Greetings everyone. I'd like to share with you my latest project. It's a Sikk fat tire beach cruiser with a Cyclone 3000w motor and custom built battery box.
I had a few goals for this project, which included:
1. Make something big guys could ride. This bike is designed for guys 5'9" and up and can handle up to a 250lb rider.
2. Use simple gearing without derailleurs, if possible.
3. Give a fat bike a try.
I upgraded some items on the bike to improve the ride and braking. I changed the tires to 120 tpi Vee Rubber V8s and upgraded the brakes to Avid DB1 hydraulics. The bike came with oversize ape-hanger handlebars which I found uncomfortable, so those were changed to 5-inch risers.
The cost of the bike including the upgrades was about $700.
The battery box is made from aluminum (0.063 in.) which came from a local metal shop. The plastic (0.125 in.) for the sides is standard stock from Grainger. I also purchased a small sheet metal bender to make the bends and a mini table saw to cut the plastic (both from Harbor Freight). The box is large enough for the battery and all the connectors. The wires enter through the bottom and on the front of the box is a panel mount XLR port for charging. The box is attached to the bike using U-clamps I made from some extra aluminum. The clamps were wrapped in heat shrink and foam strips added to the box sides to prevent frame scratching and give a nice, snug fit.
Materials for battery box was about $50.
The battery is a pair of 6s 16AH Multistars from Hobby King wired in series for 12s. I added a 60A lipo BMS from Greentime and built a custom harness for it. Connectors are XT-90 anti-spark for the discharge wires and XT-60 for the charge wires.
Battery cost was about $350.
Installing the Luna Cycle Cyclone 3000W was fairly straight forward, but did require a few mods. The bottom bracket is 120mm, so I had to get some longer bolts and extra spacers to make it fit. I was also concerned that the extra width of the BB would put too much stress on the bolts, so I cut out some tabs out of some scrap to secure the motor to the bolts on the non-drive side for extra support. I used a second hose clamp instead of the large zip-tie to secure the motor to the frame. The hose clamps were also wrapped in heat-shrink so they wouldn't scratch and better blend-in with the rest of the bike. I swapped the 44t inner chainring with a 36t to slow the bike down a bit. I used a pair of Origin-8 chain tensioners to keep proper tension on the chain.
Cost of motor kit and additional parts was about $450.
The ride is really a lot of fun. It a has a lot of grunt, which is what I was after. The cyclone is a bit loud but I'm getting used to it. Plus I've read the gearbox gets quieter as it wears in. The extra volume of the fat tires take a little getting used to on the street. I did limit the speed to 25 mph as I feel this is fast enough for the frame and stock rims. With the 3-speed I can easily climb any hill in my area. Acceleration is very quick.
Other accessories to complete the build: Luna Cycle e-brake sensors, Luna Cycle rear LED light, Ebay 10W headlight, cost about $50.
Total cost of the build was about $1600.
More pictures of this and my other projects can be seen on my website: www.ebikekc.com
Thanks for looking!
Dave
I had a few goals for this project, which included:
1. Make something big guys could ride. This bike is designed for guys 5'9" and up and can handle up to a 250lb rider.
2. Use simple gearing without derailleurs, if possible.
3. Give a fat bike a try.
I upgraded some items on the bike to improve the ride and braking. I changed the tires to 120 tpi Vee Rubber V8s and upgraded the brakes to Avid DB1 hydraulics. The bike came with oversize ape-hanger handlebars which I found uncomfortable, so those were changed to 5-inch risers.
The cost of the bike including the upgrades was about $700.
The battery box is made from aluminum (0.063 in.) which came from a local metal shop. The plastic (0.125 in.) for the sides is standard stock from Grainger. I also purchased a small sheet metal bender to make the bends and a mini table saw to cut the plastic (both from Harbor Freight). The box is large enough for the battery and all the connectors. The wires enter through the bottom and on the front of the box is a panel mount XLR port for charging. The box is attached to the bike using U-clamps I made from some extra aluminum. The clamps were wrapped in heat shrink and foam strips added to the box sides to prevent frame scratching and give a nice, snug fit.
Materials for battery box was about $50.
The battery is a pair of 6s 16AH Multistars from Hobby King wired in series for 12s. I added a 60A lipo BMS from Greentime and built a custom harness for it. Connectors are XT-90 anti-spark for the discharge wires and XT-60 for the charge wires.
Battery cost was about $350.
Installing the Luna Cycle Cyclone 3000W was fairly straight forward, but did require a few mods. The bottom bracket is 120mm, so I had to get some longer bolts and extra spacers to make it fit. I was also concerned that the extra width of the BB would put too much stress on the bolts, so I cut out some tabs out of some scrap to secure the motor to the bolts on the non-drive side for extra support. I used a second hose clamp instead of the large zip-tie to secure the motor to the frame. The hose clamps were also wrapped in heat-shrink so they wouldn't scratch and better blend-in with the rest of the bike. I swapped the 44t inner chainring with a 36t to slow the bike down a bit. I used a pair of Origin-8 chain tensioners to keep proper tension on the chain.
Cost of motor kit and additional parts was about $450.
The ride is really a lot of fun. It a has a lot of grunt, which is what I was after. The cyclone is a bit loud but I'm getting used to it. Plus I've read the gearbox gets quieter as it wears in. The extra volume of the fat tires take a little getting used to on the street. I did limit the speed to 25 mph as I feel this is fast enough for the frame and stock rims. With the 3-speed I can easily climb any hill in my area. Acceleration is very quick.
Other accessories to complete the build: Luna Cycle e-brake sensors, Luna Cycle rear LED light, Ebay 10W headlight, cost about $50.
Total cost of the build was about $1600.
More pictures of this and my other projects can be seen on my website: www.ebikekc.com
Thanks for looking!
Dave
Comment