DIY inquiry from those with homebuilt e-bikes

Thank you, then current is what I set in my BBS01 controller? So peak power at highest PAS setting would be 18A for me. The Time-Current characteristic curves in the chart Gionnirocket posted suggest as long as I just quickly press and don't lean on the horn button a 4A fuse could handle it. Somewhere I have one of those Wuxing big green buttons but as it has a Higo yellow connector I don't think I could just cut off the connector as I need two wires not three.
Don't confuse phase current to the motor with the battery current to the accessories. The motor controller will not regulate the current to the horn. The horn linked below says that it will pull 1.5A. This is well under the 4A rating of the fuse and the fuse won't blow no matter how long you push the button. If the wire were to get shorted to ground, it creates an unsafe condition that would pull a lot more than 4A and possibly damage components or cause a fire. The short would cause the fuse to blow.

https://www.amazon.com/ROOTS-CTSH36-48H-Horn-1-5AMP/dp/B084KW49HV
 
Lot of excellent feedback. Wondering if anyone commenting can post a image of the e-bike they built. Photo reference is always very helpful.
 
Thanks that looks simple enough, I'd read given the 36v current from my battery it would be good to wire in a fuse as Gionnirocket suggests
I have 21 amps running through those wires, plus the internal wires in the horn are even thinner than the 24 guage connecting wires.
If I put a 4a fuse in it would blow every time I need a horn !. Worst case, without a fuse, the horn wires would melt and you would have to re wire it.
 
I've built two hub motor bikes. The first was a failure because both LIFePo4 batteries I bought had internal bad welds. Neither would supply >50 W. I had the 18 lb battery mounted to the front torque arms (28") and hung from the handlebars, and steering that much weight was a problem on my rutted summer camp driveway. I abandoned that Huffy Savannah frame as an electric project.
The current yubabike bodaboda, shown left, has holes cast in the frame to hang a front basket from. I hung the battery up there. The front hub motor is cut off from my picture by the avatar edit software. I have about 7500 miles on the bike 6500 powered. I initially installed a 1000 W DD hub motor ($189) to prove the $630 luna battery was good. I didn't like the unpowered drag of that motor since I ride unpowered about 80% of the distance. I brought the ebikeling power wheel with geared hub motor into town from the summer camp where the Savannah was converted. I enjoyed that motor for 4500 miles until the gears wore out. $221 down, on to the next. Found a Mac12T in a front wheel at lunabike with controller & throttle for $730. 2000 miles down on that motor. Original luna battery going fine for 3 1/2 years.
I don't want a mid drive bike. I cross 80 hills in my 30 mile commute to summer camp, the hub motors handled that fine. Front drive works fine with my weight on the front wheel. I don't power across wet or muddy steel plates (frequent) wet rock (rare) wet wood bridge decks (rare) or ice (seasonal). The 14 lb on the front balances the 10 lb of tools & water I carry always in the back panniers. I also carry 60 lb of supplies frequently and occasionally 80 lb. I don't drive anymore except U-hauls for heavy loads.
I don't want to power up to 30 mph. I want to power into a 25 mph headwind for 30 miles at 10 mph, same speed as I ride unpowered without a strong headwind. No power, 30 miles took 6 hours a hot windy September day in 2018. 144 bpm the whole day. I don't need that much exercise. I peak at 35 mph at the bottom of some hills, the ones with no rocks potholes or mud at the bottom.
My lights are independently powered, two with MicroUSB charge port and two with internal batteries (AAA). Usually not both front or rear will be dead. I have no horn.
No more pictures. That camera was stolen and I don't like Pres. Xi enough to buy another. No other source of anything electronic.
 
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I have 21 amps running through those wires, plus the internal wires in the horn are even thinner than the 24 guage connecting wires.
If I put a 4a fuse in it would blow every time I need a horn !. Worst case, without a fuse, the horn wires would melt and you would have to re wire it.
The trick is to put the 4A fuse inline with just the horn and not the motor. Install it on the positive 24 gauge wire connecting the horn to the battery. It takes about 29-30A to melt 24 gauge copper wire. Your call.
 
The trick is to put the 4A fuse inline with just the horn and not the motor. Install it on the positive 24 gauge wire connecting the horn to the battery. It takes about 29-30A to melt 24 gauge copper wire. Your call.
Understood, thanks, but the internal wires are like 1 strand of wire, I don't even know what they would be rated at but the wire is not much bigger than a fuse wire.
 
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Why is it that everyone that hasn't built an eBike... but wants to, has a totally unrealistic concept of what they want to build? The reality is that you will buy a kit or parts, it will go 28 mph to possibly 30 mph and you'll get about 34 miles out of a charge. Plus, the battery will be pretty darn big and might not fit in a full-suspension bike frame.

Here's the thing... get a kit and a donor bike, build it, ride it and have a blast. You'll find that 28 mph is fast enough for riding on the flat. You'll find after about 25 miles that you are getting kind of tired and you don't need a 100 mile range.

I say this because, if you set unrealistic goals it will only keep you from building and enjoying your DIY eBike.

Yes, I built my own bike. It goes 28 mph. It can go a bit over 30 miles on a charge, but I'm usually tired before it runs out of juice. And, it's a blast to ride.

PS. Everyone here likes to suggest Luna and Grin... but there are plenty of others out there that are worth looking at.
 
Lot of excellent feedback. Wondering if anyone commenting can post a image of the e-bike they built. Photo reference is always very helpful.
Here are some of mine. And yes I went all out to go dig up pics :D. Most of these I still have and ride. I have seven atm and am looking to sell the white one and just finished prepping the top left cargo bike for sale. Just need to do a photo shoot and put it up on Facebook Marketplace.
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PS. Everyone here likes to suggest Luna and Grin... but there are plenty of others out there that are worth looking at.
Yeah but for example Luna's price on a bare bones motor-only BBSHD is about $100 less than the other reliable vendors on the market. And I know what I am getting insofar as firmware quirks or lack thereof.

There are so many kaka places to go to buy stuff that you recommend safer places if you've been there/done that successfully. You want the new guy to succeed too.
 
Here are some of mine. And yes I went all out to go dig up pics :D. Most of these I still have and ride. I have seven atm and am looking to sell the white one and just finished prepping the the top left cargo bike for sale. Just need to do a photo shoot and put it up on Facebook Marketplace.
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LOL when I saw that giant green bean of a thing !
 
Why is it that everyone that hasn't built an eBike... but wants to, has a totally unrealistic concept of what they want to build? The reality is that you will buy a kit or parts, it will go 28 mph to possibly 30 mph and you'll get about 34 miles out of a charge. Plus, the battery will be pretty darn big and might not fit in a full-suspension bike frame.

Here's the thing... get a kit and a donor bike, build it, ride it and have a blast. You'll find that 28 mph is fast enough for riding on the flat. You'll find after about 25 miles that you are getting kind of tired and you don't need a 100 mile range.

I say this because, if you set unrealistic goals it will only keep you from building and enjoying your DIY eBike.

Yes, I built my own bike. It goes 28 mph. It can go a bit over 30 miles on a charge, but I'm usually tired before it runs out of juice. And, it's a blast to ride.

PS. Everyone here likes to suggest Luna and Grin... but there are plenty of others out there that are worth looking at.
I think you can replace a lot of your "you"s with "I"s :)
 
LOL when I saw that giant green bean of a thing !
That sucker is more than 8 feet long :) I rode it into work today, and when I do it again tomorrow I'll detour across town to Costco tomorrow before I head back home. Has a 32ah battery boxed in under the floor. You take the convenience of the storage capacity for granted just like you take for granted having a back seat and a trunk on your car. A for reals automobile replacement.
 
Actually, I was only responding to the OP's "motor system has to be in the lower 30's mph, No throttle assist. Battery capacity range from 50 min - 120 miles max"
The thing is, you made a lot of "you" statements when it would be more correct to make them "I"statements. For example,
"you'll get about 34 miles out of a charge."
"You'll find that 28 mph is fast enough for riding on the flat."
"You'll find after about 25 miles that you are getting kind of tired and you don't need a 100 mile range.
 
That sucker is more than 8 feet long :) I rode it into work today, and when I do it again tomorrow I'll detour across town to Costco tomorrow before I head back home. Has a 32ah battery boxed in under the floor. You take the convenience of the storage capacity for granted just like you take for granted having a back seat and a trunk on your car. A for reals automobile replacement.
Next step for electric automobile replacement...
1000 mile range, solar powered, 0 to 60 in 3.5 sec ! 40 miles of free solar range every day. $25 to 30k minus gov incentives.
 
Lot of excellent feedback. Wondering if anyone commenting can post a image of the e-bike they built. Photo reference is always very helpful.
Hi Alanzo, here is a blog post with pictures I wrote this spring about my DIY conversion
 
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Actually, I was only responding to the OP's "motor system has to be in the lower 30's mph, No throttle assist. Battery capacity range from 50 min - 120 miles max"
Its for a personal goal. I like the concept of using batteries and a motor to surpass what I did at an earlier time in life.
 
Here are some of mine. And yes I went all out to go dig up pics :D. Most of these I still have and ride. I have seven atm and am looking to sell the white one and just finished prepping the the top left cargo bike for sale. Just need to do a photo shoot and put it up on Facebook Marketplace.
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BEAUTIFUL!!! Is the 7th photo with partial blue paint a frame you fabricated? I recall seeing this bike previously in another thread and thought it to be the most amazing e-bike that can carry a lot of weight for a long distance self supported tour. Never saw anything like it previously. I love your fat tire bikes as there is no limit to the riding terrain. What I have in mind is closer to the bikes in your 3rd & 4th photos. Dual suspension with a wheelset to allow for tire choices with low rolling resistance for pavement. The yellow bike in your last photo appears to be a hardtail but not sure from the small size in the image.

When you have time available can you share any additional photos close up of the motor systems you have on some your bikes and provide a brief explanation of how you secured the motor to the frame including any techniques you developed to solve potential installation issues of a component not fitting or in need of reinforcement. Best way I can learn and get started is to see what others have successfully accomplished with detailed photos.
 
BEAUTIFUL!!! Is the 7th photo with partial blue paint a frame you fabricated? I recall seeing this bike previously in another thread and thought it to be the most amazing e-bike that can carry a lot of weight for a long distance self supported tour. Never saw anything like it previously. I love your fat tire bikes as there is no limit to the riding terrain. What I have in mind is closer to the bikes in your 3rd & 4th photos. Dual suspension with a wheelset to allow for tire choices with low rolling resistance for pavement. The yellow bike in your last photo appears to be a hardtail but not sure from the small size in the image.

When you have time available can you share any additional photos close up of the motor systems you have on some your bikes and provide a brief explanation of how you secured the motor to the frame including any techniques you developed to solve potential installation issues of a component not fitting or in need of reinforcement. Best way I can learn and get started is to see what others have successfully accomplished with detailed photos.
The blue bike is a Surly Big Fat Dummy in what they call 'bliolet'. What you see there actually started out as a complete bike and I ended up completely stripping it down and replacing everything but the headset and the rear derailleur, plus adding on bits I did fabricate like the wideloaders, which are used to carry enormous loads (560 lbs total system weight is my max and lemme tell ya... you don't want to go there; its too much for the frame and for a safe ride. I did it by accident).

As for details on it, look back to Post #5 in this thread. I gave you a link to my site and I have done build writeups on most of these bikes, where I felt it was warranted. You will find I have described the BBSHD motor mounting in some level of detail. There are two ways I do it. One is two inner lock rings torqued to 100 ft lbs each. I am certain I've documented that. Nothing more is needed and it never shifts. Earlier, I also used a dual hose clamp setup, with its use disguised via black shrinkwrap over the motor's clamp and a color coordinated shrinkwrap over the one on the down tube. The last three BBSHD'd bikes I have built do not use the hose clamp thing because the dual lock rings have proven to be sufficient.

Click any image to embiggen.
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You may need to oversize your motor and use spacers to take up any slack. Here are two examples.

Look down at this motor on the drive side. See how there is a fat spacer behind the secondary gear housing? McMaster-Carr will sell you a custom made metric bushing to your specs for about $40. I reduced the inner diameter about a half millimeter from a standard bottom bracket spacer, and added to the outside diameter by a couple more millimeters to make for a rock solid purchase with no wiggling. Length was tailored to let the 120mm-axle'd motor perfectly clear the 5" chainstays. This was required to fit the motor onto that fat frame even though the bottom bracket was 'only' 100mm. The second pic beside it shows a test-fit on my ti bike using standard bottom bracket spacers and washers I needed some on both sides, and note on the non drive side the spacer goes OUTSIDE trhe clamping plate. I ended up doing the same kind of custom bushing for a drive side spacer and found a 10mm steel spacer on AliExpress for the non drive side.
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A Cyc X1 is pretty similar to a Cyclone, which is kind of the grandpa of the Cyc. The Cyc needs no reinforcement, and if you look at the pic below you can see I used two industrial strength zip ties to snug it to the frame. The Cyc factory supplied a cloth strap at the time which was ridiculous. Nowadays they provide a metal strip of some sort.

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For a Cyclone, its a similar issue except the motor mount is in fact insufficiently strong and it flexes. You need to cross-brace the hell out of it or fabricate a replacement. I used an arrangement of extra-long bolts in between the two arms, under the frame, set up as standoffs to stop it from flexing under throttle. This is a common problem with that motor and myriad solutions are on display over at Endless Sphere. The Cyclone uses the hose-clamp+giant zip tie method to clamp to the down tube. I did a full tutorial on Cyclone installation over at electricbike.com although when I wrote that I hadn't sussed out the need for the reinforcement. If you go the Cyclone route, do a full size one. A good place to go for them and their various bits is Sick Bike Parts as well as Luna. BUT: a Cyclone should not be your first build. I think my tutorial still is the only one out there and in addition to the community seemingly wanting to keep how you set one up a secret, the motors are powerful but unrefined.


IK have only a few photos of my poor Stumpjumper, which I resurrected a corner of my garage. During its shakedown cruises an inattentive motorist t-boned me while I was in the bike lane. 15 mph and 3 separate headlights: A SMIDSY accident. Bike was destroyed and after the other driver's insurance company paid me for the bike I donated the motor to someone in need.

The yellow bike: 'Frankenbike' was made from a fresh frame which I stripped, primed and painted MFP Yellow (google that), with all of the remaining parts except the handlebars being take-offs from other bikes that I had upgraded over the previous years. It is the same alloy fat frame as the purple bike. I bought both frames from Kyle Chittock @ Bolton ebikes. They were discounted as his frame supplier had misspelled his company name on the bikes so he couldn't use them on what he was building in-house at the time. Rear hub is a leftover Sondors-originated 350w Bafang G060 geared hub. 48v bottle battery and 25a controller.
 
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