Announcement

Collapse
No announcement yet.

Tern Electronode Cargo Bike

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

    Tern Electronode Cargo Bike

    In search of the ultimate city commuting mode,
    I came up with the idea of electrifying a Tern Cargo Node:

    I can ride it in the street, I can ride it on bike trails, if the battery dies I still have lights and can pedal home, I can carry two passengers, I can park it anywhere, I actually get some exercise everyday, since it folds I can take it on the metro during rushhour (not that would ever need too - since it is way faster to get around on this on the surface streets), I can pick up 6 full bags worth of groceries on the way home.
    It is as fast to get home in the evening during rush-hour as when I take my motorcycle and lane-split through the traffic jams (which is allowed in DC), and the thrills are on par. With all that POWER from the BBSHD I simply never even think about taking anything else to work anymore. It is so nice to just pass those long lines of cars that are travelling barely faster than the cars parked along side them.

    The Tern Cargo Node was $1800, the BBSHD kit and Shimano hydraulic brakes with cut-out switch and the C693 display from Luna Cycles was roughly $1200 with a 52V 11.5 Ah battery, Luna's adjustable charger and the Aluminium chainring adapter with 42 tooth sprocket. I also bought the programming cable so I could use Karl Gesslein's awesome programming guidance at https://electricbike-blog.com/2015/0...ing-the-bbs02/ .

    The other small changes I made to the bike we a set of more swept back handlebars, a touring seat with exhaust port, and oversized brake discs (225mm in front and 203mm in back) from Hope (because I hope they stop me good).

    I built the battery box out of Aluminum to rest the battery tall-ways on some rubber isolators on the Xtracycles lower brace bar, between the chainstays, then I made the grey waterproof cover from Rubber-duc FR18 vinyl (the FR is for Flame Resistant - not that I think it would do much against a lithium fire, but since it is right under my butt, and my seat has a hole where the flames could shoot right through and char my giblets, I will take all the FRs I can find).

    The 42 tooth sprocket on the Luna adapter work out great with the stock 8 speed rear, and I love the simple 3 PAS modes on the C693 as supplied (though you can change it to 5), which I I have set to ~250 watts on ECO, ~600 watts on TOUR, and full out is ~1300watts in BOOST. That is to say, you program the PAS as a percentage of the MAX AMPS and at 52V nominal, those are the watts I come to. I have the Max AMPS set to 25, not out of any concern for the controller but simply for power conservation. I also uninstalled the throttle when on my maiden voyage I drained the battery before the last big hill on my commute IN and was punished with having to pedal this corpulent beast home uphill and against the 15mph wind in 90 dregree 90%humidididity.

    After experimenting for the first two weeks after that, I came to these observations about the motor, the bike, and myself:

    A) - Changing the programming so that the motor does not step down power as you crank harder rewards me with great speed so I actually find myself pushing myself harder - going fast is FUN and that is the only motivation that works for me when it comes to exercise.
    2) - 250 Watts in ECO are actually quite sufficient, if I exert myself as I did when I was commuting sans motor, to pass all the athletic types and to foil the headwinds that plague my ride home each evening.
    3)- Though my time each day pedaling has been cut by 30%, I am riding my 22 mile commute everyday instead of just a couple of days a week. The time savings is a huge bonus.
    3.2) - at 600 watts in TOUR, with the 120lbft my fat butt provides each stroke, and in the right gear, I pull easily away from traffic at the stop lights.
    4)- at 1300 watts and energetic spinning on my part, I am climbing a couple of really steep hills at the speed limit, so cars are not even trying to pass me, which feels good and much safer.
    E)- I use approximately 6AmpHours to get to work and back, 22 miles total, using just ECO mode mostly, TOUR for the half dozen stoplight intersections, and BOOST just on 2 big hills and to blaze along with traffic on the one little parkway that cars go 30 ~35 mph on. Since I can time how long the charger takes at 3 amps to charge the battery to 90%, this seems the easiest way to measure "mileage"of sorts. This also means that I have a huge reserve, so if I ever need to make a side trip for any reason, range is not an issue to worry me. This also has me toying with the idea of getting one of the minicube batteries and another charger for work. Although for this bike saving 3 pounds is not a concern, but maybe on a second stealth bike build! Hnmmmmm...)
    6) - 24"balloon Schwalbs on a long bike handle really well and are comfortable.
    7) - This light the Tern came with works surprisingly well and is sufficient for lighting a curvy dark roadway far enough ahead when going 25 ~30 mph that I am not outrunning my brakes, if you get my drift. DEER! The light is Tern specific though, so this is just an observation for those considering buying one.
    8) - Good brakes are a MUST for a heavy bike. Even more so if you like to go fast. Cars like to hide behind other parked cars and are fast buggers - like deer.
    9) - I programmed the controller:
    - for a gentle power and from a standstill it still will spin the tire in BOOST when I stand on it to shoot across an intersection
    - so that it doesn't kick in until the pedal travel is twice the rotation as what it came programmed, because when I first installed it, trying to make a little forward adjustment while stopped red light, it nearly shot me into the crosswalk which was filled with ready victims minding their own business.
    - so that the power does not diminish when I pedal faster - great effort is rewarded with great speed! Something my factory chicken legs never could give me.
    - Having to pedal to go makes it very stealthy - some of our bike trails are heavily policed and they don't seem to notice I am going faster than my twiggy legs should be able to make a bike this big go, because I am sweating and panting so hard. The redness of my face makes it seem more believable too I guess.
    10) - TOUR, at ~600 watts, is plenty to keep from sweating in the hot summer weather and ruining dress clothes should you find yourself wanting to bike somewhere nice to lunch from work without having to shower again when you come back (another benefit to the extra range from the big battery in this case).
    Tern CargoNode with BBsHD Nice clean cockpit Working side of the concern Fresh air goes in, nasty air goes out...

    #2
    Update:

    I realize I forgot to mention more about the challenges in fitting the BBSHD to what is essentially a regular bike with an Xtracycle attached (though the way it comes from Tern for $1800 will the disk brakes and lighting and fenders and sidebags, it was a pretty good deal).

    ~I tucked the motor up high because I anticipated that with the extra long wheelbase going over bumps or curbs would allow the undercarriage to be way too close to the hard stuff - which turned out to be the right decision. Luckily the frame allowed it to come up really high.

    ~ the battery mount is basically riding on the lowest frame member - the bottom tiebar of the Xtracycle LEAP, between the chainstays, so the weight overall of the entire motor/battery set-up is not at all intrusive, unlike my other BBs02 bike with the Luna rack-mounted slimline battery, which is noticeable weight when maneuvering quickly. Not to say it is a huge concern, but the easy balance of my Cargo Node set up is great. Just great. For such a long bike, it sure zips in between the cars that constantly clog the intersections around here with a ballerina-esque grace.

    ~I had a problem with the chain jumping off the crank ring on overrun when I hit a hard bump at the same time I was downshifting, but that turned out to be because the original crank had a larger tall gear and I had not taken out the links in the chain to bring it to the right length. Once I had that figured out, taking out 3 big links worth, the problem disappeared, as did the iffy shifting under load. It is now very smooth and surprisingly quiet.

    ~I got the Luna chainring adapter because I thought I might need to change to another ring size, but it turned out the included 42 toother is perfect. And it matches the bike really well.

    ~I could not use the speed sensor because there are no harness extenders I would need to mount it to the long wheelbase, but the only repercussions of its omission are that the error code 21 displays constantly and the speed reads as 00, but that is fine, because at the speeds this thing goes I need to be paying attention to the road and not looking down for even a second. It has the bonus that the motor never cuts power because it thinks I am going to fast - it just keeps right on assisting!
    ~to that end, the 3 PAS levels of the c693 make it supper easy to never actually have to look down - It is very obvious which of the three modes I am in simply by pedal feel. I can truly keep all my attention on the road and world around me without the distraction of too many options for the controls I need to adjust. gears on the right hand, power assist on the left. I previously had a BBs02 on another bike with a 5PAS stock set-up and it was a distraction to constantly be looking down to see if I was in the one I wanted - human nature?- too much choice can be a bad thing? The upshot being I am going with the c693 on my next build as well!

    ~I bought some of black polyethylene spiral wire harness wrap to tidy up the entire control cable set and it works great, looks great (you can see it in the photo above of the business side of the motor): http://www.usplastic.com/catalog/ite...688&catid=1051. Since I had to buy so much, if anybody wants some, give me a shout and I can send you some feet you need for the price of postage.

    ~I found Karl Gesslein's programming guide and other advice very spot on and invaluable so I donated $50. He saved me many times over that amount by making his experiences and well thought out observations free and easy to get to ( such as his article on greasing, which I followed for both my BBSxxs and am very happy for the advice and results https://electricbike-blog.com/2015/1...and-not-heard/ ). I credit his advice for the very high level of satisfaction I have with my set-up now. His articles on how to program the controller are very well written. Thanks to him I am now intimately familiar with my BBsHD inside and out, much quicker than if I had waited for things to go wrong to do my research, and my confidence that I can fix my own mistakes (just being honest here - most problems are of my own making!) is much stronger.


    Other than all that, the bafang kits are super easy to install and the end result is a very clean looking kit.

    I am going to put a jump seat on the deck and got a pair of these: http://www.vigurvant.com/ so it will be the ultimate short-wheelbase-common-crank-v-twin-human-electric-hybrid ever. https://vimeo.com/81327766 c[^:

    Comment


      #3
      Nice build, love it.
      http://electricbike.com/forum/forum/...ictorial/page4

      Comment


        #4
        Update-ja vu:

        So I simply had to build another electric bike, being so happy and all with this little number, and so I sold a couple of my motorcycles.

        This is related, bear with me here, to this particular bike as you will see. So I ordered another BBsHD from Luna again, because, lets face it, they are the best deal in town, they have the best accessories, and by far the best source for batteries. Plus they put up with my wishy-washiness.

        So UPS decided that since I was not home to sign for the battery and Bafang box they left me a nice little note saying they are going to leave it at a drop-off point, the latino market up the hill a'ways. This was perfect, as then I could swing by on my way home after work and pick it up.

        Here we are, all loaded up for the ride home:

        Comment


          #5
          And here is the little off-road and uphill excursion shortcut home. I was in 3rd gear, in BOOST PAS, and standing up for a little better control, and this baby just rocked on up that hill.
          So far, none of this could I have done in my car or on my motorcycle... Fun.

          Comment


            #6
            And here we are at home: I will post the build as I go for the bike the new BBsHD is going on, which will be a belt-drive adventure, seperately when I start it this weekend, but for now here are the final observations on this ElectroCargoNode.
            Plugged in my Luna adjustable charger to the battery gauge my reserve voltage before plugging it into the wall for the evening's juicing. I left home with ~57.2volts, which is the 90% state of charge I have the Luna charger set at for the 52V battery pack, and after 26mile commute which included my side trip to get the new motor, I had 52.3 volts. On really hot or really windy days it has gotten down to 51V. The battery indicator on the c693 screen still showed full bars, which it does anyway until it suddenly goes to 3 and soon after 2 and 1 and then shuts down, so I use the Luna charger more as a meter of sorts. The other thing I do is time the charger, which is set at 3 amps, to get back up to the 57.2 that I left with, which is pretty consistently a 2 hour affair now that I have a routine of pedaling and assistance down that gives me the right balance of Fun, speed, heart-rate elevation, and muscle fatigue. So 6 amp hours, at ~52v, 4 days a week, gives me a consumption of roughly 5 kilowatt-hours a month. At $0.12 per Kwh we got ~$7.20 a year of electricity. Taking my motorcycle everyday costs roughly $190 a year in gas at $2.00/gal. This baby will totally pay for herself in like just 48 years! yay math.

            Comment


              #7
              Originally posted by Bernhardgrave View Post
              ... which will be a belt-drive adventure ...
              Hi - a few weeks ago you mentioned the special 28T Di2 rear sprocket used inside-out, will it be part of the mix?
              Click image for larger version

Name:	167236.jpg
Views:	1
Size:	75.4 KB
ID:	20676


              If I remember, this shifts 4mm, is that correct? I thought "we" needed 8-10 mm to get out where the Rohloff is. I've been wondering if an adapter could be fabricated (at least for axle-end-activated IGH hubs like the I-3) to fit over the cog stub on the hub, and extend over towards the frame with a threaded portion (upon which a rohloff centertrack cog would then thread).
              Click image for larger version

Name:	adapter.jpg
Views:	1
Size:	11.1 KB
ID:	20679



              A little like the way the 10mm cupped cogs work:

              Click image for larger version

Name:	599_p1.jpg
Views:	1
Size:	146.1 KB
ID:	20678
              2nd build, 2018 Crust Scapegoat, BBS02 or BBSHD, Rohloff IGH
              3rd build, 2018 Crust Evasion step-thru, BBS02, Shimano Nexus INTER-3 IGH
              4th build, 2016 Salsa Marrakesh flatbar frameset, BBSHD, Alfine 8 IGH

              Visit the forum knowledge base

              Comment

              Working...
              X