liveforphysics
100 TW
Great job on a nice build!
Spare parts E-BMX Build "Deathbike Junior"
- Thread starter www.recumbents.com
- Start date
www.recumbents.com
10 kW
For sure he will be helping to fix whatever gets broken. :lol:
Error in judgement #3536. Spray painting when the remnants of hurricane Alberto are passing your house.
I neglected to paint the fork last night and it was way too humid to be painting tonight but I did it anyway and now it's all cloudy instead of shiny. Hopefully there's enough paint left in the can to make it pretty. Otherwise it's going together fine. It's amazing how much easier a bike goes together after all the parts have been pre-fit!
Error in judgement #3536. Spray painting when the remnants of hurricane Alberto are passing your house.
I neglected to paint the fork last night and it was way too humid to be painting tonight but I did it anyway and now it's all cloudy instead of shiny. Hopefully there's enough paint left in the can to make it pretty. Otherwise it's going together fine. It's amazing how much easier a bike goes together after all the parts have been pre-fit!
www.recumbents.com
10 kW
It's done!
Finished re-assembling it and adjusting the chains.
Hmm, maybe I should paint over the pink flowers on the chainring? :lol:
Finished re-assembling it and adjusting the chains.
Hmm, maybe I should paint over the pink flowers on the chainring? :lol:
wturber
1 MW
www.recumbents.com said:
That was totally what I was thinking!! I'm a fan of hammered finish Rustoleum for rattle can finishes that are durable and look decent.
www.recumbents.com
10 kW
I used a can of car paint on the frame. It seems to be better than the rustoleum style paint. Painted the chainring black! No nobody will ever know that it was a pink bike for a little girl!
liveforphysics
100 TW
Looks great! Nice build!
wturber
1 MW
www.recumbents.com said:
Sure. Car paint should be pretty tough - and you can't go wrong with black IMO. :^)
www.recumbents.com
10 kW
Sounds like he has been riding it every day this week and charging it every night. So far so good...
www.recumbents.com
10 kW
I added a bike computer to see how many miles he put on it. I also added an "always on" bright tail light so he knows to turn off the battery. The LEDs on the throttle are rather dim so it got left on occasionally. After he complained that it didn't get very far before cutting off, I had to explain that it really needed to be charged overnight to allow the battery to balance. It's been fine since. The headset was loose and the chains were very loose so I adjusted those. Looks like it goes about 16MPH, which is slower than I thought, but keeps it pretty bulletproof. He hasn't asked for more speed yet and I could get a cog with an extra tooth or two easily but he doesn't wear a helmet so I'm a bit apprehensive about that. Kickstand is not working great, spring may have gotten hot and lost its temper. I will need to fix that.
It's amazing how you can cobble parts together and everything works!
Warren
It's amazing how you can cobble parts together and everything works!
Warren
Looks like fun (at least for the rider). 16mph top speed is about right for one of those motors. If you change the gearing, it might not go much faster unless going downhill. Eventually it will just need a (much) bigger motor. 
www.recumbents.com
10 kW
I used this same motor on my recumbent commuter for a couple years with a fairing and geared it to 30MPH. It got there pretty slowly but it worked ok until I finally succumbed to the need for speed and installed the recumpence RC motor drive. I agree that it's not strong enough to go much faster.
Yep, in a year or so if he's still riding it, it may be time for an upgrade.
Warren
Yep, in a year or so if he's still riding it, it may be time for an upgrade.
Warren
www.recumbents.com
10 kW
Apparently the kid has been trying to fix the kickstand before I could get to it. With a hammer. 
wturber
1 MW
www.recumbents.com said:Apparently the kid has been trying to fix the kickstand before I could get to it. With a hammer.
Well, I can imagine some problems that a hammer could help fix. I'm assuming that wasn't the right approach for this problem though.
www.recumbents.com
10 kW
No, the correct tool was an economy sized tractor wrench (crescent wrench), or course! I just bent the flange that the kickstand flange runs in out a bit and that fixed it.
wturber
1 MW
www.recumbents.com said:
I'd chuckle, but I'm the guy who just destroyed his bench vise last weekend. I was using it to flatten 1/2" aluminum tube ends in order to create attachment points for struts to reinforce my rear rack. No room for smugness here. :^)
www.recumbents.com
10 kW
Later last summer I added a headlight and another switch so he could turn the lights on and off independently of the main motor power. He said "so basically this is a motorcycle?". Yes. Yes it is.
He rode the e-bike all last summer and it was still going strong this year until recently when his friend failed to shut off the power switch and left the lights running after using it. I saw it sitting there with dim lights one or more days later. I put it back on the charger for a couple days but now it just gets about a block down the road before the BMS kills the power. I removed the battery module from the bike and I will start the diagnostics. So far I have measured the battery voltages and they are all about 3.3-3.5 volt which is correct for an lifepo4 battery.
Next I will need to attach a load to see if one or more cells is saggy. Would a 200watt quartz halogen light be appropriate for this 24V Ping pack?
If one of the cells is bad, I'll just switch the pack out for the other 24V pack that was part of the 48V split pack Ping battery that I bought over 10 years ago and then abused for many years.
I had a conversation with the now 14 year old, and he said he'd like it to be quieter and go faster. I was thinking about building him something new until I saw him throw a bike into another bike. No wonder I have to fix those bikes almost weekly.
Warren
He rode the e-bike all last summer and it was still going strong this year until recently when his friend failed to shut off the power switch and left the lights running after using it. I saw it sitting there with dim lights one or more days later. I put it back on the charger for a couple days but now it just gets about a block down the road before the BMS kills the power. I removed the battery module from the bike and I will start the diagnostics. So far I have measured the battery voltages and they are all about 3.3-3.5 volt which is correct for an lifepo4 battery.
Next I will need to attach a load to see if one or more cells is saggy. Would a 200watt quartz halogen light be appropriate for this 24V Ping pack?
If one of the cells is bad, I'll just switch the pack out for the other 24V pack that was part of the 48V split pack Ping battery that I bought over 10 years ago and then abused for many years.
I had a conversation with the now 14 year old, and he said he'd like it to be quieter and go faster. I was thinking about building him something new until I saw him throw a bike into another bike. No wonder I have to fix those bikes almost weekly.
Warren
www.recumbents.com
10 kW
I did a bit more testing. I used the 200 watt QH light to load it a bit (light is dim) and checked cell battery voltages and none of them are sagging.
I'll let it discharge a while and check it again and recharge it again but I think I'm just going to take the BMS out of the discharge circuit and just use the BMS for charging for a while. Yes he may discharge it way low and damage the battery more. I'll see how it goes.
I'll let it discharge a while and check it again and recharge it again but I think I'm just going to take the BMS out of the discharge circuit and just use the BMS for charging for a while. Yes he may discharge it way low and damage the battery more. I'll see how it goes.
www.recumbents.com
10 kW
armandd said:May I know where did you get the counter clockwise freewheel for the Currie/Unite motor? I only have the clockwise version (freewheels in CCW direction).
20180110_173805ed.jpg
The Curry motor/gearbox doesn't have a freewheel, the freewheel is at the hub. The hub I'm using came with the Mongoose trail e-bike. It has a freewheel on both sides of the hub. I'd like to know where to find more of those too.
www.recumbents.com
10 kW
Deathbike Junior lives, after bypassing the BMS on the discharge side. The 'ole Ping battery tested ok but maybe it's just sagging too far and that's kicking the LVC on the BMS. In any case, it still maxes out at about 17 MPH and he can ride faster than on his MTB now, so he's asking for more speed again. I'm always up for another project!
I don't think he's ready for a 30MPH bike yet, but maybe we can squeeze a bit more performance from this bike. I have seen people running the Currie geared DC motors at 36V and I'm thinking this is the fastest/cheapest way to get more speed out of this bike. I have another controller floating around and need to check if it can be run at 36V.
I'm not using this battery holder any more, two of the 3 rows below would be 36V. I could package them back to back which would be fairly compact and they should fit in the same battery box.
I need to source 18650 batteries, a 36V LiPo BMS and charger. I have been using the Sammy 25Rs but those are still pricey.
Suggestions for inexpensive yet quality 18650s for this project?
Warren
I don't think he's ready for a 30MPH bike yet, but maybe we can squeeze a bit more performance from this bike. I have seen people running the Currie geared DC motors at 36V and I'm thinking this is the fastest/cheapest way to get more speed out of this bike. I have another controller floating around and need to check if it can be run at 36V.
I'm not using this battery holder any more, two of the 3 rows below would be 36V. I could package them back to back which would be fairly compact and they should fit in the same battery box.
I need to source 18650 batteries, a 36V LiPo BMS and charger. I have been using the Sammy 25Rs but those are still pricey.
Suggestions for inexpensive yet quality 18650s for this project?
Warren
www.recumbents.com
10 kW
Thanks, I have asked for a quote on those from battery-bros.
www.recumbents.com
10 kW
Aftermath of his crashy friend crashing into him. Side mounting bolt fell out probably before crash. Bottom bracket is bent so the motor is in contact with the tire.
Removed the motor, reformed bracket with medium size pursuader tool, reinstalled motor, added new side bolt and a blob of JB Weld to increase chances of having it stay in place. And..... He's back on the road.
Removed the motor, reformed bracket with medium size pursuader tool, reinstalled motor, added new side bolt and a blob of JB Weld to increase chances of having it stay in place. And..... He's back on the road.
www.recumbents.com
10 kW
According to the speedo on the bike he's got close to 300 miles on the bike so far. Top speed is now down to about 13 MPH, so the ol' Ping is slowly losing juice.
The latest failure is that the left pedal completely stripped out the threads and fell off. I have never seen anything like that before! I think the pedal must have been made of cheese. I took a pedal off of another junk bike and was able to get it screwed about 3/4 of the way into the munged threads. That didn't last long and now there is just a metal rod sticking out of the crank arm. Time to find some new less cheesy pedals!
Warren
The latest failure is that the left pedal completely stripped out the threads and fell off. I have never seen anything like that before! I think the pedal must have been made of cheese. I took a pedal off of another junk bike and was able to get it screwed about 3/4 of the way into the munged threads. That didn't last long and now there is just a metal rod sticking out of the crank arm. Time to find some new less cheesy pedals!
Warren
