![\"Power](\"https:\/\/www.power-e-bike.fr\/blog\/wp-content\/uploads\/2015\/05\/MOTEUR211.jpg\" "\\"\\"")
<\/a> with a very attractive combination of quality, performance and price. I still had to choose the version.\nI wanted an electric bike both for my hilly 14km commute and for riding forest trails. I therefore needed a useful range and a respectable top speed.
\nI chose the RH205S 280\/380<\/p>\n
paired with a homemade battery of 20 LiFe cells, 10 Ah (60v), which I designed and assembled myself. Vario Kaktus mountain bike: DH\/FreeRide, long-travel Marzocchi fork, hydraulic brakes with 203mm discs. Preparing the frame: adding aluminium battery mounts and repainting. Installing the motor with homemade torque arms, necessary at this power level. The motor fits perfectly without spacing washers, and the brake disc naturally falls into place. Fitting the motor controller inside the frame.<\/p>\n Assembling and soldering the battery cells.<\/p>\n The battery has an unusual shape so that it fits into the available space around the frame. It has a charging\/balancing connector and a power connector and sits in a removable aluminium case, allowing it to be taken out for charging and storage.<\/p>\n The panel supports.<\/p>\n Shaping the carbon cloth over a polystyrene mould and laminating it with epoxy resin.<\/p>\n The bike, ready to ride\u2026<\/p>\n<\/a>with a 28-amp Power E-bike controller<\/p>\n<\/a><\/p>\n
\nI also ordered a freewheel with an 11-tooth sprocket from Power E-bike so that I could pedal along with the motor at planned speeds above 40km\/h.<\/p>\n
\nI also intend to build and program an onboard computer using an Arduino microcontroller and a display to manage consumption and range, along with information such as speed and temperature. I will not describe that project in this article.
\nThe order was placed with Power E-bike and delivered very quickly. I would also like to highlight the company\u2019s professionalism.
\nThe mountain-bike conversion could begin.<\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a>
\nMaking a left-thumb throttle trigger with an electric brake lever operated by a finger.<\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a>
\nOf course, these components could not remain exposed around the frame, so I had to make side panels. I chose carbon fibre for its appearance and fitted aluminium supports to the frame to secure them.<\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/a>
\nTesting could begin.
\nFrom the first few metres, the choice of motor proved sound.
\nThe bike accelerates strongly, pedalling is almost unnecessary and it quickly reaches its top speed of 50 km\/h. Even with the 11-tooth sprocket, I cannot keep up with the motor by pedalling at that speed: I can contribute up to 40 km\/h with the 11-tooth sprocket and a 42-tooth chainring. Given the acceleration, changing gears is also unnecessary: largest chainring and smallest sprocket all the time.
\nClimbs are straightforward too; only very steep slopes really challenge the motor.
\nFor range, I get about 30km with sporty riding and about 50km at 60 % power, keeping the average speed around 25, 30 km\/h. That completely meets my needs.
\nI should also mention that I use road-oriented Kenda Kiniption tyres in 26×2.3, rather than off-road tyres.<\/p>\n