items being purchased?

I believe so, since you clarified its 20 miles round trip. After an exhaustive comparison of kits & vendors, I went with the MAC 10T from EM3ev and am very happy with it. Keep in mind that a 15 amp-hour battery will just about cover you. You really don't want to over-charge or over-discharge a lithium-ion battery as it can damage the internal chemistry. I try to stay in the range of 80%<SOC<20%. Doing so will extend the life of your battery. The idea is to have excess capacity.

2) I was thinking of mounting the batteries in a book bag with some anderson quick disconnects. Is this a terrible idea? that way I could take the batteries into work.

Everyone getting a kit struggles with how to carry the battery and there are lots of options. There's the frame-bag which Dogman suggested. That puts the battery in the very center of gravity and equalizes the weight on the wheels. I put mine on a rear rack pannier style so as to maintain a low center of gravity. Yes, you can carry a battery as you suggest. Just keep in mind that batteries tend to be heavy and can shift around and throw you off balance. There are some who successfully carry a battery in a backpack. That solution straps the battery to your person so shifting is not a problem, but also puts the weight above the center of gravity.

The advantage of such an approach is that you carry your battery with you. At work or home, to recharge and remove the battery as a temptation for thievery. If you're planning on locking up your bike outside, then it can be a good idea to consider the practicalities of recharging and protection against theft.

3) What wheel should I get with the MAC kit? 19, 24, 32 mm? Is there any pros or cons here?

Get the Alexrims DX32 - its the very best rim Alexrims makes and EM3ev carries. The DM24 is also a great rim. The wider DX32 is great for wider tires, like the 2.5" Maxxis Hookworm tires I use. Also make sure to get the Sapim spokes for lacing the hub into the wheel.

4) How does the throttle work on this kit? Is it 3 positions or is it a potentiality? How does the PAS work on this?

There is a 3-speed switch and a throttle. The switch is a low-medium-high so you can change the effective range of the throttle. They work together. There's also a cruise control button. Like Dogman, I'd avoid PAS.

 

[bronco9588]

Unfortunately, the bike is not a hardtail coupled with a very poor frame design does not give me a lot of space.
http://www.motobecane.com/400_700ds/ I think with a a BMS, I shouldn't have to worry about some overheating issue, and I like keeping the bike light for transporting purposes.

So the throttle has "infinite" positions? Anyone have good experience with the thumb throttle or the twist throttles?

I feel like a wide tire is going to feel very heavy.

Anybody recommend getting the extra gears or clutch for the MAC? Spare parts?

 

[arkmundi]

Final Parts List: MAC 10T, OSN A123 48V on Trek Shift 3

 

[USAEBIKECO]

Bronco,

All of your requirements for an ebike can be met for under $1500. Message me if you need any help.

 

[dogman dan]

Ahh, yes no frame bag for that bike. So its a rear rack, the seatpost type. Add additional bracing to it, two bars from the middle of the rack back to the seatpost tube on the bike. Drill right through both the seatpost and the seatpost tube to bolt them on.

The box in this pic has a pingbattery, 48v 15 ah inside.

 

[scfoster]

Second the seatpost carrier.

Here's the Ibera PakRak carrier I've been using (rated for 22lb). Haven't needed any bracing (only used for street riding).