Help with my first build!

[nippleripple2]

OK, so I’m trying to build my first E bike and I do not know a whole lot about this so please be gentle with me. My first initial thought was to get a nice sturdy, hard tail mountain bike ( 26 or 27 inch) and then I was going to buy some sort of kit that I see all over Amazon, Walmart, eBay, etc. I currently have a 20 inch Fat tire bike and it’s just way too heavy to get up and down the stairs it slow and even more difficult to maneuver on the road. There’s not a whole lot of information online about how fast some of these motors can go or what they’re able to except as far as continuous current amps, I would like to be able to go at least high 30s possibly 40s I don’t have many hills per say however, there are some slopes in my area plus I’m also about 200 pounds so I really would like a decent amount of torque. is it really necessary to get a 72 V battery? or could I use a 52 V or even 60 V to achieve what I’m looking for? Anyone that could help with a specific kit as well as battery that would be easy to connect with that kid I’d like to stay away from major wiring, understanding that some will be needed. I’ve looked online for hours and hours and I’m so stuck on where to go or what to get really would just like someone to help me out and give me specific information on what type of kit and battery I can get that would be best for my needs. I’m also trying to stay around a $500 budget not including the bike

 

[6zfshdb]

Welcome to the forum!
A good place to start is Grin Tech in Vancouver:

Start Here - Getting Started

This is a landing page for people who are relatively fresh to DIY ebikes and are thinking about doing a conversion. It outlines what the conversion process entails, and provides multiple links to different parts of our website that you really should read and understand before contacting Grin...

ebikes.ca

They also sell a variety of quality built kits & batteries. Once you get into it, you'll likely have many specific questions that can be answered by using the forum search function. If not, by all means, ask questions specific to the task at hand. Pictures are also a great help.

Good luck with your build!

 

[gromike]

If you're planning on building a high speed ebike the Endless Sphere forum would be a better site for that kind of build.

 

[nippleripple2]

Welcome to the forum!
A good place to start is Grin Tech in Vancouver:

Start Here - Getting Started

This is a landing page for people who are relatively fresh to DIY ebikes and are thinking about doing a conversion. It outlines what the conversion process entails, and provides multiple links to different parts of our website that you really should read and understand before contacting Grin...

ebikes.ca

They also sell a variety of quality built kits & batteries. Once you get into it, you'll likely have many specific questions that can be answered by using the forum search function. If not, by all means, ask questions specific to the task at hand. Pictures are also a great help.

Good luck with your build!

Awesome I really appreciate the reply and information. I thank you,!

 

[RunForTheHills]

A hardtail MTN bike is a good choice. I would get a kit from a reputable vendor that offers support since it is your first build rather than a cheap Chinese kit. Hub motor kits work well on flat ground and moderate hills, but if you are doing long steep hills then a mid-drive would be a better choice as it can use the gears of the bike to reduce the torque required by the motor and will be less likely to overheat. The Grin kits above are great and I have two of them, but they are also on the pricier side. Grin also doesn't sell mid-drive kits, just hub motors.

MTA: Voltage isn't important to torque. higher voltage for the same winding on a motor will result in faster speeds. I think 52V is the sweet spot, but you can build a reliable bike at any voltage. Lower voltages will pull more current from the battery for the same wattage, so you need thicker wires and a battery that can handle higher currents for higher wattage builds.

 

[RunForTheHills]

I missed the part about going high 30's or 40's. You won't be able to go that fast with a cheap kit and it won't be safe on a cheap bike. You are essentially building an emotorcycle. At speeds above 25mph, wind resistance becomes the dominant force you have to overcome and it increases exponentially. You also won't be able to contribute much by pedaling above the high 20's because the gearing on the bike will spin out. I would advise you to lower your expectations for the bike to the low 30's or visit Endless Sphere as recommended above for how to build a fast ebike.

 

[Elyot919]

High 30s / 40s on a $500 kit just isn’t realistic or safe. That’s e-moto territory, not casual conversion. If you dial expectations back to low 30s, things get way simpler and cheaper.

 

[harryS]

OK, you already have a 20" fat tire ebike, and think it's too slow? Probably goes 24 mph? By the way, you're lucky if it goes that fast.

And you still want to go faster? Well, I've always heard that the 1500W direct drive motors like the Voilamarts can get past 30 mph pretty easily on 48V. Your current battery might be able to supply the 30 amps needed for that.

By definition, high speed ebiking is a death trap on most any bicycle, Do put the motor on the rear. If you put it up front, it's a death wish for sure. The forks often break with a motor in them and will faceplant you.

While I've never seen one, I figure there must be tens of thousands of these 30+ mph DIY bikes on the road and no reports of mass carnage. So have fun and be careful,

 

[RunForTheHills]

There are more than a few out there. The argument usually made is by commuters that think car drivers will be less likely to try to kill them if they can keep up with traffic and their commute will take ten minutes less time. I think car drivers are still going to resent that a bicycle is in the lane in front of them and even a 40mph bike can't really keep up with car traffic. Plus if you are going that fast, it is going to drain your battery just to overcome the wind resistance. So you need a really big (expensive) battery, disc brakes, good suspension so the potholes won't kill you, an expensive controller, and a motor that can put out 2000 - 3000+ watts of power. Plus some safety gear for yourself in case you do have to lay the bike down at high speed. Not a cheap build if you do it right and not street legal unless you register it as a moped. Which people do.

 

[kevinmccune]

OK, you already have a 20" fat tire ebike, and think it's too slow? Probably goes 24 mph? By the way, you're lucky if it goes that fast.

And you still want to go faster? Well, I've always heard that the 1500W direct drive motors like the Voilamarts can get past 30 mph pretty easily on 48V. Your current battery might be able to supply the 30 amps needed for that.

By definition, high speed ebiking is a death trap on most any bicycle, Do put the motor on the rear. If you put it up front, it's a death wish for sure. The forks often break with a motor in them and will faceplant you.
Ed and violamart
While I've never seen one, I figure there must be tens of thousands of these 30+ mph DIY bikes on the road and no reports of mass carnage. So have fun and be careful,

they will and they might be a bit hard on the battery,hard to pedal bur surprisingly torquey,grabbed an old violamart conversion that had a 10 ah battery sitting all last winter cracked the throttle and it almost shot out of my hands(wasn't expecting the wheelie)

 

[PedalUma]

@nippleripple2, See the thread Clean Custom Conversions.