Newbue wants to build an ebike

[johnjapan]

hello everyone this is my first post here and I'd like to introduce myself before I post my question

my name is John and I actually live abroad in Japan
I need to build an electric bike to commute everyday and would like to build something on my own

I want to convert a mountain bike I already have with these things in mind

1. I'd like a bike that will give me the maximum range possible, speed or power is not really a priority
2. I'd like the batteries to be removable so that I can bring them inside to charge
3. I have a budget of about 1000 to 1500 dollars

I've done some research online and I've considered purchasing manuals on how to build a bike step by step but I signed up the forms have the most up to date information as to how to build

how do I get started ?

should I start with the batteries and if soshould I make custom batteries using little cells or should I just purchase batteries from China already packaged

 

[bowlofsalad]

The first thing I recommend doing is doing some research on various chemistries. For any newbie, I'd recommend lifepo4 or a123 packs. As for where to source them, that is a question that holds a lot of variable. There aren't many highly recommended vendors. It usually comes down to pingbattery.com or em3ev.com.

For range you probably will consider two primary attributes, pack size and your speed. The faster you go, the more power you will consume as you get there.

http://ebike.ca/simulator/ < Spend some time playing with this.

Watt hours is a key detail in figuring how far you will go. To find watt hours, multiply volts by amps. For example, a 36v20ah pack will have 720 watt hours. Lets say you consume 20 watthours per mile on your mountain bike at whatever speed. You will theoretically go 36 miles with that pack. Same story, different pack, 48v20ah will have 960 watthours, in theory you will go 48 miles with said pack.

Aerodynamics, weight, and rolling resistence all play substantial roles in how far you will go with a specific amount of energy.

As far as ebike kits for things like motors, controllers and such, yescomusa.com, em3ev.com, and ebikes.ca all seem to be reputable sellers.

There are plenty of sellers for ebike parts on places like ebay, it's cheap, but some say you get what you pay for.

 

[johnjapan]

Thankyou for the response bowl of salad, it was quite helpful.

The e-bike simulator is an excellent tool but unfortunately I am not familiar with terms used for the motors and the various models Ill have to do some google searching as to what the different fields mean.

The vendors you mention seem great but I fear that ill be paying an arm and a leg for shipping to japan.

Im going to concentrate on the watt hours I need something that can give me at least a 100km range

60v30ah should do the trick or a 72v25ah

Those batteries seem very expensive in the 1000 dollar range.

Isnt there a cheaper option to get more wattage ? Perhaps build a battery using multiple cells ?

 

[millzy555]

You play you pay sadly... To get 100miles is massive!!! and you will require a decent charging setup. Batteries + charger will eat a fair chunk of the budget, still have motor, controller, CA if needed and a bike of course. You may need to re-assess your requirements

 

[johnjapan]

no no no 100KM thats like 60 miles in USA ?

Im canadian we measure in KM so does Japan so I need a range of 60 miles

From what Im searching on the internet it seems cheaper to go with a123 cells
How do I know how many cells I need to achieve 72v30ah if each cell is 3.6v 1200mah ?

 

[millzy555]

Even so, 100km is still a fair wack, but can be done if you use the throttle lightly/ pedal alot (kinda defeats the purpose of an ebike)

20 cells = 72 odd volts, but its the amp/hr you're interested in, what AH rating are they? If you're going 20-30ah its still a heap of cells
Take lipo for eg: 6 x 6s packs of 5000 paralleled is 10AH, cost is around $60 per brick so 18 (to get 30ah) will set u back $1000 plus wiring harness plus charger!

 

[bowlofsalad]

no no no 100KM thats like 60 miles in USA ?

Im canadian we measure in KM so does Japan so I need a range of 60 miles

From what Im searching on the internet it seems cheaper to go with a123 cells
How do I know how many cells I need to achieve 72v30ah if each cell is 3.6v 1200mah ?

Are you certain you want 72v? Find a cells nominal voltage and divide by your goal. A123 typically has a nominal voltage of 3.3v. The reason a 72v or 48v or whatever v pack is called that is because that is typically the voltage the battery's capacity ends. I think a 72v pack is 24 cells typically. Although this information is really only important if you plan on building a pack, the way it works is you make a collection of 24s packs to make up the desired amp hours or 'ah'. So if you are dealing with a cell that is 3.3v nominal with 1200mah or 1.2ah per cell, you would need 24s25p or 25 packs of 24cell or 600 cells.

Anyway, em3ev.com ships from china. You'll need a pretty hefty amount of watthours to go 60 miles. The truth is, if you want to be certain you'll go 60 miles, you'll need to aim for more than just 60 miles. There are plenty of variables that go into how far a charge will carry you. Stops, weather, how much or little you pedal and so on. A 48v40ah or a 1920 watt hour pack might take you that far.

How fast do you plan on riding for the most part?

 

[DAND214]

Get all you need from Paul (cell_man) http://www.em3ev.com/store/He has all you are asking for.He has a great reputation here and has ben very honest with his products. If you don't see what you want be sure to ask him.

60 miles is a good size battery. If you plan on doing much more tha 20mph, speed kills as they say. people and batteries.

Dan

 

[e-beach]

.......should I start with the batteries and if soshould I make custom batteries using little cells or should I just purchase batteries from China already packaged

Depends on how good you are with tools, electronics and such.

Your most cost effective shipping is probably from China. Cellman aka Paul.

I can get 20+ miles from my 15ah Headway pack under normal city riding. I can get 40 miles from it if I go 6mph the whole way. No peddling either way. Of Course it will take me almost 7 hours to go 40 miles but that is the trade off for going very slow to get distance.

If you want to go 60 miles on a single charge you will need a very large battery pack.

So the question becomes, why do you need to go that far on a single charge?

 

[John in CR]

Check the laws and what's available locally, especially batteries. I was under the impression that Japan had really oppressive ebike regs and that they enforce them. It's one of the few places in the world that I wouldn't have my high power ebike.

 

[johnjapan]

All very useful responses

I want 60 miles for road trips but now I have to be realistic

40miles is fine with an AVG 20MPH speed

id like to make a custom battery pack so I can fit as many cells in my frame space as possible
but I think buying a battery kit is much faster


im going to check that paul China website

 

[Chalo]

Have you ridden 100 klicks at a stretch on any kind of bicycle? It's not for everyone, even if your bike does the pedaling.

If you're not game for a 30 mile ride by pedal power alone, you'll probably find a 60 mile ride by e-bike tedious and uncomfortable.

 

[johnjapan]

My surroundings motivate me to go further. I can handle 100clicks if
if the weather is nice and im surrounded by nature.


ive decided purchase this battery pack from japan



http://www.amazon.co.jp/gp/aw/d/B007RVOOWU/ref=mp_s_a_1?qid=1362745895&sr=8-6&pi=SL75


36v35ah should do the trick only 700bucks plus shipping maybe 750

 

[bowlofsalad]

My surroundings motivate me to go further. I can handle 100clicks if
if the weather is nice and im surrounded by nature.


ive decided purchase this battery pack from japan



http://www.amazon.co.jp/gp/aw/d/B007RVOOWU/ref=mp_s_a_1?qid=1362745895&sr=8-6&pi=SL75


36v35ah should do the trick only 700bucks plus shipping maybe 750

I'd be really surprised if you went 60miles at 20mph. Let's err on the safe side and guess you'll have an average power consumption of 25wh/m (watt hours per mile). This is assuming you will do little to no pedaling. 1260wh are in that pack, but you'll likely get around 1000wh out of it. That's about 40 miles. If you pedal lots, you'll likely meet your goal. However, you'd be a bit safer with a 48v40ah pack. The voltage says a lot about how fast you can go, but the watt hours are the number you are interested in concerning traveling distance.

 

[e-beach]

Based on my own experience I see it going like this.

My bike and I roll around at just under 300lbs. (136 kilos). I can get about 20-22 miles on my 15ah pack, with stop lights and all about 12 mph average, stop and go, not much peddling, not many hills, or about 1.4 miles per Ah.......so a 35ah pack would get me around 49 miles per charge (78 kilometers) depending on ridding conditions.

So 80 kilometers is possible with not much pedaling if you ride slow enough. And it may not be all that slow, 15 to 18 mph. (24-30 kph) depending on you riding conditions.

The bigger issue I am beginning to see with you is where are you going to put that big battery? If you put it on your rear rack, the bike will be unstable due to the weight.

 

[bowlofsalad]

Based on my own experience I see it going like this.

My bike and I roll around at just under 300lbs. (136 kilos). I can get about 20-22 miles on my 15ah pack, with stop lights and all about 12 mph average, stop and go, not much peddling, not many hills, or about 1.4 miles per Ah.......so a 35ah pack would get me around 49 miles per charge (78 kilometers) depending on ridding conditions.

So 80 kilometers is possible with not much pedaling if you ride slow enough. And it may not be all that slow, 15 to 18 mph. (24-30 kph) depending on you riding conditions.

The bigger issue I am beginning to see with you is where are you going to put that big battery? If you put it on your rear rack, the bike will be unstable due to the weight.

12mph vs 20mph is pretty substantial concerning power consumption. You didn't mention the voltage you have with your pack, that would be useful.

 

[e-beach]

12mph vs 20mph is pretty substantial concerning power consumption. You didn't mention the voltage you have with your pack, that would be useful.

"it is in my signature" he whispered. :lol: I don't always read that stuff all the time either.

36v 800w, but I don't go along at 12mph continuously, that is 12mph average in stop and go traffic. If I went 12mph continuously without the stop and go, on the flats around here, I probably could stretch another 2 - 4 miles out of my pack. However you are right about the substantial watt consumption difference between 12 mph and 20 mph. 80 kilometers on a 35 Ah pack at 32 kph (20mph) sounds a bit dubious to me unless there is a lot of peddling going on.

 

[amberwolf]

how do I get started ?

should I start with the batteries

http://www.endless-sphere.com/w/index.php/Picking_out_a_battery:_what_you_need_to_know

The e-bike simulator is an excellent tool but unfortunately I am not familiar with terms used for the motors and the various models Ill have to do some google searching as to what the different fields mean.

http://www.endless-sphere.com/w/index.php/Terminology_and_Explanations_of_Common_Misconceptions
http://www.endless-sphere.com/w/index.php/Terminology
http://www.endless-sphere.com/w/index.php/Acronyms
among others, and the ebikes.ca simulator page itself explains some of the terms.

Perhaps build a battery using multiple cells ?

http://www.endless-sphere.com/w/index.php/Laptop_LiCo_Cells
among others

 

[borschelrh]

John, Good luck to you and welcome to ES. I recently finished converting my mountain bike. I am using a 36v 9C DD hub motor kit with a Pedelec type LiMn aluminum encased battery pack with integrated BMS rated at 36v/10.5 Ah. I ride primarily off road and wanted assist for the hills. The particular kit I purchased meets all of my needs. I pedal constantly at my normal training cadence and slightly less effort than my normal ride. Given the additional weight the motor and battery add the assitance is making up the difference. I haven't yet ridden the battery to exhaustion so can't state the actual range. I also get regen from going downhill so it is really hard to say what I can get out of it. What I do see is that after a 32 km hard ride I only used 1/4 of the battery based on the integral battery gauge and the LCD panel on the motor kit. I believe I can get 100 km from the battery but again I am providing at least 75% of the effort. But, my effort is not tiresome and I am riding now at a constant 30 kph except going up steep hills and it reduces to me climbing in my granny gear and the motor putting out maximum effort (35% grade). I don't think my motor will pull me along without me pedaling. At least I don't seem to have found a setting on it for that, but for me that is fine. I like pedaling, want to pedal, need to exercise, and to lose weight so this is perfect for me.

I think the main decision you have to make early is if you want to pedal or not. My suggestion is that if you don't want to pedal then just buy an electric motor scooter. They are easy to find on TaoBao and are a less expensive than kludging a ebike conversion. But, if you want o cycle for exercise as well as transportation then something like what I did would work well. If you want a blasting trail cycle then either a custom frame bike specifically designed to be an off road ebike running at maximum volts and high powers using a mid-mount drive would be the best solution. There are various solutions in between. There seems to be several schools of thought and a lot of the members are shooting for high performance bikes. I can see the attraction now that I have ridden mine off road. But, for distance I think a DD hub kit would work best. I found my battery packs off ebay in Germany and they are working fine so far. I have 2 of them thinking I would need the extra amp hours but so far I haven't. I am building a trailer to haul my inflatable catamaran to the lake here and I tam thinking to mount the second battery on the trailer and wire it in parallel. I built the wiring harness today. The trailer will be next week. The trail to/from the lake is more or less flat but where I go sailing is about 15 km away and about 1/3 of it is dirt roads. This has been a interesting project so far and I am overjoyed at how well it is working for me.

 

[johnjapan]

John, Good luck to you and welcome to ES. I recently finished converting my mountain bike. I am using a 36v 9C DD hub motor kit with a Pedelec type LiMn aluminum encased battery pack with integrated BMS rated at 36v/10.5 Ah. I ride primarily off road and wanted assist for the hills. The particular kit I purchased meets all of my needs. I pedal constantly at my normal training cadence and slightly less effort than my normal ride. Given the additional weight the motor and battery add the assitance is making up the difference. I haven't yet ridden the battery to exhaustion so can't state the actual range. I also get regen from going downhill so it is really hard to say what I can get out of it. What I do see is that after a 32 km hard ride I only used 1/4 of the battery based on the integral battery gauge and the LCD panel on the motor kit. I believe I can get 100 km from the battery but again I am providing at least 75% of the effort. But, my effort is not tiresome and I am riding now at a constant 30 kph except going up steep hills and it reduces to me climbing in my granny gear and the motor putting out maximum effort (35% grade). I don't think my motor will pull me along without me pedaling. At least I don't seem to have found a setting on it for that, but for me that is fine. I like pedaling, want to pedal, need to exercise, and to lose weight so this is perfect for me.

I think the main decision you have to make early is if you want to pedal or not. My suggestion is that if you don't want to pedal then just buy an electric motor scooter. They are easy to find on TaoBao and are a less expensive than kludging a ebike conversion. But, if you want o cycle for exercise as well as transportation then something like what I did would work well. If you want a blasting trail cycle then either a custom frame bike specifically designed to be an off road ebike running at maximum volts and high powers using a mid-mount drive would be the best solution. There are various solutions in between. There seems to be several schools of thought and a lot of the members are shooting for high performance bikes. I can see the attraction now that I have ridden mine off road. But, for distance I think a DD hub kit would work best. I found my battery packs off ebay in Germany and they are working fine so far. I have 2 of them thinking I would need the extra amp hours but so far I haven't. I am building a trailer to haul my inflatable catamaran to the lake here and I tam thinking to mount the second battery on the trailer and wire it in parallel. I built the wiring harness today. The trailer will be next week. The trail to/from the lake is more or less flat but where I go sailing is about 15 km away and about 1/3 of it is dirt roads. This has been a interesting project so far and I am overjoyed at how well it is working for me.

I

I think the setup you have is perfect for me as well, infact it would feel too weird not pedaling.
I would like the power available to me though so if I feel like cruising back home the last stretch I can go 40 to 45kph

I love the regen setup you have there for downhill I might need your technical know how later for that one.
I found a battery supplier from within Japan that's charging 6 dollars per battery which is about the best deal in I'm going to get around here.


I will build my own battery pack from scratch using 18650 3.6v 2200mah cell batteries
Currently researching how to do so very overwhelming info right now almost want to buy a full ready kit lol cant giveup

 

[borschelrh]

John, I can't take credit for what the kit has included. The kit I bought is this one: http://www.ev-power.eu/EVBike-Kits-1-1/E-bike-conversion-kit-EVBike-36V-500W-Front-28.html It is a 9C kit so I am pretty sure you can find it in China on TaoBao or from one of the other sites like: http://em3ev.com/store/index.php?route=product/category&path=36 whose 500W kit looks almost the same. They are in your neck of the woods so I would look carefully at them. My motor is wound 7x9 so works for me but there is no way to go faster than 35 kph unless you are doing all the pedaling as it won't provide assist above the set speed. I was also going to build a battery pack but lost out on a bid for A123 soft packs in Germany and again on the Pedelec batteries. However, I wrote the seller of the batteries directly. The A123 got greedy so I rejected his offer but the Prophete/Triton batteries (common here in Europe for ebikes sold by Aldi, etc.) which are identical to these: http://www.amazon.de/dp/B0071IUP1S/ref=asc_df_B0071IUP1S12241131?smid=A352OILT3WCZVG&tag=sportskelkoode-21&linkCode=asn&creative=22506&creativeASIN=B0071IUP1S but I got 2 for only 164 Euros (used). I dismantled them and checked the balance and they are fine. I rewired/soldered the plugs on both the power cable and the batteries to use LiPo XT-60 connectors and 2.5mm wire. For me it all works fine and now I have an extra battery which I will mount to the trailer to make up for the extra weight I am asking the motor to pull. I have been unable to find a mounting plate for the battery so ended up fastening it to the tube with screw adjustable pipe straps. I recharge it on the bike and the BMS seems to work fine although some members on this forum hate these integral BMS that come on these batteries. I also was deliberately looking for LiMn cells not LiFePO4 as I believe the risk of fire is less. If you were into off roading without pedaling then I think HK Lipos would be better as they have 30C or higher discharge rates. I see mine is around 10C and I see power lag when climbing steep hills after 5 minutes or so but they keep hanging in there and haven't tanked yet. I can see on the "fuel gauge" display on the LCD panel that the charge drops to zero when it bottoms out. If I stop and wait 30 seconds it recovers completely. I am asking a lot from the system on these really steep grades. They are so steep I have to get way out over the bars to keep from flipping over which is why I don't stop until the top. Generally it is less than 500 meters of this grade and it isn't constant so I can get a break on it if I have to.

Batteries seem to be the most variable component out there and there are a lot of ideas on what to do with them. I rebalanced, rebuilt my Honda Hybrid battery system so I am somewhat familiar with the concepts. I am not eager to mess around building packs so IMHO buy one off the shelf the first time. As mentioned earlier Ping batteries seem to be ideal or go with one of these off the shelf batteries like I bought. There are a lot of them out there and many are LiFePO4 cell based. I do plan to build an off road bike with high voltage and high wattage but it will have to wait as this project cost me roughly $750 total. She who must be obeyed, wasn't all that happy with it, however, I am hearing she might like it for her bike as well. That would be great as she won't ride with me at all even down to the lake so maybe this will get her out on her bike again. Motivating a 65 year old woman to go cycling is difficult so perhaps this might do the trick. I have her sister's 12 year old grandson coming again the Summer and he is going to be insanely jealous so I am pretty certain I will be building at least one more ebike if not 4 more (the grandson, the mother of the grandson, my sister-in-law, and my wife). They all have bikes hanging in the garage and typically when they visit we all ride down to the lake together. But the 2 older ladies are pooping out these days and not riding any more. Age takes its toll so I think an ebike conversion for them might be well appreciated. My grandson-in-law has a good mountain bike but is basically lazy and definitely doesn't like riding uphill on hard trails so for him it would be beneficial as well. The ladies are all on beach cruisers.

I am watching the battery technologies changing though so am taking a wait and see attitude. Likely, I'll end up making the mid mount entirely myself as the GnG kit seems to have a lot of problems. Anyway, it is a somewhat complex subject which can get expensive. Really, it all depends on usage and expectations.

I forgot to mention one big consideration is that batteries are more or less a consumable and likely won't last more than 2 years so you have to figure that into the equation. I am loathe to shell out big money for a battery pack that I'll have to replace in 2 to 3 years. I have a lot of experience on this as I am running a small solar system to run the pumps for my 20,000 gallon fish pond. I am using a 120 Watt panel with a smart charge control system into a 45 Ah deep discharge gel battery. If I am extremely lucky I get 2 years out of a battery. It is for that reason I am not going to go off grid with a photovoltaic system using a battery system. It is a conscious choice based on the battery costs and problems associated with them. I will instead do the Feed In Tarrif (FIT) calculations and tie into the grid. She Who Must Be Obeyed likes this idea and I will likely also install 2 smallish wind generators as well. As we live in a thermal hot spring area I am also looking hard at drilling a deep (500M) well to tap into the hot water to heat the house and possibly drive a 1,000 Watt Stirling generator. The real question is how deep and what is the temp of the water but I have some neighbors who did this (although I can't seem to be able to connect with them) so I can get some idea of the realities of doing this. Living in Hungary has some language and conceptual issues so it isn't always easy to do these kinds of things. Japan is likely similar.

 

[dogman dan]

What you want is a bit optomisitc, but you will find that if you can charge reasonably fast, you may not need to carry enough battery for 100km of continuous riding.

What I mean is, if you will ride someplace and then be there awhile, you can just recharge.

Range will depend on the speed you ride. Assuming you get a 9c motor or similar direct drive hubmotor, you will want a 48v 20amps controller to achieve top speeds of 45kph-50kph.

48v 20 ah is a bit on the cumbersome side to carry on bikes, but 48v 15 ah is not so bad. For this reason I tend to recomend a 48v 15 ah lifepo4 from pingbattery.

48v 15 ah takes me the following distances. Range depends on the speed, distances assume either flat ground, or at least not 100% uphill.
40 kph= 30-35 k
35kph=35-40k
30kph=50-60k

So 100k is entirely possible with only 48v 15 ah by charging while you work, visit a freind, eat, etc.

Your budget should easily pay for a hubmotor kit, 48v 15 ah pingbattery, and a cycleanalyst or other wattmeter. Get it going, ride some, and then decide if you want to buy a second battery to further extend range.

DO NOT MAKE THE MISTAKE OF BUYING TOO BIG A BATTERY TO BEGIN WITH, such as 48v 30 ah. 48v 20 ah max. If you get that, make sure it comes in two peices so you can carry half in each pannier. You really won't want to carry 30-40 pounds of battery on every trip. 48v 15 ah should be close to 15 pounds, and much nicer to ride with on 90% of your trips.

 

[borschelrh]

Dogman, Your advice is sound but please correct me if I am wrong, but your setup is if you don't pedal at all (or not very much). Pedaling can increase this range a lot, especially if there is some regen. I do agree 48V will give a lot more power and I am a bit underpowered which I am okay with as I am a strong rider and I like to ride hard. The extra weight is a big factor as well so it is a big tradeoff with regards to power to weight, especially if for some reason the system craps out and all you have left is pedaling. I can still pedal my rig although without the assist it is roughly 30% more effort. I turned off the system to check it and I can still ride it without power but typically in lower gears and slower speeds. That is another consideration, what to do on a 100km ride if it fails. Murphy's Law says that will happen at the worst possible time (furthest away from home) and under the worst possible conditions (pouring sleet, hail, or rain), and your cell phone will be dead. Forty years in the Army taught me to not only plan for this but to expect it and I am never disappointed. We would call it good training. My name back when I was still a Sergeant in the Army (I was commissioned after 10 years) was Mr. Destructo as everything I ever used failed so I am a good worst case systems test. That was not particularly good when I was a helicopter pilot (I had 2 birds with major systems failures and dead stick landings) or in SF when parachuting. I have had 2 different C-141 aircraft catch fire (and crash after my stick got out which is fun to watch from the air) when I was on night jumps and on one of those jumps my main parachute also failed. None of this was ever bad enough to kill me though but I do seem to live under a dark, however quite interesting, cloud.

 

[agniusm]

If speed and power is not primary requirement you could look into nmc or lg cells. they are good to about 2c max but you win win on weight. I have seen somewhere lg cells for 3usd each at 3000mah.
14s10p would work out 420usd plus shipping and weigh 6kg and that equals 20ah a123 cell pack at 8kg. U get less cycles but the price is half A123. For low power I would not consider any other option and with 30ah pack thats 30a constant with 60a burst which is plenty.

 

[johnjapan]

What you want is a bit optomisitc, but you will find that if you can charge reasonably fast, you may not need to carry enough battery for 100km of continuous riding.

What I mean is, if you will ride someplace and then be there awhile, you can just recharge.

Range will depend on the speed you ride. Assuming you get a 9c motor or similar direct drive hubmotor, you will want a 48v 20amps controller to achieve top speeds of 45kph-50kph.

48v 20 ah is a bit on the cumbersome side to carry on bikes, but 48v 15 ah is not so bad. For this reason I tend to recomend a 48v 15 ah lifepo4 from pingbattery.

48v 15 ah takes me the following distances. Range depends on the speed, distances assume either flat ground, or at least not 100% uphill.
40 kph= 30-35 k
35kph=35-40k
30kph=50-60k

So 100k is entirely possible with only 48v 15 ah by charging while you work, visit a freind, eat, etc.

Your budget should easily pay for a hubmotor kit, 48v 15 ah pingbattery, and a cycleanalyst or other wattmeter. Get it going, ride some, and then decide if you want to buy a second battery to further extend range.

DO NOT MAKE THE MISTAKE OF BUYING TOO BIG A BATTERY TO BEGIN WITH, such as 48v 30 ah. 48v 20 ah max. If you get that, make sure it comes in two peices so you can carry half in each pannier. You really won't want to carry 30-40 pounds of battery on every trip. 48v 15 ah should be close to 15 pounds, and much nicer to ride with on 90% of your trips.

you bring up an excellent point about not getting a big battery.
I'll mostly be using my bike for commuting between work so the idea of charging it at work is a great idea! that would give me the range for going back home.


ill go with the 48v15ah

Im still unsure about which motor kit to get with this id like the most compatible and energy efficient one.
I would also like my gears to be functional with this motor if I choose to switch to full leg power