Looking to build a bike

General Discussion about electric bicycles.
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jerkface38   10 µW

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Looking to build a bike

Post by jerkface38 » Oct 03 2019 10:34pm

Hi guys, this is my first time here. I browse some of the forum and have decided that I am definitely interested in building a bike. I plan on using it as a daily driver and leaving my car in my driveway most of the time.

Purpose: Daily Commute so I can ditch my car commute and save money
Distance: 3 Miles each way, can't charge at work because it's against policy
Desired trip time: 5-8 minutes
Desired Cruising Speed: 35-45 MPH but will likely go slower for safety reasons
How hard I want to pedal: Not much, only when I want to exercise
Weight: 165-170 lbs 6'
Location: Sacramento
Terrain: Some offroad bike trail, sometimes a little mud and dirt, mostly flat road, biggest incline is about 50 feet.
Budget: As close to 1500-2500 as I can get
Motor Type: Rear Hub Motor or Mid Drive

I plan on either using the vector bike frame or the futr bike frame. If I don't use one of those I might even go with a custom bike frame built by the shop across from where I work. He mostly does motorcycles but I talked to him and he said he would do a bike for me if I want. Not sure how much that would cost though so it might be something I do in the future when I've saved a bit more.

I plan on building the battery pack myself. I will probably go with a 52v 20ah build to start. I'm not too sure of anything else. I looked for gear boxes and can't seem to find any for sale I'm not sure if I even need them. I'm really not sure if I should go with a mid drive or a rear hub motor but I'm sure you guys will give me plenty of opinions. Let me know what you think and thank you for any advice.

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travaglione   10 µW

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Re: Looking to build a bike

Post by travaglione » Oct 04 2019 2:56am

I have been ride my e-bike for about a year now. I love using it. It gets me on my bike more often. I like not buying as much gas. I like the exercise i get . I like the hub motor because as i age and with deep snow and ice in the winter i would like to build a tadpole trike and just switch the rear wheel and other components for the season change . I decided not to build a battery because of the little difference in cost when just building one battery and for safety reasons. My job as changed since I started my build so my commute as change from 8 blocks to 5 miles. I love having extra battery Amp hours. I had problems with a used Bionx system and have been happy with the performance of Grin products. hope this helps
Broken Bionx Trek Valencia added
Crystalyte M3540 and Phaserunner controller, 12 LIGO Batteries

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E-HP   100 kW

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Re: Looking to build a bike

Post by E-HP » Oct 04 2019 9:20am

jerkface38 wrote:
Oct 03 2019 10:34pm
Desired Cruising Speed: 35-45 MPH but will likely go slower for safety reasons
How hard I want to pedal: Not much, only when I want to exercise
Weight: 165-170 lbs 6'

I plan on either using the vector bike frame or the futr bike frame. If I don't use one of those I might even go with a custom bike frame built by the shop across from where I work.

I will probably go with a 52v 20ah build to start.
Your choice of frames will limit the choices of motors, due to the drop out widths, so you'll need to decide on one or the other. Those frames will fit big motors, with big power demands.

Ignoring the drop out criteria for a moment, I don't think your battery will get you there; you'll likely need to go to a 72 volt battery, even with a less power thirsty motor. You can play with the Grin motor simulator, and set the controller to something high so it won't be the bottleneck, and the battery to your desired voltage and capacity, then test various motors. You want fast wind motors, and since Sacramento is dead flat, you don't need to adjust grades in the simulator.

Here's an A/B comparison of the fast turn Leaf motor at 52 and 72 volts, approximating your total weight at 220, no grade. You can select different motors to see what you get, but pay attention to the bottom section that tells you whether the motor will melt and after how long.

https://www.ebikes.ca/tools/simulator.h ... bopen=true

Welcome to the forum, by the way. :thumb:

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thundercamel   1 kW

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Re: Looking to build a bike

Post by thundercamel » Oct 04 2019 10:17am

I agree with the 72v battery if you want 40+mph. Your link was for the 5 turn Leaf motor (Grin's default), and here is a link with the 4 turn (Leaf's default config) rpm/v numbers pasted in:
https://www.ebikes.ca/tools/simulator.h ... kv_b=13.16

Helps a little bit for speed. The Vector and Futr bike frames are pretty serious for a 3 mile commute :) Don't they use a 20" rear wheel? In that case, the fast wind motor and higher voltage battery will matter even more. I personally view direct drive hub motors as the most reliable, but admit I haven't tried a mid-drive, like the Cyclone 3 kilowatt.
My Ebike builds - Existing bikes, affordable motor kits, self built 14s6p batteries - Now with more recumbent!

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Re: Looking to build a bike

Post by Grantmac » Oct 04 2019 10:54am

For a commute that short I'd look for a high drain pouch cells and run high volts.

I personally like mid-drives and the Lightning Rods big block is a nice option to get the performance you're after.

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E-HP   100 kW

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Re: Looking to build a bike

Post by E-HP » Oct 04 2019 11:15am

thundercamel wrote:
Oct 04 2019 10:17am
I personally view direct drive hub motors as the most reliable, but admit I haven't tried a mid-drive, like the Cyclone 3 kilowatt.
On flat terrain combined with not wanting to pedal, direct drive is probably the way to go. You can ride all day and never have to shift (or pedal to shift).

jerkface38   10 µW

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Re: Looking to build a bike

Post by jerkface38 » Oct 04 2019 4:10pm

Grantmac wrote:
Oct 04 2019 10:54am
For a commute that short I'd look for a high drain pouch cells and run high volts.

I personally like mid-drives and the Lightning Rods big block is a nice option to get the performance you're after.
The commute is short but I also intend to use it to see family and friends who are 10+ miles out. I'm basically going to be using it for everything including grocery shopping within a short distance.

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E-HP   100 kW

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Re: Looking to build a bike

Post by E-HP » Oct 04 2019 4:25pm

jerkface38 wrote:
Oct 04 2019 4:10pm
I'm basically going to be using it for everything including grocery shopping within a short distance.
Are you adding a rack?

jerkface38   10 µW

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Re: Looking to build a bike

Post by jerkface38 » Oct 04 2019 4:35pm

thundercamel wrote:
Oct 04 2019 10:17am
I agree with the 72v battery if you want 40+mph. Your link was for the 5 turn Leaf motor (Grin's default), and here is a link with the 4 turn (Leaf's default config) rpm/v numbers pasted in:
https://www.ebikes.ca/tools/simulator.h ... kv_b=13.16

Helps a little bit for speed. The Vector and Futr bike frames are pretty serious for a 3 mile commute :) Don't they use a 20" rear wheel? In that case, the fast wind motor and higher voltage battery will matter even more. I personally view direct drive hub motors as the most reliable, but admit I haven't tried a mid-drive, like the Cyclone 3 kilowatt.
The commute is 3 miles but I plan on riding it everywhere. Even with my three mile commute I'm still spending $80-$120 a month in gas for my Corolla. I'm open to opinions on bike frames as well, only picked those because they seem a lot sturdier than the rest and I want it to last a long time since I'm basically getting it for $275 off through my credit card bonuses after I hit $1,000. I believe the site said that it can go up to a 26" or 27.5" wheel (would need to look again).

I'm going to look into the leaf Motors. I really don't know a whole lot about this stuff but I feel I've learned quite a bit in just this last week. I feel that by the time the malectrics spot welder gets here I'll have confidence in building a 52v battery. I'm still not sure how long before I'll feel safe building a 72v battery. You guys have been a big help already so thanks for that.

I'll be looking into high drain pouch cells but I also want something that has a moderate duration of charge. Also need to figure out the regenerative braking system. Also I'm wondering if direct drive is the same thing as mid-drive or if they're different things? Edit: just looked into it. They are definitely different things. I'm used to just calling them front and rear hub motors :lol:
E-HP wrote:
Oct 04 2019 4:25pm
jerkface38 wrote:
Oct 04 2019 4:10pm
I'm basically going to be using it for everything including grocery shopping within a short distance.
Are you adding a rack?
Probably not, just going to use my backpack. Might look into adding a rack in the future but it's likely not going to be necessary.

RunForTheHills   100 W

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Re: Looking to build a bike

Post by RunForTheHills » Oct 04 2019 8:26pm

3 miles at 20 MPH average will take you 9 minutes. 3 miles at 40 MPH will take you 4 1/2 minutes. Stop signs and lights could add a few minutes to that. You don't need a 45 MPH bike for a 3 mile commute. A 20 MPH bike can easily be built for under $2000. A safe 45 MPH bike, not so much. To build the 20-25 MPH bike, just buy a used mountain bike on Craigslist and buy a motor kit and battery from EM3EV or buy a cheap DD kit on eBay and buy the battery from a reputable source.

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motomech   1 GW

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Re: Looking to build a bike

Post by motomech » Oct 05 2019 1:15am

The commute is 3 miles but I plan on riding it everywhere. Even with my three mile commute I'm still spending $80-$120 a month in gas for my Corolla.
Although your proposed build sounds like fun, one doesn't build a custom 40 - 45 mph ebike to save money.
Maybe if you were to build a more commute appropriate 20 to 25 mph assist ebike w/ a simple hub motor and a 48 Volt pack, you could see a savings after a while.
Really, if economy were your true goal, you could buy a new Chinese scooter or sm. motorcycle for less $$ that a 45 mph ebike will end up costing over time. At 30 miles a week @ 75 mpg,....well, you get the math. And no constant fussing and fiddling that an ebike requires.
Motomech


'07 GT Idive 4 4.0, Q100H 201 frt. mounted, 14S Multistar LiPoly, elifebike 9-FET 20A controller. Mean Well HLG-320H-54A, Crazy Bobs on Alex DM32's 21 to 22 MPH. viewtopic.php?f=3&t=28151&p=1373714&hilit=Idrive#p13737

flat tire   1 MW

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Re: Looking to build a bike

Post by flat tire » Oct 05 2019 1:28am

motomech wrote:
Oct 05 2019 1:15am
\
Although your proposed build sounds like fun, one doesn't build a custom 40 - 45 mph ebike to save money.
Bingo. If saving $1000 a year on gas is a big deal you are barking up the wrong tree with an ebike that goes 45+ for any distance with any reliability.

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wturber   10 MW

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Re: Looking to build a bike

Post by wturber » Oct 05 2019 9:48am

As a general rule, you don't build an ebike to save money. You might end up saving money in the long haul, but if you don't totally ditch the car and insurance, you won't save much. If you really want a car replacement bike, I think you need a long or medium tail that will allow you some space to build some cargo carrying capacity. Look up longtail on this forum for ideas. Use a rear DVD motor and understand that this bike won't like trail riding much. You could easily build it for 35 MPhil or so without getting to exotic but for general purpose riding, 25 MPhil is often plenty and will extend your range a lot,

$100 a month on Gas suggest about 750 miles a month driven. You can do that with an ebike, but you'll really want a comfortable and versatile bike.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
8 x 36v 4.3ah 10s 2P battery packs - 1500W 30A DC Boost Converter delivers 54v and about 1000 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
viewtopic.php?f=2&t=90369

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wturber   10 MW

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Re: Looking to build a bike

Post by wturber » Oct 05 2019 10:10am

Consider a long or mid tail cargo bike if you really want to replace a car.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
8 x 36v 4.3ah 10s 2P battery packs - 1500W 30A DC Boost Converter delivers 54v and about 1000 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
viewtopic.php?f=2&t=90369

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E-HP   100 kW

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Re: Looking to build a bike

Post by E-HP » Oct 05 2019 11:06am

jerkface38 wrote:
Oct 04 2019 4:35pm
I feel that by the time the malectrics spot welder gets here I'll have confidence in building a 52v battery. I'm still not sure how long before I'll feel safe building a 72v battery.
I don't think there's any inherent differences when it comes to safety between building a 53v or 72v pack. Basically you're just placing the nickel strips in a different configuration so the series strings have more cells. In other words, you can make the same mistakes with a 52v pack as with 72v, and end up with the same big ball of fire.

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Re: Looking to build a bike

Post by Jil » Oct 05 2019 1:45pm

Why do you want a 45 mph cruising speed to ride... 3 miles ?
30 mph will be enough, your bike will be lighter, your battery also, and your ride will be only 2 minutes longer ;)
My bike : Surly "eKrampus" with GMAC 8T, Phaserunner and 20 Ah/52 V Li-ion battery.

jerkface38   10 µW

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Re: Looking to build a bike

Post by jerkface38 » Oct 05 2019 4:00pm

Jil wrote:
Oct 05 2019 1:45pm
Why do you want a 45 mph cruising speed to ride... 3 miles ?
30 mph will be enough, your bike will be lighter, your battery also, and your ride will be only 2 minutes longer ;)
I said previously: The commute is short but I also intend to use it to see family and friends who are 10+ miles out. I'm basically going to be using it for everything including grocery shopping within a short distance.

Its kind of like having an extra oomf just in case or having more space in your house that you dont need but could use if you do. It's the same principle just applied to a vehicle. I just want the option.
E-HP wrote:
Oct 05 2019 11:06am
jerkface38 wrote:
Oct 04 2019 4:35pm
I feel that by the time the malectrics spot welder gets here I'll have confidence in building a 52v battery. I'm still not sure how long before I'll feel safe building a 72v battery.
I don't think there's any inherent differences when it comes to safety between building a 53v or 72v pack. Basically you're just placing the nickel strips in a different configuration so the series strings have more cells. In other words, you can make the same mistakes with a 52v pack as with 72v, and end up with the same big ball of fire.
There really isn't but the difference is I already know how to do 52v and I don't know how to do a 72v triangle configuration yet.
wturber wrote:
Oct 05 2019 9:48am
As a general rule, you don't build an ebike to save money. You might end up saving money in the long haul, but if you don't totally ditch the car and insurance, you won't save much. If you really want a car replacement bike, I think you need a long or medium tail that will allow you some space to build some cargo carrying capacity. Look up longtail on this forum for ideas. Use a rear DVD motor and understand that this bike won't like trail riding much. You could easily build it for 35 MPhil or so without getting to exotic but for general purpose riding, 25 MPhil is often plenty and will extend your range a lot,

$100 a month on Gas suggest about 750 miles a month driven. You can do that with an ebike, but you'll really want a comfortable and versatile bike.
I'm going to be bringing my insurance down to almost nothing which will save me about $100 a month just that. That doesn't include car maintenance and gas. The bike will pay for itself within a year even if I have to tinker with it every now and then. Also I'm planning on renting the car out to someone so I will probably make about $500 a month on it and if they crash it I'll get a nice fat check.
wturber wrote:
Oct 05 2019 10:10am
Consider a long or mid tail cargo bike if you really want to replace a car.
I'll be looking into this as well. Thank you for the tip.
RunForTheHills wrote:
Oct 04 2019 8:26pm
3 miles at 20 MPH average will take you 9 minutes. 3 miles at 40 MPH will take you 4 1/2 minutes. Stop signs and lights could add a few minutes to that. You don't need a 45 MPH bike for a 3 mile commute. A 20 MPH bike can easily be built for under $2000. A safe 45 MPH bike, not so much. To build the 20-25 MPH bike, just buy a used mountain bike on Craigslist and buy a motor kit and battery from EM3EV or buy a cheap DD kit on eBay and buy the battery from a reputable source.
I'm going to be using it for more than just commuting but that is its main purpose. I will look into what you said as a secondary e-bike since I will probably need two just in case anyways. Also I have other goals that require me to have a decent knowledge of making these things. Already read these posts after work.

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Re: Looking to build a bike

Post by RunForTheHills » Oct 05 2019 4:31pm

jerkface38 wrote:
Oct 05 2019 4:00pm
I'm going to be using it for more than just commuting but that is its main purpose. I will look into what you said as a secondary e-bike since I will probably need two just in case anyways. Also I have other goals that require me to have a decent knowledge of making these things. Already read these posts after work.
A second bike sounds like a good plan, but you will definitely blow your budget doing that. The first ebike is going to be a learning experience anyway. Tread carefully renting out your car though. You have liability if you loan out your car and the other driver gets into an accident and your insurer may not cover you if you are renting it out.

https://www.nerdwallet.com/blog/insuran ... insurance/

jerkface38   10 µW

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Re: Looking to build a bike

Post by jerkface38 » Oct 05 2019 7:19pm

RunForTheHills wrote:
Oct 05 2019 4:31pm
jerkface38 wrote:
Oct 05 2019 4:00pm
I'm going to be using it for more than just commuting but that is its main purpose. I will look into what you said as a secondary e-bike since I will probably need two just in case anyways. Also I have other goals that require me to have a decent knowledge of making these things. Already read these posts after work.
A second bike sounds like a good plan, but you will definitely blow your budget doing that. The first ebike is going to be a learning experience anyway. Tread carefully renting out your car though. You have liability if you loan out your car and the other driver gets into an accident and your insurer may not cover you if you are renting it out.

https://www.nerdwallet.com/blog/insuran ... insurance/
Yeah I was just thinking about doing a much cheaper and lighter ebike for the secondary one. He will have his own insurance for the car and I will be keeping track of it. It will be a cash arrangement so there will be no proof that I'm renting it out. It will probably be a 3 to 6 months agreement which will more than pay for the bikes.

I'm going to go with the one stage block big drive from the lightning rod site. I'll start with a 52v battery and then move up from there after I've done some groundwork for the 72v battery battery. I'm going to need a bunch of battery packs for one of my other projects anyways so it's not that big of a deal. Just waiting for my spot welder so I can do it at home.

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