Homemade electric bike, help needed with controller

[audipiglet]

hi all, I have been wanting to make my own electric bike for a while now but not to sure about what controller to get,

I want to keep the cost as low as possible and I already have a motor which is 36 volt, 800 watt, 28.4A and 2800 RPM
here is a link to it on ebay
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170645976022&ssPageName=STRK:MEWAX:IT

I have found this controller on e-bay and was wondering if it would work with my motor,
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=320569365271&ssPageName=STRK:MEWAX:IT

and was going to use these batterys, 3 x 12v 15ah
http://cgi.ebay.co.uk/3-x-LUCAS-12V-12Ah-15Ah-Batterys-Electric-Bikes-/180693042109?pt=LH_DefaultDomain_3&hash=item2a122503bd

If not could anyone point me in the right direction.



thank you for any help

 

[SamTexas]

The controller is for a brushed motor, so should work fine with your brushed motor. Those SLAs should work fine too.

Lowest cost possible, you're going in the right direction. Cost aside, your set-up is far from ideal.

 

[audipiglet]

Thank you for helping, what exactly isn't ideal and needs changing? I'm not good with electric, so any info would be great!

 

[spinningmagnets]

The bigger question is how much is your budget? If you can accurately assess that, we can make suggestions based on past experience as to what things you will likely want to upgrade in the near future. By upgrading now, it will save you some expense in the long run.

You will hear many suggestions from many people, but I am of the philosophy that since the battery will have to be replaced eventually (when it wear out) that the battery is the best place to compromise during the initial purchase. In spite of that, I recognize that an upgraded battery will provide you with the most suddden improvement in your E-bike experience.

A lighter battery will improve handling every foot you travel. A smaller battery will be easier to mount and/or carry when removing. When a Sealed-Lead-Acid (SLA) reaches the halfway point in its Depth-of-Discharge (DoD), the voltage will sag badly with an immediately felt reduction in performance (acceleration and top-speed). Plus any use of the battery past the halfway point will dramatically reduce its life to the point where it will no longer hold a charge.

The rising cost of Nickel has made NiCD and NiMH no longer desireable. The lowering of price for Lithium based chemistries has recently made them the most desired choice for E-bikes. However I don't recommend LiPo for new users, and that leaves LiFePO4 and LiMn as the current common upgrades. Both are expensive, which makes SLA an even better choice for starting out. (although when selecting the aH size, Lithium allows you to get a battery that provides 90% of its rated capacity, rather than only 50% for SLA)

A lose wire or shorted BMS on a Ping LiFePO4 can ruin a $600 pack, so you should exercise care and do a lot of research before commiting to something. Make sure the battery has an adequate C-rate for your performance needs so the pack is not stressed and will last a full life-cycle.

Spending a lot on a 36V Ping feels good, until you realize after a while that you would have really been happier with a 48V Ping (or 72V?). If your budget allows it, My most desired is a LiMn pack, but you may need to get a larger and more expensive pack that the actual miles of your commute, simply to have an adequate C-Rate (Current output capability).

If your motor and controller are getting warm, they are properly sized for the job you have given them, if cold they are bigger and more expensive than neccessary, if hot they are too small and will likely fry soon. A properly sized system will last for decades.

 

[SamTexas]

spinningmagnets is right about the downsides of lead-acid battery.

Your motor choice is not ideal because:
1) Brushed motor is less efficient (consumes more energy for doing the same work). Will not last as long because the brushes will wear out. Is not as quiet because of the physical brushes' contact.
2) More complicate to install compared to a hub motor. With the motor you chose, you would have to add a new chain and a new sprocket/freewheel somewhere. With a hub motor, you simply change one of your wheels.

If you do go the brushless route, you would also need a brushless controller. Take a look at this used combo for sale in the UK (I assume you're in the UK). It looks good and is just about as economical as your current planned purchase:
http://endless-sphere.com/forums/viewtopic.php?f=9&t=28702

I don't know if it's still available, and no it's not mine and I don't know the seller either.

 

[torqueon]

Thank you for helping, what exactly isn't ideal and needs changing? I'm not good with electric, so any info would be great!

Hey my bike is similar to what your trying to do. Brushed motor and 80 amp controller from Ebay, and I started with lead batts ! and up graded to life po 3 x the range increase. The bike has been reliable and meets many of the claims here on E S as far as performance and range. Lead acid batteries do suck, but are cheap and simple, but not a bad choice if electronically challenged.

I am not disputing all that been said above. My bike was built before I read up on endless sphere, Certainly I would of built differenty had i known what i have learned here. Since I managed to gear a 4800 R P M motor to run 26 M P H on flats, my next build with the famed R C motor will be easier with whats been done already !

I will say this type of build require's skills and facility's ! Chain alingment, jack shaft etc. Hope this helps.

For ideas check out non hub drive and your creation, threads. My bluid is listed as, craming 24 headway's into triangle.

When your up and running you will love it and be hooked

 

[TroyO]

I haven't used that exact controller but I have used a smaller one from the same manufacturer... it was a 12V/20A controller I use on a power feed system for my milling machine. It powers a cordless electric drill motor.

Not a single issue with it yet after several moths of regular use.

 

[audipiglet]

I wanted to use this motor because I couldn't find anything bigger than 250 watts in a hub motor and I wanted to go quicker than 15mph, (hopefully 25mph on the flat) and the range needs to be 22 miles, that was why I chose the batteries, I read you need 1ah to go 1 mile with a 36v motor,

 

[SamTexas]

There are plenty of hub motors with a rating higher than 250W. And the 250W hub motor in the ads I showed you earlier can be run at higher voltage to generate more power and speed. Anyway, good luck and have fun with your build.

 

[TopCat]

hi all, I have been wanting to make my own electric bike for a while now but not to sure about what controller to get,

I want to keep the cost as low as possible and I already have a motor which is 36 volt, 800 watt, 28.4A and 2800 RPM
here is a link to it on ebay
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170645976022&ssPageName=STRK:MEWAX:IT

I have found this controller on e-bay and was wondering if it would work with my motor,
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=320569365271&ssPageName=STRK:MEWAX:IT

and was going to use these batterys, 3 x 12v 15ah
http://cgi.ebay.co.uk/3-x-LUCAS-12V-12Ah-15Ah-Batterys-Electric-Bikes-/180693042109?pt=LH_DefaultDomain_3&hash=item2a122503bd

If not could anyone point me in the right direction.



thank you for any help

I have been looking at that very same motor on ebay and was ready to buy it last week but choose to buy a set of saddle bags instead for my chopper. Im glad I didn't buy it after reading this thread. I'll keep hunting for a 36v 1000w motor.

If your motor and controller are getting warm, they are properly sized for the job you have given them, if cold they are bigger and more expensive than neccessary, if hot they are too small and will likely fry soon. A properly sized system will last for decades.

Humm!!
Thats whats happeing to my motor when I run my bike? ---Hot -Hot Hot. So hot it'd take the skin of your hand. I must have some something wrong some where

Regards
Tom