WORX.VOR.EMC.v3.3

[Stevo]

It's been a while but I finally have time to sit down and edit some pics and write up the new and improved v3.3!
What's new?
1) modified frame/batt box mounts
2) newly designed and much lighter motor mount plate
3) newly designed BattBox
4) addition of Thunderstruck BMS
5) newly designed dashboard with camera hole cutout for my phone's camera


I changed the battery box using Harbor Freight pelican box knock-offs. I was hoping to add two more cells to 26, but ended up keeping it at 24, simply because the Thunderstruck BMS allows 24 cells. To add more cells was another expensive module, which would allow 12 more cells. Not really worth the expense just to add 2 more cells. I'm sure the boxes aren't waterproof, but a bead of silicone should make them fairly weather proof.
They don't look too ridiculous IMHO. They are big enough to squeeze in all of the electrical components (main fuse, contactor, hall sensor, Cycle Analyst shunt) along with the cells. Deciding where to put all of the cable/wire pass-throughs was a challenge. I also added some frame sliders to the design, to help protect the battboxes when I crash
I was also hoping to lighten up the bike a bit... It now weighs in at 419.6 lbs (190.3 kg) ... still too heavy!

I wasn't using a BMS before because there weren't any affordable options yet. I was manually balancing the cells, and this mod is truly worth every penny to simplify life!! For under $500, the Thunderstruck BMS is affordable and works very well. I splurged and bought the touch screen display too, although it isn't necessary for the BMS to operate. I'm quite happy with this new addition. The display makes it super easy to monitor each cell during the charging process. I highly recommend this product.

Now, the PICTURES!!

First, the battery box...

The center box bolts to the frame slightly differently then before. The motor mount bolts directly to this box also. It's a very rigid design. I don't feel any frame flex while riding. The coolant pump is also attached to it, seen just under the front fender.


Here you can see the new motor mount plate and the right side battbox holding plate, mounted without the battbox attached.


Here is how the pelican box knock-offs look when they are attached to the mounting plates.


Installing the Rt side battbox.



These pics show how the contactor, hall sensor and main fuse is securely stuffed into the box, using dense foam rubber (3 lb density closed cell foam).
This is the the Rt side box, the pack + side.


I constructed the the pack with thin rubber sheet in between each cell, and 1/8" thick silicone sheet between each set of electrodes. I'm confident there will be no arcing between cell pairs. There is some debate regarding separation of cells with metal sheet to contain a "run away" event.
My pack is divided into 3 compartments, 9 cells in each side box, and 6 cells in the center box. I conferred with Patrick, who I bought the cells from (theFREElaker here on this forum) and we both agreed that the extra complexity wasn't necessary. Time will tell

[Stevo]

The left side box is the pack - side. It has the shunt for the Cycle Analyst installed directly to the cell's electrode.



Here are a few pics of the left side of the bike before the left battbox is attached. I don't have any pics showing the inside of this compartment.
There are 6 cells ziptied together and squeezed into a foam rubber lining. Its a tight fit because the foam has to compress the stack of batts.
The ziptie helps to pull the stack out, which isn't easy.

Here are pics showing the bike finally finished (again)!:

[Stevo]

I think it's a functional work of art!

[flo]

Hi
good to see you still tweaking an already functioning bike.

As you mentioned you wanted to lighten it:
Would it not be possible to get 3 more cells into each box on the sides and thus get rid of the one in center?

greets

flo

[Stevo]

Hi Flo
Nice work on the SACHS

The cells are "compressed" with a 15mm thick layer of dense foam when the box lids are closed. They need to be compressed slightly.
There is only enough room left to add 2 cells max to each box. The center box is structural and needs to be in the design for rigidity.
Maybe when the next gen solid state batteries are manifested I can start tweaking again and use this space for an onboard charger and some of the electronic components.

But I'm done tweaking this bike for now. I now have plans to learn how to make a solar charger and building a solar charging bike port is on my list of next projects.
I will start a new thread on this topic when I get closer. I have a few other unrelated projects I need to tackle first before I start this.

[Spoonman]

I think it's a functional work of art!

I see what you did there.

[Stevo]

UPDATE
So after a month of daily commuting, and changing the drive sprocket down one tooth, I'm getting about 32 miles before I notice reducing power.
Thats going with careless bursts of acceleration to 80mph just for $hit$ and giggles
I plan on getting 4-5 years out of these batteries... and hopefully solid state batts will be around by then. I'll retire these into a solar charged power bank.
I'll start a thread on building a solar charger when the times comes... but I have to move first.
Ciao!

[Stevo]

ONE YEAR UPDATE!!



So much has happened in the last year, where do I start?
I have logged 1000 miles just commuting to work. I used to get around 35 miles before I noticed battery degradation.. but it still had reserve range. Just a noticeable notch down
in performance. The cycle analyst shows 43 charge cycles, some of which were during testing. So an average of 25 miles per charge is not correct. I usually charge when the cells get down to 3.4-3.5 volts
I changed out the front tire knobby for a dual sport tire and range shot up to almost 40 miles before I notice the battery getting tired. So I'll be putting this on soon:



I had one catastrophic failure early on. The main + Power cable to the Sevcon vibrated loose and turned, arcing against one of the three motor winding terminals.
That FRIED the controller. OUCH!
So after Travis sent me a replacement, I used these slick Nordlocks. They are a 2 piece anti-vibration lock washer in case you are not familiar.





Next, I had to move from my rental, so I followed in Andrew's steps and bought a fixer upper money pit to live in. All of my spare time and any extra cash has been going into house repairs ever since, but I love my home!

My next faiure that left me walking was a failed bearing in my chain tensioner



When it failed, the chain tucked the pieces into the sprocket and locked the back tire up. I removed the mechanism, reduced the drive sprocket another tooth and its been a great
tweak. I have found that this motor can be used with OEM gearing with no problem... Just run the same gearing you were using when still running the ICE



The skateboard wheels with the ceramic bearings are holding up very well for use as chain guide rollers



I will update again after I change the rear tire and get some miles on it.
CIAO!!

[flo]

Hi
thx for your update, on my sachs i have now near 2100 km on without a glitch.
Biggest thing missing still is a chain tensioner.
Would you like to elaborate a little about your design? It not obvious to me if or where there is a spring coil to keep tension.. and if so how did you find the right size? (lenght vs strenght)
greets

flo

[Stevo]

Hi flo
I should have used one of the skateboard wheels with sealed ceramic bearings for the chain tensioner, but instead I kept the original wheel that came with the tensioner, which I found on ebay. I have a spare one if you cant find one... you may need to modify it to make it work for you. Let me know and I will send you a pic.
I modified it by reversing the spring to push upward on the chain. It worked well until the wheel bearings seized. I was having trouble with the chain derailing, but after I reduced the size of the drive sprocket down to a 13 tooth from a 15, then 14, it doesn't derail anymore without the tensioner, so I removed it altogether and its been fine ever since. The bike is much quicker with the 13 tooth drive sprocket and gets up to 60-65 mph in no time at all...its very fun to twist the throttle.
I'm tempted to reduce the size of the rear sprocket to get a higher top speed, and to experiment how it would perform, but that would require more $$$ for a new chain, unless I can find a new master link somewhere.

I will shoot a short video after I change the rear tire and post.