Wife Hopper beach cruiser

maurtis

New Member
Hi all,

For some time now I have been planning out the build for my wife's eBike, using her Huffy Panama Jack beach cruiser. Yes, I know, I really wanted to use a different frame too but she insisted since "it is so cute". She said that if I really wanted to build a bike for her, that I needed to keep it clean and retro. My bike was built for balance and speed, none of these fashion concerns! LOL

So, let the planning begin...

The goal was for a 30 MPH ride that required little to no pedaling, since the neighborhood speed limit is 25 MPH. And a 10 mile range would get her to and from Walgreens, friend's houses, corner store, etc a couple times between charges.

Here is what I ended up going with:
- Huffy Panama Jack beach cruiser
- Front cantilever brake forks from my Schwinn build
- 9C 2807 rear hub motor
- Lyen 12fet 3077 controller
- 15s2p (10 AH) Turnigy lipo (because of the size/weight and I already have the charging setup for them)
- CycleAnalyst v2.3
- 2x Grintech torque arms
- Rear Tektro C326 caliper brake (on order)
- Hand made leather saddlebags


Being a step-through frame, I knew that I was going to have to put the batteries and controller in saddlebags. Thanks to Paul's leatherworking inspirational posts, I decided to give making my own bags a shot. So glad that I did, because I think they turned out pretty good for my first attempt!

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In this picture, you can see the on/off switch in the side of the left saddlebag so the bike can be turned on/off without opening the bags.
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At these power levels I could probably get away with just one torque arm, but I went with two to be safe. One oriented upwards, the other down, to account for both acceleration and regen braking forces.

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The bike rides great! The higher riding position and rear weight bias definitely make it less stable at speed than mine, but up to the 31 MPH top speed it seems fine.

From 0-25 MPH it actually out accelerates my Golden Motor 901 hub motor build, I assume due to the slower wound motor? Or it could be because I am carrying twice the amount of batteries on my bike...

When building the bags, I wanted to make the internal portion that the batteries and controller were mounted to easily removable for charging and replacing.

Here is a picture of the internal structure of the bags:
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Here you can see the channel I routed into the sides for the mounting board to slide in. This allows me to slide out the batteries by just unplugging one connection:
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And a picture of how I planned on populating each saddlebag. Batteries in one bag, controller/fuse/killswitch in the other. Since the controller would be enclosed, I am using four 40mm CPU fans to move the air to cool it. The bottom two for intake and the top two for exhaust, with holes cut into the saddlebags on the inside to allow the fans to access the open air.
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awesome motorized bicycle build. clean and something that will make you smile every time you see your wife ride it. awesome leather bags, I am really liking the plain uncarved look. I have been looking at alligator and a few other things to make my next bag with.

tell us about your battery packs when you have time, i really like the set up
 
Thanks Paul! The pack is made from six 5s 5AH Turnigy 20C lipo bricks. I wired three bricks in series to make "pack A" at 15s 5AH and the other three bricks in series to make "pack B", the attached those in parallel to make the whole pack 15S 10AH, 61V hot off the charger and 54V nominal.

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The bricks are mounted to the board by industrial strength velcro on the bottom, and the velcro strap on the top was just for extra security but likely not needed. But better more secure than needed!

I did not take a picture of the wiring harnesses that I made, but basically a bunch of 4mm HXT bullet connectors on the ends and connected the wires with copper crimp sleeves and covered those with heatshrink. One thing that I also did was label each battery connector and the corresponding harness connector to help avoid misplugs. A1 to A1, A2 to A2, etc...

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thank you so much, I would like to build my own batteries for my motorized bicycle someday however my knowledge of electrical is next to nil. going to look up parts and prices. I have 3 48v charges which I believe charge up to 58.4 volts so I would like to make my battery packs that could be used with my chargers. It would be nice to have some control of the shape of the battery packs so I could make to fit in the frame of my mountain bike and of course a nice leather bag to hold them in. thank you for the inspiration, I am really excited about doing something like this but had no idea where to start.
couple other questions, do you use a bms with a set up like this?
do you charge all the batteries at once or one at a time?
I think the controller on the magic pie will only handle 60v max so want to get the most juice I can of course
 
i agree dan, everything is so clean and you can see the time put into it by the battery construction, the bag and the wiring. its all very professionally done and makes one heck of a motorized bicycle.
 
Thanks fellas! It was fun to build and she gets a kick out of running errands on the bike. I added a rear Tektro C324 caliper. It is not nearly as scary to stop, now. I do want to replace the stock pads with Kool Stop salmon pads soon, though.
 
What kind of range do you expect with the current setup?

Cruising at 30 MPH (neighborhood speed limit is 25), with no pedaling and frequent stops, I would expect 10 - 15 miles. Since most of her trips are to Walgreens on the other side of the neighborhood (1.5 miles each way) or to her friends' houses nearby, I stuck with a pretty small battery pack.

If I were concerned about more range with the current setup I would dial back the amps on the controller, but right now I have it set for torque at 45 battery amps and 100 phase amps.

I also thought about adding another strap on pack to the top of the rear rack in case she wants to venture farther out. Make a matching rectangular battery box with the remaining leather. I might just do that anyway for the carrying capacity for small grocery items, six pack to bring home because she loves me, etc...
 
Thank you for the rapid reply. Just what I wished to hear as well. Just sussing things out for now but looking at going electric and dumping the whole china girl aspect.
 
Yup, after going electric I have not regretted the move from a China Girl. While the little 2 stroke looks cool on a bike, the charge-and-go nature of ebikes makes it less of a question on whether I will get back home under motor power or pedal power, LOL. Love the reliability.

That being said, I am sure that one day I will have another gas bike. But mainly because I just like building these things. Now that I have a welder, I am thinking a custom frame around a 4 speed Lifan.
 
me either, no smells, no maintenance. no gas leaks in the garage the list goes on, I will never go with a gas engine motorized bicycle again.
 
I sort of doubt I'll ever go back to gas powered motorized bicycles. Every day that goes by now, the gas bikes seem more and more limited, and my electric seems less and less.
 
Thanks for the replies folks. I am going to do a bit more research and clear up a few projects on the honey do list then dive in.
I am going to build another gas bike down the road but I think I will find a nice vintage motor and build the bike around it.
 
Hey Larry,

Everything I used is posted in this thread, is there anything in specific you are looking for?
 
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