My first ebike conversion completed

[Kepler]

I really thought my first conversion would be an RC style build but after testing a few higher performance hub motor setups, l decided to take easy path and go with a nice robust hub motor setup as a first bike project.

Nothing too revolutionary here I am sure but I have tried to select quality components and add a few of my own touches. Donor bike is a Merida TFS500 hardtail mountain bike with hydraulic disc brakes as I figured stopping was probably a bigger priority then the drive setup. First job was to upgrade both discs. These were replaced with 9" front disc and 7" rear disc.

I wanted better then average performance and as such went for a Crystalyte 408 hub motor, 48V/48V Crystalyte controller, and 24 Headway cells to provide a 72v supply. I looked at a 5000 series motor also but felt it was just too heavy for this sort of setup. I’m glad I stuck with the 408 as its got plenty of go on 72V.

The Headway cells are good but they are bulky and are difficult to mount in the triangle so I went for custom rear mounted box. The box is very robust and can be removed in 30 seconds by un screwing the large threaded hand wheel at the front of the box assembly. It also has a hinged lid allowing for easy removal of the 2 x 36V packs for charging. The box canter leaver's off the back of the frames and then has some added support through the quick release stainless steel catinery cables attached the back of the seat.

I really didnt want to loose my standard mountain so I have made the components as modular as possible and as can convert the bike back to standard in less than 5 minutes.

So that’s the completed project. Next item on the addenda is Cycle Analyst. Also might look at doing a light 72V 5ah Lipo setup mounted in the triangle for a bit of short distance work.

 

[floatingdog]

Very nice!

 

[nicobie]

Nice battery box. What did you make it out of?

 

[Kepler]

The box frame uses 25mm box aluminium with a 2mm aluminium plate to support the actual packs. The sides are 6mm acrilic sheet and the top is 1.6mm aluminium. Here a picture with one of the 2 packs sitting in the box.

 

[Bobocop]

Nice, and you still have room if you decide to add more batteries, i like the way you angled the box (instead of just making it a plain square box) makes it look nice.

 

[Kepler]

It runs two of those packs in series for a total of 72V so the box is completely full. I tried to follow the lines of the bike with the box shape. I think it came up quite well but its a lot of weight over the back wheel.

I have just tried a 22S 3ah LiPo setup. With only 2Kg of batteries and 90V on tap,boy the bike felt good. I am thinking 24S 5ah LiPo mounted in 60mm quick release tubes mounted in the triangle might be a good compromize. Should be good for about a 25Km range still. Just need to confirm if the controller can handle 100V hot off the charger.

I can see this new hobby is going to cost me a fortune

 

[dogman dan]

Might make some of it back selling those nice boxes and racks. Seriously, that's a big improvement compared to a standard rack with a trunkbox mounted way up high.

Very, Very , Verynice.

But... I don't see any bms there, be carefull.

 

[Kepler]

Thanks Guys, I appriciate the comments.

Dogman,

So far no BMS installed. still playing around with cell configuration and to be honest, I really want to avoid a messy BMS on board. I built this box so I could easily remove the two packs for bench charging and then use my RC chargers and balances to charge the packs. I am finding the cells hold their balance quite well anyway and as such only balance charge them around every 5th charge. I do run the multimeter across each cell before and after each charge though just to make sure.

Being new to the whole ebike seen, I'm on a steep learning curve but have pleny of experience with LiPo managment through many years of HV RC Helicopter flying. I understand the convienence of a BMS but for me, I think I will manage my Headway packs in the same way I manage my LiPos.

 

[MitchJi]

Very nice!

 

[pwbset]

Also might look at doing a light 72V 5ah Lipo setup mounted in the triangle for a bit of short distance work.

Sweet rig! I know the Bosch fatpacks have got up $20 or so, but they still make great little "to town and back" setups that can deliver 1,000+ watts sustained (which is in itself pretty badass) and have about 80wh useable. I used to use a single fatpack with my 504 to make quick full throttle town runs about 2mi round trip no problems. You'd likely need 2 in series though as under that much load for a single pack you'll hit your controller's 29v LVC if you're not careful and that would get annoying.

 

[dogman dan]

Shoulda figured you were new only to ebikes, not the batteries. The build quality shoulda tipped me off. A cell level lvc is good for us more ignorant types.

 

[Kepler]

Hey Dogman, hope I didn't come across a little arogant in relation to the battery thing, that certainly wasnt my intent. I have been lurking around this forum for a couple of months now and given the search button a real hiding. Picked up a heap of great info and really appriciate to help to date. I am a Mechanical Engineer by profession and have been an aeromodeller for near 30 years. With this experience, hopefully I can provide some useful contribution to this forum .

 

[dogman dan]

I would think so, and Welcome.

 

[MitchJi]

Hi,

I really want to avoid a messy BMS on board. I built this box so I could easily remove the two packs for bench charging and then use my RC chargers and balances to charge the packs. I am finding the cells hold their balance quite well anyway and as such only balance charge them around every 5th charge. I do run the multimeter across each cell before and after each charge though just to make sure.

You might want to consider getting 3 (or at least 1) CellLog8. Much easier than checking each cell with a multimeter and if you have 3 in place on your bike they will provide additional protection:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=12815

Some comments and a photo by "Doc":
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=15247&p=228528#p228365

BTW, the Great Celllog8 you just discovered was also discovered by some of us in the past somewhere around september and we have made a great review on it with some video on youtube. This is a really great device for the price.

 

[Kepler]

Thanks for the headsup on that one Mitch, looks like a good solution for a 3 x 8S setup. I use a similar device for my LiPo packs.
http://www.hobbyking.com/hobbyking/..._Cell_Voltage_Monitor_2-6S_Lipo_(New_Version)

Not quite as sophisicated but nice and cheap at only $12.95 a unit. Monitors 6s and alarms if any one of the cells drops below the set value. Set value is adjustable from 2V to 4V

 

[Kepler]

Here are a few shots of the new configuration using LiPos instead of the Headways. I have tried 2 types of tubes, one being 65mm PVC and the other 60mm postpack tubes. The postpack tubes are surprisingly ridged and saves 1/2 kg over the PVC system so I might go with the Postpack setup for now. They are both covered with a contact vinyl which gives the post pack a bit of resistance from the weather. I am trying to source 80mm heat shrink for the tubes which would be ideal.

Each tube weighs 1500g with the packs installed so there's not much stress on the water bottle blind nuts. Also the actual weight of the tube is taken by the bottom of the vee so it's only a bit of lateral load the drink holder anchors have to deal with.

Still running 22S 5ah for now as I haven’t decided if 24S is worth the risk to the controller. 22S at a usable 4ah (80%) is good for around 330wh which should be good 30km of managed riding.

So this setup has pulled 7.5kg off the bike and lowered the COG considerably. Now the bike doesn’t want to fall over very time l lean it up against a wall and except for peddling up hills unassisted, feels like a normal bike.

Total weight of the bike is now just over 20kg ready to ride. 85V on tap and top speed of over 60kph in a platform that stops as hard as it goes and handles. For a cross country/road rider, I like this setup a lot.



Cheers

John

 

[Kepler]

The project continues. I wanted to better utilize my Headways cells so I decided I would set them up like my RC LiPo packs. Rebuilt them in a 6S config complete with balance leads. This gives me a lot more options on setting up the bike and can add a subtract packs depending on what riding style I feel like on the day. The wiring loom is set up for up to 4 series packs with a jumper used in any unused connector to complete the circuit. This means I can now use my standard RC charger and balance charge 2 packs at the same time at 8 amps which give me a pretty decent turn around time of around 2 1/2 hour for the Headways (4 packs) 1 1/2 hours for the LiPo's (4 packs).

So now I have a nice mild 36V config for riding with the kids right up to a 4 x 6S (24C) LiPo config for silly speeds. The setup isn't quite as neat as before but I think the versatility makes it worth it.

 

[TMaster]

Wow this is a great setup! Very clean!

 

[Kepler]

Made a few more alterations to the bike. Now replaced the controller with an 18fet 72V Crystalyte controller. Moded the controller to handle 100V (thanks methods) Fitted switchable voltage ranges so I could still run a 50V setup when I wanted to . This switches both the LV power resistors and LVC to the correct range through one double gang switch.

Fitted a Cycle Analyst and also fitted a 3 speed switch which 1 think the 100V system really needs. Tidied up the wiring to finish things off.

Not sure how long the 408 will survive but so far so good with the motor still staying cool with normal riding speeds and a few 6 kW bursts for a bit of fun.

Easily getting 40km out of this setup riding as fast as I dare together with light pedaling. 10 whr/km is my normal riding target and is quite easy to achieve with this setup.

Here are some pictures of the latest setup

 

[graemebc]

Nice, like the look of that allot. I'm a sucker for dark grey. Clever use of space & different setups.

 

[Mark_A_W]

It's a very neat build, very nice.

100v? Crikey, you will need to be careful, if you are pushing 40+A through the 408. BigH cooked his 408 at 72v and 35A I think.


I'm going to use the Crystalyte 3 position switch with my Infineon controller too, pity they labelled it LHM...


Your brakes and shifters look a little...shifted. Are they usable like that?

The best solution I found for running front and rear derailleurs is to use Shimano Deore XT combo shifters, but they make brakes a problem - if you want hydros you'd have to stay with the Shimano hydro brakes.


We will have to catch up, when I've got my new bike running, shouldn't be too long now.


Mark

 

[voicecoils]

That handlebar setup looks very familiar! I'm stuck with having my half twist throttle in the same position too. Have you considered moving your 3 speed switch to the left hand handlebar to give yourself a bit more space?

Wrapping my hands around to get to the trigger shifters already feels a bit unnatural, add the 3 speed switch and I think it would be even tricker.

 

[Kepler]

It's a very neat build, very nice.

100v? Crikey, you will need to be careful, if you are pushing 40+A through the 408. BigH cooked his 408 at 72v and 35A I think.

I have seen 6kW so the poor 408 is no doubt on the ragged edge. I only use the full power for short 5 second bursts so hopefully the motor will live for a little while.

Your brakes and shifters look a little...shifted. Are they usable like that?
Mark

Brakes arn't compromized at all so that good but the rear shifter access is not ideal. Doesnt worry me too much though as I dont use the gears too much with this much power on tap.I can still change OK though but I tend to just leave it in top most of the time.

We will have to catch up, when I've got my new bike running, shouldn't be too long now.

Mark

Sounds good. Look forward to it.

 

[Kepler]

That handlebar setup looks very familiar! I'm stuck with having my half twist throttle in the same position too. Have you considered moving your 3 speed switch to the left hand handlebar to give yourself a bit more space?

Wrapping my hands around to get to the trigger shifters already feels a bit unnatural, add the 3 speed switch and I think it would be even tricker.

Actually fitting the 3 speed switch made no difference in getting to the trigger shifters so that good. The 3 speed switch molds in with the throttle so I think I will leave it there for now. But you are right about the unnatural feel on the trigger shifter now. I think its an acceptable compromize though.

 

[Mark_A_W]

Well, if you aren't using the gears that much, then an alternative is to ditch the front shifter, and use a twist shifter fitted upside down to the LH handlebar end.