Electric bike options? make my bike electric or buy one?

Hello, I need all the bike and electrical geniuses help please. Electrical is one thing I'm not very good at, mainly because I have zero experience with it other than installing a car stereo.

I need a replacement to my Currietech Ezip Trailz ebike. I have a disability that does not allow me to walk very far distances or hills, etc. For long distances, I use an electric bike. I guess you can say in lieu of a wheelchair. I dont need an actual wheelchair esp since I can walk and maneuver in buildings but it's the long distance stuff that really wears me out and is difficult for me. I have been chucking my Ezip into the back of my truck and taking it with me whenever I felt like I would need it. For example, going to the beach or the park, going to a football game and tail gating, etc. It gives me mobility that I otherwise would have difficulty having. Unfortunately, I do not have a truck anymore, but a very small car. The SLA battery is too heavy, the bike itself is too heavy, the charging maintenance on SLA is very cumbersome. For someone who requires this bike for assistance physically, it's not the best bike because it lacks the most important thing: Portability.

It doesn't fit in my car and I've looked into racks but it doesn't solve the problem that the bike + battery is just too heavy and outdated for me. I want to upgrade.

I am looking for a very portable YET capable e-bike. The ideal bike would be an electric mountain bike that weighs less than 50 lbs or so. My Ezip Trailz comes in at a whopping 68 lbs with the SLA battery. I can't even pedal that sucker for more than a mile on a flat road without getting tired. I'd be stranded if the battery gave out, which would leave me in a worse situation than if I did not have the bike. I went to 4 different bike shops, 2 of them selling only electric. I've done my research on the electric bikes that are sold as E-bikes. They are very pricey. So my question is, are there any cheaper DIY alternatives???

What I found was that there are:
1) folding e-bikes such as the e-joe, e.g., emotion, brompton, Dahon, etc. but they are SO expensive/ $1200-1500. It is very portable and would fit in my small car's trunk, I can take it pretty much anywhere I go. But it's not very capable. The tires on these type of bikes are very small, they are very comfort style bikes and my feeling is they would not last riding on grass or dirt if the need arose. It doesn't happen often but it does happen sometime and I would like the capability to ride a trail every now and then or go on the grass.

2) Non-folding ebikes such as other versions of the currietech ezip and izip line, prodeco, etc. These are good because their prices can be found arond $550-1000, AND they would have lithium ion and be lighter compared to my Ezip trailz. I would love for it to fold but I do not know of a single brand that folds AND is a mountain bike design with wider tires and at least a 500w motor to handle off road every now and then. If these exist, please fill me in! I've been to 4 bike stores, no one has these.

3) Folding regular mountain bike such as the Montague lines + electric bike conversion kit. Montague bike such as this one: http://www.montaguebikes.com/paratrooper-folding-military-bike.html
This is THE perfect bike because it folds, it's rugged, it's light at about 25 lbs. It's portable and capable. It has gearing in case I want to pedal, it looks great. Price is okay.
The problem is it is NOT electric. Therefore, if there is some cheap way to DIY electric conversion this bike such as a front wheel hub motor, this bike would be the perfect solution.
Does anyone have any input on this??

I have looked into trying to tear off all the motor and electrical components off my currietech and installing it onto a Montague but it looks like it will not work. The motor is a rear wheel motor it requires drilling, special fabrication and bracket to hold the motor in place, not to mention the width of the rear wheel might be different, ugh.. too incompatible.
The only option it looks like to me, is a front wheel hub motor. A simple motor that provides power with a thumb throttle. I looked online and some are going for only $150 or so for the conversion kit. I have found this one on Craigslist: http://orangecounty.craigslist.org/bid/4143970476.html
http://orangecounty.craigslist.org/bid/4143968735.html

What do you guys think? The biggest cost is the lithium battery. Is there a way to install the hub motor and cut down on the battery cost? I've seen 6s LIPOS wired but I do not really understand it very well and I read that the range isnt as good? Or it is flame prone?

Sorry for the long post but I'm hoping someone can help me out here with some advice. Thanks.

Building your own bike from a kit isn't really difficult, but you do need to be able to do your own maintenance on your bike. A mountain bike conversion will probably weight about 80 pounds using Lipo batteries. Mine is a full suspension bike 1000watt 48v conversion with cargo racks, lights, and weighs almost 95 pounds with 4 bricks (8 5000 mah lipos). I also carry an extra tire tube and foot pump. I fly large RC model planes using 2 5000 MAH 6S batteries at one time so I have no problems using lipos. I also have the powerful chargers necessary to charge 8 packs in about 2 hours. Fire has never been a problem on my E-bike and as far as I am concerned is not a problem. Lipo fires (problems) occur when the batteries are over charged, over discharged, or in a very serious crash as in high speed RC plane crashes. The kit you listed seems OK, but I would recommend you add head and tail lights, horn, and maybe a bike center stand. If peddling a bike is a problem, them I would really look at getting a simple reliable E-bike of the 500 watt size as batteries are smaller, stay away from the high power bikes as they can have more of a maintenance issue.

ridiqls said:

What do you guys think? The biggest cost is the lithium battery. Is there a way to install the hub motor and cut down on the battery cost? I've seen 6s LIPOS wired but I do not really understand it very well and I read that the range isnt as good? Or it is flame prone? .

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You may want to read through my now infamous Cautionary tales of fires before deciding on LiPoo.

if you can hump a ezip with SLA into the bed of a pickup you can hang an ebike built using a regular bike and hubmotor on a bike rack.

it is best to have the battery in the middle of the bike but you may need to remove the battery to hump it onto the bike rack if i understand the limits of your ability.

you can buy rear hubmotor in LA too from the yescomusa guys too.

read up on how people mount their lifepo4 packs. there is not the risk or the short lifespan of lipo if that is a concern. they last longer, safer than lipo, but about 30% heavier. or less if you end up with the laptop lipo cells.

dnmun said:

if you can hump a ezip with SLA into the bed of a pickup you can hang an ebike built using a regular bike and hubmotor on a bike rack.

it is best to have the battery in the middle of the bike but you may need to remove the battery to hump it onto the bike rack if i understand the limits of your ability.

you can buy rear hubmotor in LA too from the yescomusa guys too.

read up on how people mount their lifepo4 packs. there is not the risk or the short lifespan of lipo if that is a concern. they last longer, safer than lipo, but about 30% heavier. or less if you end up with the laptop lipo cells.

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Thanks. I no longer have the truck though which is the problem. I do not have a bike rack either and while it is certainly an option to get one, if I find one that folds (preferably) that does what I need then it would make my life that much easier. No need to haul it up stairs and into my house or apartments, no need to worry about it getting stolen off my car, no need to install a hitch rack (the best and most expensive solution for my 350z) and alter the look of my car and spend money where it can go to the cost of the bike. Well, that's what im hoping for anyway. I'm not opposed to getting one but a folding bike would make everything so much easier.

I found a bike rack called the seasucker which are vacuum cups that hold your bike on your window and roof, etc. They are marvelous but at a price of almost $300 with no protection against theft, it's something that I would rather see as an alternative to a bike that will fit in the trunk.

heavymetalthunder said:

Building your own bike from a kit isn't really difficult, but you do need to be able to do your own maintenance on your bike. A mountain bike conversion will probably weight about 80 pounds using Lipo batteries. Mine is a full suspension bike 1000watt 48v conversion with cargo racks, lights, and weighs almost 95 pounds with 4 bricks (8 5000 mah lipos). I also carry an extra tire tube and foot pump. I fly large RC model planes using 2 5000 MAH 6S batteries at one time so I have no problems using lipos. I also have the powerful chargers necessary to charge 8 packs in about 2 hours. Fire has never been a problem on my E-bike and as far as I am concerned is not a problem. Lipo fires (problems) occur when the batteries are over charged, over discharged, or in a very serious crash as in high speed RC plane crashes. The kit you listed seems OK, but I would recommend you add head and tail lights, horn, and maybe a bike center stand. If peddling a bike is a problem, them I would really look at getting a simple reliable E-bike of the 500 watt size as batteries are smaller, stay away from the high power bikes as they can have more of a maintenance issue.

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Thank you. I'm going through and watching a million videos of all the different folding and non folding bikes out there as well as ebikes. Wow 80 lbs.. yikes. Maybe a DIY conversion kit for me a bit too ambitious then, esp adding in the cost of the batteries AND the headache that will ensue for a newbie like myself.

Question: Is wattage everything when it comes to the bike's ability to handle uphill and various terrains? For example, I will use my Currietech Ezip TrailZ as the benchmark. I have some hills in my neighborhood and like riding uphill on them with my dog next to me on the bike because it tires her out faster. I do not pedal on the ezip and only use full throttle mode usually (the pedal assist on it is real weak anyway). I have no problem going uphill on an used SLA battery with the bike weighing 70+ lbs. It burns the battery faster but due to the motor being 500w, it has even power to handle it going uphill all the way for a good 20-30 min bike ride. Best of all, it does NOT slow down. It can maintain the 15mph speed.
Will a 250w or 350w small wheel folding e-bike be able to do the same thing? I dont know how the smaller wheel diamter will come into play here for going uphill. Apparently being that it's a Lithium ion battery, they can even go up to 20 mph despite the 250w motor, which is HALF that of my ezip. Here is an example: http://orangecounty.craigslist.org/bid/4109678457.html
I test rode that one and it was noticeably faster than my ezip but it could've been due to being lithium and a brand new battery. How will that 250w fair going uphill for a good 30mins-1hour, maybe about 5 miles?

I initially ruled those out cause the small wheels reminded of like a circus bike or something. but they are starting to grow on me. They have portability, just do not know if they have the capability.

Question 2: How will those small wheels and 250w motor fair if I take this on dirt trails and grass fields? Benchmark against my ezip trailz... my ezip I can ride full throttle on the school grass field without a hitch. Again it will burn up the battery really fast if I do that but at least I know the bike itself is capable of doing that due to the bigger tires. I also took the bike on a dirt trail that also went uphill and downhill and it had no problem.

How would a small wheeled folding e bike fair in offroad terrain? Nothing insane, no rocks or jumping. Just dirt or grass type situations.

Thank you for the help everyone.

Hmm, lots of needs and not much money makes me want to take my advice in about 2 or 3 different directions.

1 first thing, I'd say if you build your own bike, you need to start with a good lithium battery. Lifepo4 such as a pingbattery for your existing bike might be all you really need to keep using it. Not changing bikes could save you money.

2 it might be possible to strip your current motor off the bike you have, and install it on a folder.

3 But a good bike rack would mean you don't need the folder. But that doesn't make it as secure as the trunk. Obviously if you left the bike on the rack at all times, it would disappear.

Conclusion, try a lithium battery on your existing bike, while hunting for an affordable folder you can move the motor to.

If you had money, then it would be possible to point you to folding ebikes that are ready to ride. But without money, I think adapting what you have might be best. If you find an affordable 250w folder, it will do the majority of what you need, such as mobility on a large flat event or beach area. It will fail on steep trails for sure. Your existing bike does climb a hill very nice, so for that you should stick to it. Just dump that heavy lead.

If it's in your budget, maybe get that folder, but then plan on some kind of battery improvements to your Currie for trails. Carry to the trails on a rack of course.

dogman said:

Hmm, lots of needs and not much money makes me want to take my advice in about 2 or 3 different directions.

1 first thing, I'd say if you build your own bike, you need to start with a good lithium battery. Lifepo4 such as a pingbattery for your existing bike might be all you really need to keep using it. Not changing bikes could save you money.

2 it might be possible to strip your current motor off the bike you have, and install it on a folder.

3 But a good bike rack would mean you don't need the folder. But that doesn't make it as secure as the trunk. Obviously if you left the bike on the rack at all times, it would disappear.

Conclusion, try a lithium battery on your existing bike, while hunting for an affordable folder you can move the motor to.

If you had money, then it would be possible to point you to folding ebikes that are ready to ride. But without money, I think adapting what you have might be best. If you find an affordable 250w folder, it will do the majority of what you need, such as mobility on a large flat event or beach area. It will fail on steep trails for sure. Your existing bike does climb a hill very nice, so for that you should stick to it. Just dump that heavy lead.

If it's in your budget, maybe get that folder, but then plan on some kind of battery improvements to your Currie for trails. Carry to the trails on a rack of course.

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Thanks, great advice. I'm considering it all. I'm also considering regular bikes without electric because they are much easier to ride than I last remember. The last time I rode a bike was in college and being a newbie to the bike world, I never knew you could get 17lbs carbon fiber bikes used off craigslist for under a grand. I could also try to rig my current trailz with the lifepo4 as you suggested but while that would give me everything including range and capability, doesn't give me much portability.
I guess you are right, Money, Capability, Portability. Choose 2 out of 3.
I could buy a folding road bike that is very easy to ride, something like a Montague weighing in at about 25 lbs for most things and then work on upgrading the trailz for the latter I guess.

Last option would be to get a Prodeco as those are built like mountain bikes but are electric and have 500w. Basically a better version of my trailz with the portability. http://orangecounty.craigslist.org/bid/4084055712.html
Pricey and heavy.. if the battery dies, I'm pretty much stranded with a 60 lbs bike haha
but will look into this. I spoke with a local bike shop and the guy was very cool. Super nice, explains in details and he gave me about 5 reasons why Prodeco as a company is garbage. Much research to be done..


Thanks for the help!

Unless its concerning the ability to pick up and carry your bike, weight isn't a big deal. If you weigh 150 Lbs. and your bike is 50 lbs. adding 40 lbs. is only 20% heavier.

ridiqls said:

The last time I rode a bike was in college and being a newbie to the bike world, I never knew you could get 17lbs carbon fiber bikes used off craigslist for under a grand.

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Again, as a percentage of total weight, its not the miracle that some would have you believe.

Your eZip has a 35A controller. If you get a lithium battery for your 35A eZip, make sure it can handle a 35A draw. I'd think a battery made with A123 26650 cells would be a good match for the eZip 35A controller.

If you want to make the eZip easier to pedal, get some low rolling resistance street tires or tires that have smooth centers and knobbies on the sides for your off-road action. The stock eZip Trailz knobbies have great traction, but consume lots of power in rolling resistance.

I have a Currie 2008 EzGo folding bike with 16" wheels and although I like it fine for speeds under 15 MPH, it did take some practice to get comfortable with the handling. The ability to easily put it in the trunk is fantastic. I'd look for a folder with 20" wheels if I ever replace it, however.

i found a thule bike rack in the recycling once and took it apart and swapped the arms in a different orientation so i could hang it over the back door of my honda wagon. it was hooked over the door and the support bar pushed against the bottom half. i had to make hooks outa chain and opened a link to make a hook. trying to convert it to my new wagon now. i like having the metal hook to the solid part of the frame on the rack that the thule design has. i can't use a big hitch rack on the honda wagon either.

dnmun said:

i found a thule bike rack in the recycling once and took it apart and swapped the arms in a different orientation so i could hang it over the back door of my honda wagon. it was hooked over the door and the support bar pushed against the bottom half. i had to make hooks outa chain and opened a link to make a hook. trying to convert it to my new wagon now. i like having the metal hook to the solid part of the frame on the rack that the thule design has. i can't use a big hitch rack on the honda wagon either.

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I am looking at an option of buying a Montague bike, such as the swiss x50 or the paratrooper. Preferably used. And then adding a front driven hub motor wheel. The bike is rougly 29 lbs so this would make the weight about 45 lbs, 50 lbs at most including the battery (if lithium).

The new x50 and paratroopers come with disc brakes. So if I buy an ebay or craigslist kit that comes with a controller, throttle system, front 26" wheel hub motor, how will this be installed? Will the disc brake get in the way?

ASSUMING the bike is already purchased, how much $ would be a good budget estimate for a front wheel hub motor system. Nothing fancy. in fact, i can pedal if it's flat roads, i just need it to go up hills and use when necessary (i.e. im tired, hills) if I manage to get a kit and DIY. What is the cheapest yet easy and durable way to cut costs on a front wheel conversion?
For convenience, I can always buy a hill topper motor conversion kit for about $499 but it comes with a dinky light lithium battery called a sprinter. 4.4AH rated at 10 miles! That's pretty weak. Their 10ah rated is 20 miles and costs a whopping $800. If I can somehow achieve the same or similar results but for way less than $800 for a 10ah equivalent, anything that will help last me up the hills, that would be perfect.

A montague x50 is $650 + tax, about $700. If I can wait and be patient, I can maybe find one used on Craigslist. There are a few already like a paratrooper for $570 and a MT for $320 but the paratrooper is a single gear conversion (I would have to change it back. It's an older model so doesn't have disc brakes but he did upgrade to nice v-brakes and put in a lot of money upgrading everything else). The MT is too big of a size. I'd like to hope for an used montague to come up soon for about $400-450. And if I can manage to cut the price down on a front wheel conversion kit to about $400-500, that would be perfect for me. That way I have a bike that's completely capable, foldable, light (for electric standards at about 50lbs), with good range.

A few pitfalls to watch out for. Many folding bikes have an 80 mm front fork. Hubmotors are usually made for a normal 100mm front fork.

So you would have much trouble finding a motor that fit an 80mm fork at all, let alone be able to cram a brake disk in there too.

I would not recommend the prodeco very highly. But if you need a folding ebike, that is one.

4-500 bucks buys a decent battery. Not a whole kit.

dogman said:

A few pitfalls to watch out for. Many folding bikes have an 80 mm front fork. Hubmotors are usually made for a normal 100mm front fork.

So you would have much trouble finding a motor that fit an 80mm fork at all, let alone be able to cram a brake disk in there too.

I would not recommend the prodeco very highly. But if you need a folding ebike, that is one.

4-500 bucks buys a decent battery. Not a whole kit.

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"Fork SR Suntour. Suspension XCT V4. 80mm travel. Alloy one piece lower. Disc Compatible."
That is what it says on Montague's website under the paratrooper's technical specs. 80mm travel you are talking about? Or are you talking about the width?
Is it possible to change out this fork and upgrade it to a standard 100mm or will it cause some other component incompatibility?

EDIT: I actually called the company of the electric bike distributor, and Montague. Both hub widths are 100mm in front and 135mm in rear. I'm going to go with rear if I do this so I dont have to worry about the fork bending or what have you.

A 36v Lithium Ion battery with a 700w or 1000w motor is $689 and I can local pickup. Does this sound about right for pricing?

Yes that is a fair price for a good quality 36 volt battery pack.

ridigls;

I may have a suggestion for you. First, do you know how far you need to travel?

I bought as my 1st ebike conversion, a Clean republic ebike. It uses a bafung front wheel 26" wheel, that you can convert any bike over to ebike in 15 minutes, they claim 5 minutes. It is simple,it doesn't use a throttle, just a sort of an on/off switch, which really work well. I have been using it for the past 3 years, only major change was batteries, sla to Life to Lipo, voltage from 24v to 36v to 48v. it run great, no problems. My kit purchase 3 years ago was $400 sla batteries included. If you are interested in this route, don't get the sla batteries, go with a Ping( Life) or build your own Lipo setup.I currently have on the bike eight 6s 5a Turniqy LIPO batteries at about $48 per battery, which gives me about a 32 mile range. If you are going under 20 miles you can use just 4 of the batteries, which would be 2s2p. Catch is you will need a good charger and power supply about $150. Bike weighs about 30 to 40 pounds.
I wouldn't consider the yescomusa kit, beause it is heavy, I have one, the bike loaded weight around 100 pounds, really hard to get out of the house, especially if you have to go down some stairs. It's a great kit, really fast in stock form, I use it on our Bike the drive ride, where you could really get some speed and in a safe environment. So, my next suggestion is small wheels. Five of my 7 ebikes are small wheels, 20 inchers and one ebike is 16 inch wheels. Advantage....lighter, easy to transport, maybe around 20 pounds, fast acceleration from stop, weird looking, gets attentions easily. Disadvantage...20 to 25 mph max. Just get a BMX bike and convert over. I use either bare bafung or cutie 80 motor and spoke the wheels myself.
Sorry about talking so much, it is just there so much info to reveal. Here's the link to the 5 minute convern by clean Republic.

http://www.electric-bike-kit.com/hill-topper.aspx

by the way....where are you located, may be able to help you even more.

thanks

Jerry

chisixer6 said:

ridigls;

I may have a suggestion for you. First, do you know how far you need to travel?

I bought as my 1st ebike conversion, a Clean republic ebike. It uses a bafung front wheel 26" wheel, that you can convert any bike over to ebike in 15 minutes, they claim 5 minutes. It is simple,it doesn't use a throttle, just a sort of an on/off switch, which really work well. I have been using it for the past 3 years, only major change was batteries, sla to Life to Lipo, voltage from 24v to 36v to 48v. it run great, no problems. My kit purchase 3 years ago was $400 sla batteries included. If you are interested in this route, don't get the sla batteries, go with a Ping( Life) or build your own Lipo setup.I currently have on the bike eight 6s 5a Turniqy LIPO batteries at about $48 per battery, which gives me about a 32 mile range. If you are going under 20 miles you can use just 4 of the batteries, which would be 2s2p. Catch is you will need a good charger and power supply about $150. Bike weighs about 30 to 40 pounds.
I wouldn't consider the yescomusa kit, beause it is heavy, I have one, the bike loaded weight around 100 pounds, really hard to get out of the house, especially if you have to go down some stairs. It's a great kit, really fast in stock form, I use it on our Bike the drive ride, where you could really get some speed and in a safe environment. So, my next suggestion is small wheels. Five of my 7 ebikes are small wheels, 20 inchers and one ebike is 16 inch wheels. Advantage....lighter, easy to transport, maybe around 20 pounds, fast acceleration from stop, weird looking, gets attentions easily. Disadvantage...20 to 25 mph max. Just get a BMX bike and convert over. I use either bare bafung or cutie 80 motor and spoke the wheels myself.
Sorry about talking so much, it is just there so much info to reveal. Here's the link to the 5 minute convern by clean Republic.

http://www.electric-bike-kit.com/hill-topper.aspx

by the way....where are you located, may be able to help you even more.

thanks

Jerry

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Jerry, I am in southern california.
I am still deciding on the distance and range I need. The bike isn't used for commuting but due to my situation, it is an extension of my car. I will use it to take me around places where the car isn't allowed and long distance walking is required. One real life example that recently came up about 2 weeks ago, there was a football tail gate for the UCLA game. I wanted to go but I couldn't because the walking distance was too much. The tail gate occurs on a very large GOLF course. Miles of cars parked all over the course. Cars that get there late park down hill near the residences and street park. You could imagine for someone like me, I couldn't even make it to the stadium entrance having to walk up 2 miles uphill, then down a mile, then walk a mile over a golf course, then traverse a big stadium parking lot to get to the entrance of the stadium. I have to use the restroom? Crap, guess I gotta walk back another mile. Not happening for me.
But if I had an ebike, I can park wherever the hell I want. I can park downhill where all my friends are parked, take out my folding bike or whatever I choose as my ebike, then pedal and throttle around no problem. Then I lock the bike up near the entrance in a very public place, walk around in the stadium and enjoy the game. I can walk around inside places, buildings but like I said, it's the large venues and buildings that give me trouble.
So I would say that even a 10 mile range could be enough but I don't want to find out that it's not. Cause then I'm stranded with a 50lbs+ bike that I can't pedal back. If that was the case, I'd rather have a 16lb road bike, which I COULD probably pedal back? It's just not foldable and it's not EASY to do uphill.
Realistically, I would say a 20-30 miles rating would be sufficient. I dont need high pedal assist on flat roads, maybe medium or low setting. I will need high or full throttle when going up hills. And when going uphill or on rugged dirt or grass, the battery wears out much quicker so a 20-25 mile rating could drop down to 10 miles or less which is fine.


I need to know/research more about Life/LIPO/LithiumIon differences. The kit that a distributor on CL sells is $680 for the entire kit including a 36v lithium ion battery. I want to reduce this price somehow if it is possible. The best way for me to know is to find the right battery for my need.
Here is the kit: http://losangeles.craigslist.org/lgb/bid/4143005324.html

As you can see, if i buy it without the battery as seen here: http://losangeles.craigslist.org/lgb/bid/4143085978.html, I can possibly cut costs if I get the battery for less than $400.
The guy said the entire kit will add about 25lbs including the battery weight.

UPDATE: Today I went to a bike shop and checked out a few dahon folding bikes. I narrowed the choices down to a Dahon or a Montague. Going to the store made it real easy for me cause, the dahon barely fit in my car's trunk hah! so montague was out. The shop didn't have the one I was looking for. I ended up picking up a brand new red Dahon on craigslist for $400. Although, I wonder if I should have gone single gear cause they had single gears for $200. But I figured $200 vs $400, throw in some consumables like tire, brake, chain, etc. and it's the same price. So went with the brand new one with 8 speeds.

Question:
Would you guys personally remove the gears and go single speed to reduce some weight? Because although gears are great, if I'm going electric I won't need the ones to go uphill. I'll use the throttle instead. And I wont need gears on flat roads that much. Reducing weight will increase the range on the bike. The bike comes in at 26.2 lbs. Not a big but if I add 25 lbs of electric, it will be around 46 total.



I'll do some research on the different lithiums and then come back with which voltage and AH to look for.

Regarding the forks, I was talking about the width of the dropouts. They are often narrower on the folders, particularly the 20" wheel ones.

So if you have a 135 mm wide rear motor, and your dropouts in the back are only 120mm it's a dilemma. Not a complete stop, but you would have to do some modifying. A steel frame can be bent wider, an alloy frame cannot.

We have a resident folding bike expert here that can help you more than I can. Maybe make a folder thread later when you are down to picking one out.

If you buy a motor first, you might be stuck with what that motor will fit.

Pick a bike,
Pick a motor
Pick the battery, in that order.

Lastly just to make picking a bike even harder, have you looked at small non folding bikes? Like a bmx?

ridiqls said:

I am still deciding on the distance and range I need. The bike isn't used for commuting but due to my situation, it is an extension of my car. I will use it to take me around places where the car isn't allowed and long distance walking is required...

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Right on! Wish more newbies entering the ebike fray would start like that - really considering the use BEFORE embarking on a build. What you build needs to match use, because there are lots of different component choices, depending on that.

I need to know/research more about Life/LIPO/LithiumIon differences. The kit that a distributor on CL sells is $680 for the entire kit including a 36v lithium ion battery. I want to reduce this price somehow if it is possible. The best way for me to know is to find the right battery for my need.

Click to expand...

You'll get a lot of different opinions and this here at ES. My recommendation is stick with LiFePO4. See this great article on the subject. A bit technical but there's a lot of good information in it.

I'll do some research on the different lithiums and then come back with which voltage and AH to look for.

Click to expand...

Voltage match to your motor and get 100% more AH than your average distance. That will cover a> longer rides than average, b> keeping in the safe discharge range, leaving 30-40% of capacity minimum, and c> accounting for capacity loss over time, as the battery ages.

ridiqls;
Okay, you got a Dahon folder, not sure what size wheels are on it, and you got an 8 speed. I think you will need a front driver, otherwise your 8 speed is wasted.Since you got a folder, looks like the triangle section of the bike won't be able to mount your battery unless you do an elaborate mount(this is the ideal place to mount a battery, because of center of gravity and handling.). You will probably mount on a rear rack(get a strong one, batteries have some weight, especially if you bounce around on off road.Choice of battery is now Lifepo4 or Lipo. Notice there is a good recommendation for the Ping battery(Lifepo4), and it is safer, plug and play.
That epower kit is very similar to the yescomusa kit, motor is direct drive, advantage....fast, no internal gears, disadvantage....heavy, and a little more difficult to pedal with no power, as it doesn't freewheel like a geared hub. the battery that it shows is only 11a, maybe good for 15 to 20 miles. Try to get at least 15a, if you use it for about 20 miles, you don't want to run out of juice miles from home.
The motor then for you would be geared hub, it's lighter and it freewheels, so you can pedal easier without power. when you go up a hill, tried to pedal too, so that you won't use up your battery.a small geared hub is maybe 10 pounds or under, where as a direct drive is about 20 pounds or more. fiqure your 20a battery to weigh about 15 pounds depending on size.
You can probably get away with a 24v motor, 250watts, give top speed around 18mph, cruise in the low teens.On a 10a battery you can probably get at least 15 miles. Want to go faster you can overvolt by going to 36v or even 48v, where you can cruise in low 20's and max speed uper 20's.
example my clean republic kit comes with 24v and 250 watts motor and a 15a controller, at 1st 24v sla(top speed 18mph) . just changing the batteries to its current state of 48v( top speed in upper 20's) , with everything stock(controller capacitors can go to 50v). I use this bike to commute on flat roads 18 miles to work and 18 miles home with 20a Lipo batteries.

Jerry

chisixer6 said:

ridiqls;
Okay, you got a Dahon folder, not sure what size wheels are on it, and you got an 8 speed. I think you will need a front driver, otherwise your 8 speed is wasted.Since you got a folder, looks like the triangle section of the bike won't be able to mount your battery unless you do an elaborate mount(this is the ideal place to mount a battery, because of center of gravity and handling.). You will probably mount on a rear rack(get a strong one, batteries have some weight, especially if you bounce around on off road.Choice of battery is now Lifepo4 or Lipo. Notice there is a good recommendation for the Ping battery(Lifepo4), and it is safer, plug and play.
That epower kit is very similar to the yescomusa kit, motor is direct drive, advantage....fast, no internal gears, disadvantage....heavy, and a little more difficult to pedal with no power, as it doesn't freewheel like a geared hub. the battery that it shows is only 11a, maybe good for 15 to 20 miles. Try to get at least 15a, if you use it for about 20 miles, you don't want to run out of juice miles from home.
The motor then for you would be geared hub, it's lighter and it freewheels, so you can pedal easier without power. when you go up a hill, tried to pedal too, so that you won't use up your battery.a small geared hub is maybe 10 pounds or under, where as a direct drive is about 20 pounds or more. fiqure your 20a battery to weigh about 15 pounds depending on size.
You can probably get away with a 24v motor, 250watts, give top speed around 18mph, cruise in the low teens.On a 10a battery you can probably get at least 15 miles. Want to go faster you can overvolt by going to 36v or even 48v, where you can cruise in low 20's and max speed uper 20's.
example my clean republic kit comes with 24v and 250 watts motor and a 15a controller, at 1st 24v sla(top speed 18mph) . just changing the batteries to its current state of 48v( top speed in upper 20's) , with everything stock(controller capacitors can go to 50v). I use this bike to commute on flat roads 18 miles to work and 18 miles home with 20a Lipo batteries.

Jerry

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Thank you for the help, I haven't considered some of those!

My Dahon is a Speed P8, it has 20" wheels. I was told by the guy selling the ePower kit that the rear gears will not be affected even if you put the motor in the rear. Isn't the cassette on the outside of the hub? I dont really know the mechanics of that.
Wheel placement: Actually I was going to do a front motor because the Dahon doesn't require me to remove the front wheel such as the Montague. But the fork is aluminum! "DAHON SLIPSTREAM, DALLOY ALUMINUM, PATENTED FUSION TECHNOLOGY, DOUBLE-BUTTED TUBING" I was told the torque would break or bend the fork so I either have to change the fork to steel or go with a rear motor. If that is the case, I need to figure out whether it is not possible for sure to keep the gears useful AND have a rear hub motor. My ezip Trailz has gears and it is useable but it's run by an external motor with a chain. Also the E.G. ebikes and Ejoes have 7 speeds without a problem. I'm uncertain about this.


Battery Placement: I can either go with a rear rack and battery or I was also considering a water bottle type to put on top of the frame where there are already holes for placement. But I need to consider how it will affect the folding of the ebike.

Battery power: I need help with deciding how much power I need. I did some reading and I have decided against Lipos. I have had some experience (very little) with Lipos with my rc car and the way they are high maintenance, have higher risk and require expensive chargers, etc. is not something that I prefer. My only choice is LifePo4 i guess. But I'm confused how lifepo4 is also referred to as lithium polymer. Isn't that the same as lipo?
My budget is not very high and I believe I can rule out 48v, it's more power than I need I think. I dont need a top speed over 25mph, esp on a dahon i feel it would be very unstable. i wont be commuting or anything. The only situation I might see myself using a 48v is if I decided i want to go trail ridng or something and it would last me 10 miles worth of dirts and hills. But I'm not really planning on that, particularly on the Dahon so maybe 36v or 24v would be fine. The AH, V, all that stuff is so confusing.
Where is the cheapest place I can get a battery? I've looked on ebay and it looks like a 36v 12AH or something similar is around $400. I'd like to try to spend $200-250 if possible. I am also seeing that 36v 8ah is rated higher than 24v 10ah. I dont get this.
The ejoe ebike has a 36v 7ah battery and is rated at 20 miles @ 15 mph weighing at 37lbs. That seems like that would be plenty for my needs so if I got a 36v 8ah-36v10ah or a 24v12ah wouldn't that be enough?
What would be the best battery rating I could afford at $200-250?

I am looking at the hub motors on goldenmotor.com as well as other websites. I will go with geared for sure being that it will be easier to pedal. Maybe 350w motor would be also fine too.

Here is the Ejoe ebike I am referring to; http://www.ebay.com/itm/EJOE-Epik-Compact-Folding-Electric-Bike-Black-/200934657120

I read too fast, and missed where you actually picked out a Dahon.

I would say the best bet is to get a rear motor. Next step is to figure out which will fit at all, if you have less than 135 mm dropouts. You might have to use a single speed to make it fit. But saving the weight of a couple gears won't help anything. Yes weight matters, but a few ounces doesn't matter so much. You will need to stay light to lift that thing into the trunk. Figure on removing the battery to make it lighter for that, and pick a smaller motor rather than a large heavy direct drive motor.

When buying a battery, just ignore everything every seller has to say about how far you can go. With pedaling, range is infinite theoretically. So they just say anything. I have found that for sizing a battery, 1 ah per mile when using 36v is a good starting point. You will go farther, but not in all weather, or all terrain. But that gives you a good idea what is typical for riding 20-25 mph and not pedaling that much at all.

Once you select a motor, you can determine if the kit's controller needs a big battery or a small one. Again, wattage ratings like range ratings are all over the place. Ideally find out what the controllers amps limit is. Then select a battery able to provide that amps, without it being battery murder.

You should be able to find a relatively low power kit, say 15 amps, which will allow the use of more affordable smaller batteries. A 20 amps kit generally takes 12-15 ah size to run it and last a decent time.

Chemistry. Lifepo4, lico (RC batteries), and limn are all lithium polymer types. The currently popular chemistry for bikes is limn or variations of limn. These are not as volatile as the lico. So that's what is in most of the water bottle type batteries.

ridiqls said:

Question: …Reducing weight will increase the range on the bike.

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Reduced weight will not affect steady-speed range significantly. Reduced weight will increase the range if you are doing a lot of stop and start riding, proportional to the amount of stop and starts.

In terms of energy and power, weight should be considered as a percentage of [rider+bike]. In this context a bike that weighs half as much doesn't equate to twice the benefit. Body weight dominates the equation. Benefits from reduced bicycle weight are slim to begin with and progressively less beneficial. Lightweight is over-hyped for pedal bikes and means even less with electrically assisted bikes.

Your investment is better spent on batteries rather than fu-fu lightweight.

i would build one
most of the built ones suck- there are a few good ones like the a2b but they are expensive and aren't that good

ridiqls;

this is a lifep04 battery cell, it is a 6s give about 19.8v cost around $70 for 4.5a, 4 of these will give you 39.6v @9a for about $280. this could get you to putt putt around, giving you an idea if this is enough or you need more. Only draw back is the charger cost. maybe someone can should you how to bulk charge, which would be cheaper than a balance charger. anyway, Hobby King has been a favorite among us ebikers here, I believe. they are cheaper and a warehouse located in USA so delivery is quicker than overseas. Look around their site, lotsa stuff.

http://www.hobbyking.com/hobbyking/store/__10311__Turnigy_4500mAh_6S2P_30C_LiFePo4_Pack.html

the above is for Lifepo4, for a comparable Lipo, it is about $80 cheaper overall and the battery would come about 49v @10a, smaller and lighter size and weight.I think about 50% smaller in size. just a thought.

You will need to connect these battery cells together. Two sets of two 6s batteries connected paralell and then the two set connected in series, this will give you about 40v@9a Lifepo4. Hope this doesnt confuse you.

Jerry

ridiqls;

this is a lifep04 battery cell, it is a 6s give about 19.8v cost around $70 for 4.5a, 4 of these will give you 39.6v @9a for about $280. this could get you to putt putt around, giving you an idea if this is enough or you need more. Only draw back is the charger cost. maybe someone can should you how to bulk charge, which would be cheaper than a balance charger. anyway, Hobby King has been a favorite among us ebikers here, I believe. they are cheaper and a warehouse located in USA so delivery is quicker than overseas. Look around their site, lotsa stuff.

http://www.hobbyking.com/hobbyking/store/__10311__Turnigy_4500mAh_6S2P_30C_LiFePo4_Pack.html

the above is for Lifepo4, for a comparable Lipo, it is about $80 cheaper overall and the battery would come about 49v @10a, smaller and lighter size and weight.I think about 50% smaller in size. just a thought.

You will need to connect these battery cells together. Two sets of two 6s batteries connected paralell and then the two set connected in series, this will give you about 40v@9a Lifepo4. Hope this doesnt confuse you.

Jerry

chisixer6 said:

ridiqls;

this is a lifep04 battery cell, it is a 6s give about 19.8v cost around $70 for 4.5a, 4 of these will give you 39.6v @9a for about $280. this could get you to putt putt around, giving you an idea if this is enough or you need more. Only draw back is the charger cost. maybe someone can should you how to bulk charge, which would be cheaper than a balance charger. anyway, Hobby King has been a favorite among us ebikers here, I believe. they are cheaper and a warehouse located in USA so delivery is quicker than overseas. Look around their site, lotsa stuff.

http://www.hobbyking.com/hobbyking/store/__10311__Turnigy_4500mAh_6S2P_30C_LiFePo4_Pack.html

the above is for Lifepo4, for a comparable Lipo, it is about $80 cheaper overall and the battery would come about 49v @10a, smaller and lighter size and weight.I think about 50% smaller in size. just a thought.

You will need to connect these battery cells together. Two sets of two 6s batteries connected paralell and then the two set connected in series, this will give you about 40v@9a Lifepo4. Hope this doesnt confuse you.

Jerry

Click to expand...

That's not bad, at $280. I'll update when I figure out which one I am deciding on. I am going to do more research when I have time next week. Thanks!!