My 48v 500W Cruiser Chopper Project

[chopper_elec]

Boy that's a decent amount of sla love. I was originally going for nimh from rc cars but the temptation of lifepo4 was just too much. Has anyone ever had any safety issues with them like we do with lipo batteries? Lifepo4 seem so much more forgiving.
from

[amberwolf]

You can have "safety issues" with any battery chemistry, and I've seen or heard of at least one example of every one of them failing in a dramatic fashion.


I don't use my SLA much anymore, except for experiments and to power stationary things (like a server-sized UPS whenever there are power outages).

Once I got NiMH (thanks to Ianmcnally), I used it in preference to the heavy SLA. I saved and scrimped and shorted myself on things and bought some Thundersky LiFePO4 cells, but didnt' quite have enough voltage to do what I needed with them, and was afraid to use them without a BMS after various problems I'd read on DIY Electric Car forums and elsewhere (like here), and was taking forever to build a BMS for them out of parts from a few people here on ES....

Later I got a damaged "prebuilt" LiFePO4 (thanks to Bluestreak), and after repairing it I used that in preference to the NiMH, because it was a little more power-dense, though not really any lighter than the NiMH, it had more usable power.

Later I started experimental LiPo-type packs, including good and repaired RC-LiPo from Mdd0127 and others including Ohzee, using this over the others because it is a lot more power-dense *and* it can supply a much higher current level than the others without as much voltage sag (although the SLA can supply jsut about any current levle I care to draw from it, it won't last very long at those rates and it sags so much that the higher current doesn't really result in that high of a total power level).

I havent' tried NiCd yet, htough I have a pile of old powertool packs to disassemble and rebuild, if I ever get the time to try it.

Same thing for laptop LiCo cells...got a lot of them but haven't gotten a pack built yet, despite starting several times.

Haven't tried A123 either, only have one cell of the larger cylindrical type, don't know it's condition.

So far I've found they all have their place, and their uses, but basically I prefer whatever has the best power and energy density, as it makes for the lightest smallest usable pack on my already pretty heavy bikes.


BTW: at one point I considered piling all of my batteries on a trailer to get me to Tucson for the Death Race, but it would be an all-day (12-18 hour) trip to get there at the state limit of 20MPH plus probable stops to fix things and rest and whatnot. Then I guesstimated the energy usage because of hills and slopes vs the weight of that trailer of batteries, and I would just about make it there then have to spend a week charging it all to get back. That's assuming I didn't get run over by someone going 90MPH on the highway I'd have to be riding on....

[chopper_elec]

Wow you've had some awesome experience in the past with batteries indeed.

I ended up test fitting the front hub motor and on each wheel there is 2 washers on the inside of the forks and 1 on the outside (then the nut on each end) but I was not able to fit

One of these washers (the second one from the hub motor) has a little lip on the end of it which im guessing helps to stop the hub from spinning in the dropouts

My only issue is, if I run 1 washer inside each fork there is too much space from the fork to the hub, and if i use 2 washers inside each fork on the axle there is not enough room to slide in the forks.

Has anyone else had this particular issue? Its like I need 1.5 washers haha

EDIT: By the way that avatar pic of mine is actually my new Riding Goggles and helmet lmao

[amberwolf]

IIRC, http://ebikes.ca carries spacer washers in various thicknesses.

Your local hardware store probably also has washers that will fit.

Alternately you can hold a washer with vice grips and use an angle grinder or bench grinder to shave it down.

[chopper_elec]

IIRC, http://ebikes.ca carries spacer washers in various thicknesses.

Your local hardware store probably also has washers that will fit.

Alternately you can hold a washer with vice grips and use an angle grinder or bench grinder to shave it down.

Thanks for the heads up. I was worried if they weren't elongated, but then again I am using a torque arm too.

[amberwolf]

Spacer washers are just washers; doesn't matter what shape the axle hole is. Only the tabbed washers would make any difference not having the axle-shaped hole.

[chopper_elec]

Spacer washers are just washers; doesn't matter what shape the axle hole is. Only the tabbed washers would make any difference not having the axle-shaped hole.

Thanks for that mate. I am very excited to get it all on there. Would I be correct in saying that I was looking for 12mm washers? I can't wait to get my battery which should be here next week. I am sure i'll get a lot of attention riding around with a dragster style bike (maybe not as much as a recumbent bike hahaha).

Now how to draw more attention.. lol

[amberwolf]

Just bring one of your exsiting washers, and match it's largest axle hole dimension to the new washer's hole size.

[chopper_elec]

Thanks mate

I am just working out which battery pack to get at the moment

I was wondering if the extra weight of a 48v 20ah battery would be worth it over a 48v 10ah one.

Here is one i've been considering:
http://www.aliexpress.com/product-fm/54 ... alers.html

Any opinions out of my choices
http://www.ebay.com.au/itm/48v-20ah-LiF ... 322wt_1037

I do seem to prefer a "packaged" battery pack in a hard case like in the first link, it makes it easier to carry and charge.

[chopper_elec]

I went on a good feeling and ended up picking up this lifepo4 48v 16ah pack

The guy that was selling it was really nice and honest and I was happy to give them a go.

[chopper_elec]

Is there any estimates on running time that I could expect out of my new 48v 16ah Lifepo4 battery?

I will be using a 48v 500w Conhis front hub motor on a 24" wheel.

I'm running through a few previous topics to ensure that the introduction process is correct, since the battery is new.

[chopper_elec]

Finally I have some decent Photos of my bike

 

Here is the beast in all her glory.



My most epic 48v 500w Motor Controller. They were kind enough to write 48v just in case I forgot what my order was haha.



My workbench (finally I cleared it enough to put all my goodies on it.



I got around to installing my super cheap eBay Bicycle Computer, visible on the right is my very epic eBay special Wildfire G13 phone holder (I mean't to get one for a G8 but luckily it fits relatively well enough)

This was a very proud day indeed, finally getting the original cheapie handlebar grips off and putting my electronic throttle in place. I'm still not sure if I like the positioning (as my arm is sort of twisted sideways in the first place).

I may end up using my thumb throttle in the long run. Is it strange to have to release your hand off the throttle to press the brake or could I have set it up badly?




Here is my el Cheapo eBay Speedo Sensor in place. It seems to do a decent enough job for now till I can afford a Cycle Analyst.



Here I am positioning the Narva Compac 100 fog light that will be used for longer rides, if I end up getting caught in the dark its nice to know I have some decent lighting to back me up.



Here is the same hand and fog light but this time I positioned it a bit higher up.



The cables and bracket definitely need some work, I bought them second hand a few years ago.





My Torque Arm Kit (I bought 2 just in case i'd need them). I'm still working out the best way to mount this.

[chopper_elec]

I'm off to the hardware store to pickup some washers for the axle and some washers to space out the long piece of the torque arm kit so it will sit flush against the dropouts.

The Battery should arrive if i'm lucky today, i'll give it a charge and check the voltages. I'm really hoping its a pouch cell pack due to the weight being around 6-7kg. Could there be a chance it could still be another type of lifepo4 pack even with such a light weight?

Its a 48v 16ah Lifepo4 pack. I'm sure the charger will be the first thing to go on me, i'm just hoping it won't destroy the battery as a result. Fixing it shouldn't be too much of an issue.

I will start running the wires for the headlight and fog light but I can only do this if the H3 globe arrives. Although weight is going to be 500-600g heavier I will be running an auxillary 6ah battery just for the accessories. I do have a 48v to 12v convertor on the way but i'd prefer knowing that each battery has its purpose.

[schmidty_81]

That looks Awesome.

Hey if you're still looking for a trailer I spied this one a while ago, I too have thought about this but like you say the kiddy ones are a bit wide. This one is for pets and is a fair bit narrower, could be just what you're after, might need just a few modifications though.

I live in the south east suburbs of Melbourne and have bought stuff off these guys in the past, they usually show up about 4 days after you buy it and their stuff's usually pretty good and reasonably priced.

http://www.oo.com.au/Bicycle-Bike-Trail ... mmendation

[chopper_elec]

That looks Awesome.

Hey if you're still looking for a trailer I spied this one a while ago, I too have thought about this but like you say the kiddy ones are a bit wide. This one is for pets and is a fair bit narrower, could be just what you're after, might need just a few modifications though.

I live in the south east suburbs of Melbourne and have bought stuff off these guys in the past, they usually show up about 4 days after you buy it and their stuff's usually pretty good and reasonably priced.

http://www.oo.com.au/Bicycle-Bike-Trail ... mmendation

Hey Mate
Thanks for that information. I'll be sure to check it out. By the time I was to build a trailer myself and buy the supplies required it would easily exceed the costs of buying one complete and professionally designed haha.

[chopper_elec]

My battery and charger arrived today, I am truly amazed at the size of the battery haha. Its light but it looks like it should weigh more.

I reckon it weighs a bit more than 1 of my sla 12v 12ah batteries.

I still need to solder the connector on the end of the battery to a connector.

I will end up using the IEC connector for convenience as the controller has the same connector on the end.

I just need to make sure I don't mix them up as the charger also uses one of those IEC connectors.

Next will be de-pinning the hub motor connector so I can get the right washers in place so I can finally mount the hub onto the bike.

I did buy one of these which will be used to control the horn, headlight and indicators lol

[chopper_elec]

I did the magnet test tonight and found out that the front forks and dropouts are actually steel which is great news I guess lol. They are quite thick too, I would say they are fairly thick as well so I won't feel so worried about the wheel falling off with my 48v 500w motor. I will still use a torque arm or even 2 (one on each side).

The only worry I have now is the actual welds on the dropouts to the forks themselves ha ha

[Scruffoid]

Just thought id give you an answer to your range question.

Your battery is 48V and 16Ah

So your watt hours is 48 * 16 = 768Wh

So if you were to ride your bike consuming 500Watts constantly it would last for 1.5hours of riding. Of course Range is based upon speed so your gonna have to see how fast you are travelling to work that out arent you. Letting off the throttle a little extends your range by a lot.

Also you won't be consuming a full 500W all the time as you ride so it comes down to the terain you are riding over as well. But i would think you are gonna go about 40-45K's on a charge and if you pedal then your just gonna go further arent you.

Make sure your tyres are pumped up and you'll go closer to your maximum range as well.

Good to see you almost there matey!

Love the frame your using although i wouldn't want to commute on it myself due to the amount of people that would be looking at it LOL. But i am really thinking of trying to find one of these for weekend fun!

[chopper_elec]

Just thought id give you an answer to your range question.

Your battery is 48V and 16Ah

So your watt hours is 48 * 16 = 768Wh

So if you were to ride your bike consuming 500Watts constantly it would last for 1.5hours of riding. Of course Range is based upon speed so your gonna have to see how fast you are travelling to work that out arent you. Letting off the throttle a little extends your range by a lot.

Also you won't be consuming a full 500W all the time as you ride so it comes down to the terain you are riding over as well. But i would think you are gonna go about 40-45K's on a charge and if you pedal then your just gonna go further arent you.

Make sure your tyres are pumped up and you'll go closer to your maximum range as well.

Good to see you almost there matey!

Love the frame your using although i wouldn't want to commute on it myself due to the amount of people that would be looking at it LOL. But i am really thinking of trying to find one of these for weekend fun!

Thanks

Oh 40-50km would be unreal, considering that is all done with a majority of motor power assisting.

I love the frame too, it feels sooo comfy and i've gone for 20-30km rides up all sorts of terrains and weather and its an awesome bike. The hub motor will only assist on those times that I may be struggling a bit but still want to enjoy the ride. I would be very tempted to still use it as a commuter vehicle but the looks that i'd get from work would either tell them i'm environmental and doing the right thing but at the same time they wouldn't wanna mess with me hahaha (especially with those goggles i'm wearing).

I'm off to the hardware store hopefully tomorrow for some P clamps, cable ties, some nuts and bolts and some washers. I'm hoping they are available in different sizes. Its likely i'd have to go to a dedicated bolt place to source out the right thickness which is still unknown as yet but I do know its roughly 1/2 the thickness of the shims on the bike atm.

Whats the first feeling like pushing off and knowing your not pedaling? I think that would be the wierdest feeling. I used to have one of those big moped style electric bicycles and it was so unbelievably heavy, the gearing on the pedals were so terrible so you could only go about 3-4km an hour with them lol

I am still trying to work out the wiring on the battery at the moment. It came with 2 crimped tab connectors, one of the wires is brown while the other is black. In my experience I always thought brown or black was negative doh.

I'm still trying to work out the cell type, is there any particular weight test I can do to ensure it isn't prismatic cells? I'm in the works getting a battery box done. I wouldn't mind putting it on the back of the bike but due to the design of my bike, the battery tray rack does not mount up to any points on the back of the wheel/seat. I am thinking of getting a front basket for the bike and store the battery there LMAO

[chopper_elec]

I made a bit of progress today and mounted up the Hub Motor to the wheel.

As recommended by members on here I was sure to take a photo of the hall sensor wires so once they are depinned I would know where to put them again.



 

 

Here is my mounting of the hub motor with washers. In Order from the Hub itself all the way to the end of the nut I used:

Washer – Washer – Tab Washer – Drop Out – Washer – Washer Torque Arm – Washer – Nut

I am wondering if I used too many washers haha They were required to space out the hub correctly. The dropout has barely any compression as the washers shimmed the inside much better than the factory washers included in the pack (too wide).




 

Here was my idea for the dropout reinforcement (one on each side)

The washers were used after the drop outs to space out the second piece of the torque plate in my hand. I was thinking of using that hole in the drop out for mounting the piece of torque arm. I would use big washers but with a small inlet diameter. Would you see any issues relating to this?


 

Here is another example of the idea I was thinking of:


 

I taped up the hub so it wouldn’t get scratched while mounting it in the dropouts. Slowly coming together.


 

Goodbye protection tape



 

 

The next thing as to find a good place to mount the controller. I was able to squeeze it in nicely behind the seat. I will be using P Clamps to mount it to the seat shaft. As a result the wiring should be really neat.
The top plate of the controller looks rusty but its actually the reflection of the wall opposite (covered with wood lol)

 

Here is another photo (with cloth to protect it from getting scratched up.



Here it is in all its glory. Delicious. Can’t wait to fire it up.


 

As a joke I bought one of those police alarms haha. I jokingly mounted it to the front (visible at top of handlbars) and its extremely loud and I can’t stop laughing. It won’t stay don’t worry, great for a laugh though.

[Architectonic]

I was originally going for nimh from rc cars but the temptation of lifepo4 was just too much. Has anyone ever had any safety issues with them like we do with lipo batteries? Lifepo4 seem so much more forgiving.
from

Here is some serious battery abuse from Liveforphysics:

The hacksaw test:
http://www.youtube.com/watch?v=8IBapfB0Imo

Puncture test:
http://www.youtube.com/watch?v=8IBapfB0Imo

More tests with various Lithium chemistries:
http://www.youtube.com/watch?v=dree0rTr1HM

[chopper_elec]

Haha thanks for the vids.

I noticed in my pics just then that I put the torque arm on the wire side. I also noticed there was no thread on the end where the wires come out lol.

Is it normal for the droputs to have some rounding in them at the very top? Just looks like part of the design. Not all the for out has this but I could rotate the axle a few degrees inside the dropouts.

Would it be more appropriate to put the torque arm on the non wire side?? I was thinking of running 2 but space is a bit limited on the wire end.

[chopper_elec]

Here is my rendition in 3D of how I was going to use the P clamps to mount the controller to the bike

[chopper_elec]

Big news everyone, i've decided to go with a rear hub motor kit that i've finally sourced from hong kong

Its going to be quite expensive but then again the wheel is quite uncommon

I'm looking at around $340 for the kit plus $140 shipping to Australia.

The benefits
- I will feel much more confident that the dropouts will be a bit safer.
- I have more space to mount a very decent torque arm on the rear
- The hub setup will be a lot less noticable on the rear
- It will look better

[Pedalex]

good to hear you´ve found one. i hope you ordered a fast woud motor for that small 20" wheel