Cheapest conversion ideas for my 90's Rockhopper

[cajunjay]

I have been lurking on here for a few weeks and have finally decided to go ahead and convert my old Specialized Rockhopper to an ebike.

So many members here have built such outstanding bikes, trikes and everything else. There are hub motors, RC setups I just dont know where to start.


My aim is to be able to reach speeds upto 25mph with around a 10-15 mile range. Any suggestions would be much appreciated, I might even just buy a kit from ebay they seem okay for the price, about £200 delivered for a 48v 750w, 800w or 1000w hub motor with everything you need minus batteries.

 

[auraslip]

My aim is to be able to reach speeds upto 25mph with around a 10-15 mile range. Any suggestions would be much appreciated, I might even just buy a kit from ebay they seem okay for the price, about £200 delivered for a 48v 750w, 800w or 1000w hub motor with everything you need minus batteries.

Thanks for putting your goals out there! 25mph would be between 36v and 48v... probably more like 48v. That being said, I wouldn't get the ebay kits when other, better options are available.

http://endless-sphere.com/forums/viewtopic.php?f=31&t=14731 $250 shipped in the states - I got my first kit from here a year ago.
http://endless-sphere.com/forums/viewtopic.php?f=31&t=19971 $150 + shipping - pretty common - might be on the low end of 25mph though

For the battery the low range means you don't need a huge pack -

http://www.pingbattery.com/servlet/the-9/36V-15AH-V2.5-LiFePO4/Detail $450 - this is a common recommendation

Another option I'd recommend is a 36v 10ah a123 pack from cell-man - Probably $450 - it's smaller than the ping capacity wise, but very high c-rate meaning you could upgrade it in the future.

My first kit used a 36v14ah SLA pack (more like 8 useable ahs though) - speed was 23-25mph with a 15-20 mile range. It was only $100, but it weighed 30lbs and took 7 hours to charge.

I upgraded that as fast as I could

 

[dogman dan]

Not much I can add to that. Since you don't seem to be located in north america, recomending a ship from china vendor we trust is the way to go to keep the price down.

Our favorite vendor is ebikes-ca. Go see his site just for the educational value of it. If you had a big budget, paying a bit more for his quality of service is not a bad idea.

 

[cajunjay]

Hi guys

Been on here lurking around looking at various builds and have come up with my own but need advice on how to implement the whole setup.

Ive gone for a cheap build as these parts are all sourced from at shop not far from me except the batteries which will be from HB.

Heres my bike.



Uploaded with ImageShack.us

Motor I am going to use and controller.

http://www.petrolscooter.co.uk/catalog/product/view/id/8182/s/electric-motor-24-volt-500-watt-11t-6mm/
http://www.petrolscooter.co.uk/catalog/product/view/id/7110/s/speed-controller-500-watt-24-volt/


My main problem is how do I actually mount this motor onto my bike, I have seen many different variations but which is best/easier as Im no engineer. I know 24v 500w isnt really that powerful but I do plan on always pedaling at the same time.
I will be using batteries from Hobby King which work out to be 22.2v 15 ah will this be ok?


Thanks for looking

 

[NeilP]

Well if you are going for that motor and are not an engineer....good luck

If you want a simple solution go for a hub motor...order ready built in to a wheel from e-bikes.ca or one of the many other suppliers....or buy a complete kit from them

Drop the old wheel out, pop the new one in, job done.

if you plan on using the motor you link to, then you will need to make mounts, drive system, chain tensioners etc etc...a lot of engineering work if you are not mechanically minded

A kit like this

http://www.ebikes.ca/store/store_ezee.php

is easier

 

[Bluefang]

Your best bet to get a working Ebike that doesnt cause you alot of hasstle to get it right is to start with a hub motor, learn about the electronics side then start doing the mechanical stuff. Or if you want to build a E-bike on a budget and do some mechanical work you will have to do alot of reading to start with but Gwhy has build one of the simplest RC drives i have seen http://endless-sphere.com/forums/viewtopic.php?f=28&t=22245&hilit=son+inlaw&start=15 Another option is a friction drive, try searching for Kelper in the non-hub motor section to see what i mean.

That motor you have linked is not really worth the money you would pay for it, i am pretty sure you can get them alot cheaper on Ebay for the same thing too.

Derek

 

[cajunjay]

Thanks for the input guys.

I will go with a hub motor kit then to save hassle but first I will contact the guy you mentioned about thr rc drive unit which is what i actually want.

 

[cajunjay]

Hi guys

Im so glad I found this forum a few weeks ago, since then I have contacted a member on here who supplied me with most of the mechanical parts that I needed. Thanks mate 8)

I have the rear wheel sorted with a 65t go kart sprocket and a freewheel for pedalling. I have a jackshaft which works through bearings in a handlebar headset/stem. The motor will have a 16t pulley which goes to a 72 tooth pulley. This then drives the 16t go kart sprocket which in turn runs the rear wheel kart sprocket 65t.
The motor will be mounted onto a plate which has hall sensors attatched.

I have this controller 48V 350W brushless controller, I can upgrade this once its all running for a few quid.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=260511665860&ssPageName=STRK:MEWNX:IT

I have ordered a Turnigy AerodriveXp SK Series 63-74 170kv 3250w, 4x 5000mah 6s 20c lipo packs, 2 packs of connectors and a charger.

I have just ordered 2 meters of red and 2 meters of black 10awg wire and a karting chain.

I have a cheap throttle off ebay and a Turnigy watt meter.

So basically I got everything I need but is there anything missing like fuses etc for the hall sensors or anything like that, I new to all this its just a dream of mine to own an electric bike which hopefully isnt that far off.


Once I have everything in front of me I will lay it all out and take a photo so you guys can see everything!

 

[GrayKard]

Has that bike been wrecked? Looks to me like the fork legs are at a different angle from the head tube.

Gary

 

[gwhy!1]

Has that bike been wrecked? Looks to me like the fork legs are at a different angle from the head tube.

Gary

I think it may be just angle that the photo was taken from.

 

[cajunjay]

The bike is just fine works a treat and is fairly lightweight.

Not sure what you mean but maybe it is the camera angle!

 

[GrayKard]

The red line in the picture is as close to the head angle as I could get. The fork legs should follow this angle if everything is right. Did you buy this bike used because it looks like it was very well used.


I would be worried that a fork leg will come off.

Gary

 

[cajunjay]

There is nothing wrong with the bike, ive been using it for over 3 months without any problems at all.

I will just need help wiring it all up when I have all the parts in front of me.

 

[gtadmin]

The red line in the picture is as close to the head angle as I could get. The fork legs should follow this angle if everything is right. Did you buy this bike used because it looks like it was very well used...

It is quite probable that's camera angle, you can see the other leg quite clearly so I wouldn't draw any conclusions from this picture. If the camera angle was dead on and the forks followed your red line, THEN I'd be worried

 

[cajunjay]

Hi guys

Just wanna clear up once and for all, the forks are not damaged or broken they actually work really well.

Maybe the picture looks weird to you but its probably the angle. Here are a few pics just to show all is well!

 

[cajunjay]

Hi guys

Just got all my bits from HobbyKing, Ive tried getting the motor to spin with no luck. I wired up one battery to my fuse block and then to the watt meter into the controller, should the controller make any noises so I know its powered up at all?

Hopefully somebody can advise me as what to try next using the pictures I have taken

Thanks in advance

 

[gogo]

When you connect the second of either the positive or negative from the battery to the controller there should be a small spark at that connector. The spark is an indicator that the controller is getting juice. Some controllers have an "ignition wire" that needs to be connected to the (positive?) battery wire before it will output to the motor.

I see you have the throttle connected. It should have at least 3 wires, a positive, a negative, and a signal. When the pos. and neg. are connected properly, the signal wire should show a variable voltage of 1V-5V between it and the neg. when the throttle is twisted.

Do you have some sort of hall sensor setup?

[EDIT] You have a 48V controller which means it probably has a 40V low voltage cutoff. How many volts are you feeding it?

You have a 3 phase motor that will not spin until you have all the phase and hall connections sorted out properly.

 

[cajunjay]

Hi

Yes I have hall sensors setup also but not wired this part up yet, just want to get the motor to spin first then I will do the hall sensors.

This whole thing is not as straight forward as I thought it might be.

The power leads for the controller has a positive and negative wire and also another thinner red wire, so I just connect these two together ( the reds)

Sorry I sound a bit dumb but Im not good at all this

 

[wesnewell]

Found original post. Your 48V controller has a 41.5V LVC, So you need to connect 12s to the controller. It won't work at all with just 6s. Then you need at minimum to connect the phase wires to the motor. And unless that motor and controller will work sensorless, you will have to connect the sensor wires too. Once you have that done properly, the motor should work. Your controller looks to be 15A max. That's only ~700W (with 12s) it will put out to the motor which is rated for 3250W. I'm not an rc guy so have no clue as to how this setup is going to work once you get it hooked up right, but I suspect it's going to be pretty slow at 700W.

 

[Rassy]

GoGo mentioned the throttle, and it looks like the throttle is hooked up to the wrong wires. Probably the three wires from the controller that terminate in their own little connector are for the throttle, but I am anly guessing. Good luck getting it all sorted out.

 

[cajunjay]

Hi

The throttle wires are connected correctly as I took them out of there own little connector and connected them up myself using the diagram that came with the controller so Im sure the wires are correct.

I have 12s which shows 46.2v on the watt meter.

The hall sensor is connected to all the correct colours as shown on the diagram also.

Tried the 3 motor wires in every different combination but still nothing happens, really stuck here now as what to try next.

 

[wesnewell]

You should get a good spark when you connect the battery to the controller unless you are using a spark arrestor setup. I don't know what diagram you're going by but it could be wrong. Also, you might need an ebrake hooked up, or some kind of bypass jumper for it.

 

[cajunjay]

I have a resistor connected inside the anderson plug which then connects to the fuse block, so I wont really get a spark.

I was using the pixture I just posted up so I know which wires are for the throttle, sensors and motor but still no luck yet.

very frustrating trying to get the motor to at least spin

 

[ZOMGVTEK]

It will not work unless the halls are connected, has a input voltage greater than the LVC, but lower than a potential HVC, and has a throttle connected. According to the image showing the conntectors, there is a RED turn on wire that must be connected to the + voltage for the controller to power on. In your images I see two pairs of red and black wires... What do they do? You should question any wires you do not have connected, make sure you know what theyre for.

If you are SURE you are feeding the controller voltage within its specified range, and the throttle is working, halls are connected, and 3 phases are connected, I would open the controller and see if there is a status light on it. Generally they flash only once if all is well, and more rapidly if something is wrong. If its flashing at all, its probably OK and 'working'. If its flashing once, and slow, its probably not an issue with the power or controller. If its flashing rapidly, its probably a LVC or hall issue.

Just my guess. Its hard to tell without having experience with the exact hardware you are using. Also, to be perfectly honest, your wiring looks questionable in those images.

 

[FMB42]

I strongly suggest that you properly connect the controller, motor, and hall wiring before you power the system up. Doing otherwise is just asking for a system damaging short circuit.

BTW, that's some nice fabrication work on that motor mount.