I completed my BSSHD-equipped mt bike build this weekend, at least enough to take it for a test ride and test general function.
The build was onto a Motobecane HT529, a 29er-wheel from Bikesdirect.com. I didn't bench test the motor, so it was a breath-holder when I ventured out onto my driveway the first time. I was sent the wrong throttle (left instead of right), didn't want to try to figure out the hydraulic brake sensors, and the gear sensor cable is too short to reach from any mounting points to the controller jack, so I didn't connect use any of those features. Regardless, the system running on PAS was really cool - I had never ridden an e-bike before, so I didn't know what to expect. I AM SUPERMAN!!!
I ran the bike primarily in stock programming level 1 and 2 (out of 5), and was amazed at how smooth the power transition. I generally couldn't feel or hear the motor at all, I was just able to ride up a typical 2nd gear @ 3MPH hill at 20MPH. Totally wicked. I rode it a couple of miles down to my fish n' game club, where everybody wanted to ride it. Now they all want one. Total bike weight including battery is roughly 50 pounds (23kg).
The build wasn't technically hard, but was delayed due to a couple of omissions and errors with the original package. Luna has been good about correcting those errors, though each delay the project a week due to mailing time.
1) The "standard" motor drive supplied (stickered 73mm) is only compatible with a 73mm bottom bracket - spacers are required for a 68mm bracket but weren't included originally. 5mm on the non-drive side centers cranks vs. frame, but chain ring didn't have enough clearance to chain stay in that position. I instead used 2.5mm spacers on either side of the BB, creating a 5mm crank arm to frame offset toward the drive side. I didn't notice the offset wile riding. The chain line was just about perfect with the Luna Eclipse chain ring in this position. I face a potential problem in rotation of the motor due to the mounting plate teeth being driven into a spacer instead of the BB. I have not seen evidence of rotation so far, however. I used a blob of epoxy putty between the down tube and motor to help disburse motor-torque created pressure on that point.
2) Tragically, the frame triangle on my bike is too small to fit any of the Luna-provided batteries. I ended up getting a Slim Line and mounting it on a rear rack, which is about the worst place you can put a battery. It is my least-favorite part of the design, was the hardest part of the build (5 hours), and was the sole problem that surfaced on my initial outing. It is fairly stealthy though. I made a mounting plate out of epoxy-laminated graphite carbon fiber, which worked great, but ended up vibrating audibly against the rack. It needs a couple more mounting bolts through the battery rack and possibly a thin layer of isolation material.
3) Wiring was somewhat trivial - the main harness and speed sensor required about a dozen zip-ties and I didn't connect the brake sensors, throttle, or gear sensor lines. I connected the Slim Line pack to the motor harness using an XT90-S anti-spark plug. As the Slim Line battery has a sliding mount into a connector, many hard-connect the pack to the controller and (I guess) live with the spark when they push the pack into the mount. I probably won't remove my battery much, but when I do, I disconnect the anti-spark plug first and re-plug it after re-inserting the battery. No sparks yet.
The only problem I discovered after the shakedown cruise was vibration from the battery mounting plate that came about after a couple of miles. The mounting plate I made extends off of a ~10" rack toward the front - the back of the battery pack is roughly flush with the back of the rack, the front of the pack and mounting plate extends about 6-7" off of the rack. I epoxied the CF plate onto the aluminum rack before bolting it down, but the epoxy separated toward the front of the rack. There are only 4 mounting bolts on the rack (the other 4 hold the battery mount and mating socket to the plate), and one was damaged when I discovered a mounting depth design flaw in the battery mount. For those who get a Slim Line - the supplied bolts don't sit low enough into the plastic mount to clear the battery. They require a small amount of additional counter-sinking to get the heads flush with the plastic surface, and the battery will not slide into place with the heads higher than flush.
One thing I noticed - the display seemed to change color at one point - I must have hit a button by accident or something. It went from a white background to something darker and I couldn't see it at all. At night, the white display is too bright and blinds you. Is there a night mode on the display that I engaged by accident?
The build was onto a Motobecane HT529, a 29er-wheel from Bikesdirect.com. I didn't bench test the motor, so it was a breath-holder when I ventured out onto my driveway the first time. I was sent the wrong throttle (left instead of right), didn't want to try to figure out the hydraulic brake sensors, and the gear sensor cable is too short to reach from any mounting points to the controller jack, so I didn't connect use any of those features. Regardless, the system running on PAS was really cool - I had never ridden an e-bike before, so I didn't know what to expect. I AM SUPERMAN!!!
I ran the bike primarily in stock programming level 1 and 2 (out of 5), and was amazed at how smooth the power transition. I generally couldn't feel or hear the motor at all, I was just able to ride up a typical 2nd gear @ 3MPH hill at 20MPH. Totally wicked. I rode it a couple of miles down to my fish n' game club, where everybody wanted to ride it. Now they all want one. Total bike weight including battery is roughly 50 pounds (23kg).
The build wasn't technically hard, but was delayed due to a couple of omissions and errors with the original package. Luna has been good about correcting those errors, though each delay the project a week due to mailing time.
1) The "standard" motor drive supplied (stickered 73mm) is only compatible with a 73mm bottom bracket - spacers are required for a 68mm bracket but weren't included originally. 5mm on the non-drive side centers cranks vs. frame, but chain ring didn't have enough clearance to chain stay in that position. I instead used 2.5mm spacers on either side of the BB, creating a 5mm crank arm to frame offset toward the drive side. I didn't notice the offset wile riding. The chain line was just about perfect with the Luna Eclipse chain ring in this position. I face a potential problem in rotation of the motor due to the mounting plate teeth being driven into a spacer instead of the BB. I have not seen evidence of rotation so far, however. I used a blob of epoxy putty between the down tube and motor to help disburse motor-torque created pressure on that point.
2) Tragically, the frame triangle on my bike is too small to fit any of the Luna-provided batteries. I ended up getting a Slim Line and mounting it on a rear rack, which is about the worst place you can put a battery. It is my least-favorite part of the design, was the hardest part of the build (5 hours), and was the sole problem that surfaced on my initial outing. It is fairly stealthy though. I made a mounting plate out of epoxy-laminated graphite carbon fiber, which worked great, but ended up vibrating audibly against the rack. It needs a couple more mounting bolts through the battery rack and possibly a thin layer of isolation material.
3) Wiring was somewhat trivial - the main harness and speed sensor required about a dozen zip-ties and I didn't connect the brake sensors, throttle, or gear sensor lines. I connected the Slim Line pack to the motor harness using an XT90-S anti-spark plug. As the Slim Line battery has a sliding mount into a connector, many hard-connect the pack to the controller and (I guess) live with the spark when they push the pack into the mount. I probably won't remove my battery much, but when I do, I disconnect the anti-spark plug first and re-plug it after re-inserting the battery. No sparks yet.
The only problem I discovered after the shakedown cruise was vibration from the battery mounting plate that came about after a couple of miles. The mounting plate I made extends off of a ~10" rack toward the front - the back of the battery pack is roughly flush with the back of the rack, the front of the pack and mounting plate extends about 6-7" off of the rack. I epoxied the CF plate onto the aluminum rack before bolting it down, but the epoxy separated toward the front of the rack. There are only 4 mounting bolts on the rack (the other 4 hold the battery mount and mating socket to the plate), and one was damaged when I discovered a mounting depth design flaw in the battery mount. For those who get a Slim Line - the supplied bolts don't sit low enough into the plastic mount to clear the battery. They require a small amount of additional counter-sinking to get the heads flush with the plastic surface, and the battery will not slide into place with the heads higher than flush.
One thing I noticed - the display seemed to change color at one point - I must have hit a button by accident or something. It went from a white background to something darker and I couldn't see it at all. At night, the white display is too bright and blinds you. Is there a night mode on the display that I engaged by accident?
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