Modded BOB 1000w motowheel buildout

JRA

Well-Known Member
When it rains it pours and I now fine myself embroiled in 3 distinctly different builds all of which I have had experience with in the past and hoped to re-visit some day but just not all at once!

A guy on CL had this modified BOB YAK up for sale at what I thought was a decent price considering the original cost and amount of labor that went into the modification that makes it very unique. He had two made and this is the last one the other he sold awhile ago to a guy back east and can be seen, unmotorized and used to hauil trail tools apparently as seen in the picture:
Screen Shot 2022-09-26 at 12.49.25 PM.png


And behind a bike:

Screen Shot 2022-09-26 at 12.49.55 PM.png


So the mod is pretty obvious in that now the wheel sits in the cargo space much closer to the rear axle of the bicycle. Should back up a bit and say that 10 years ago I slapped a 1000w Golden Motor on a BOB Ibex with a 12ah LiFePo4 duct tape battery in a nylon ammo box. All I had on the bike was a throttle and it handled just fine and would launch up steep streets too! I had a cooler that I got at the discount store that fit perfectly along with the ammo box to carry sundries in and go a ton of use out of it until one day it stopped working which coincided with one of life's jogs so it went un fixed and eventually got sold with the original wheel.

So plan for this one is a Direct Drive wheel, like the GM was and worked fine, for power like this:

Screen Shot 2022-09-25 at 7.49.18 AM.png


Also the stock wheel on a BOB is 16" while the modded setup is for a 20" wheel.

Ordered two 48v 10ah brick wrapped batteries with 21700 cells and 30A BMS that will mount somehow to the plates in the back which puts their weight behind the axle which should help with traction. Not going to bother with running them in parallel just will swap over the hot leads when one is done to the other for simplicity. Here is what I have to start out with:

Screen Shot 2022-09-25 at 5.40.12 PM.png


I have always felt after my initial experience with the BOB I did that a motorized trailer is a viable concept and has the ability to be adaptable to any number of bikes.
 

JRA

Well-Known Member
Got the batteries sorted and on order for the motoBOB and the FadBike. I am so glad I found, and quite by accident, such a good resource that will make whatever I can seem to dream up and are cheap about it to boot with fast shipping via air. 36v 15ah triangle battery for the bike and 2 10ah 48v ones for the trailer so that I can run them in parallel and use a double same discharge model that Herbert suggested. Reason for two in the trailer is that the mounts are in the rear and wanted to balance the load instead of one 20ah riding on one side. All batteries have Samsung 21700 50E cells and are wrapped, not in a case. I have an idea on how I want to carry the 10's using nylon ammo cans, of which I still have the one that used in my original motoBOB to hole the 12ah LiFePo4 duct tape one 10 years ago and hopefully can find another. I can fasten them to the plates in the rear and drop the batteries in and probably have room for a bag lunch!

Costs are starting to add up though as it was $602 for the order including paypal fee and shipping. So 35ah's total as well as the other parts on order but I think I am at the end of that trail and now just need to do the builds. I need to paint the BOB somehow and some color but haven't been able to nail down an idea on that yet. Too many options! Because I am in the big city for a bit I could get it powder coated pretty easily and am leaning towards that route. That or rattle can which is my usual MO when I am at home.
 

JRA

Well-Known Member
Progress report: Got the BOB back from the powder coaters. Went the bright route obviously. Wheel is in transit and batteries/boxes in stock.

BOB.jpg
 

JRA

Well-Known Member
Slow going but have most of the parts here to complete. I have another project, a christmas bike for my daughter in law, that is my focus right now as well as keeping my main steed in good form. Just got done doing a drive train on it actually and heading our for a ride.