Flysky i6 3D Printing parts

Hi, I'm starting to collect, design and gather some 3D parts for the flysky i6 transmitter. I will add them here with links as I get through them, please let me know if you happen across some cool things also.

Here I made a replacement cover for the battery compartment

The link is here

Also I made a Lithium battery holder so I can use rechargable batteries I have. The design is specific to the battery but you can use it as a guide for your own

Link here

:)

Ghetto ebike: Test Ride #1

So, now that I have my ebike built and setup I guess I should test ride it and show some stats. What better way to do this than with the ultra competitive online bullshit competition site Strava!

I can already feel the blast wave from your shock and gasps. Yes, I'm a massive cheat, etc etc. But this is a little bit of tongue in cheek humour and also a test of my ebike. What better way than to run it against the hardcore cyclists, who themselves run hidden motors on their bikes to cheat in competition? Who dope using epo just like the pros. That's right just like the pros themselves. And with that notion, I am doing nothing different than them... So sit back in your chair, unclench whatever part of lycra you are clenching and read my results.

This is my ebike by the way

It's not exactly a Pinarello Dogma

But this is what you increasingly see the Strava crowd riding on, waxing their bodies, trying to be as close to the marketing machine of professional cycling as they can possibly be. 

The question is can this ghetto ebike keep up? Can it exceed? Or does it fizzle out?


For my test I did a night ride loop, just totalling 9.7 miles as seen above. I barely pedalled, I could probably eat a donut or smoke a cigarette while did this ride. Physically, I felt no different when I finished, than when I set off. Except my ass hurt from lack of suspension. I may have to look into that. 

My maximum speed was 32.4mph. However I have ridden the ebike faster than this and got 35mph

So what kind of results do I get? Well I got the KOM (King of Mountains) trophy, by a country mile. These Strava riders clearly struggle with the uphills.

As you can see from the results I covered the 'mountain' (It's hardly a mountain, but a hill, reasonably challenging) and bumped every other rider by several minutes

Those carbon fiber clad losers need to pay more for the latest Pinarello model, clearly. How else can you win but by spending thousands of dollars on a bicycle and shaving your legs?

Interestingly, on the flats, and downhills, I am only just getting inside the top 10. I think a combination of my ghetto bike with pannier bag holding my sandwiches, creating wind drag, the limits of the motor, my wheel size, not shaving my legs, all these things are holding me back from the number #1 spot. Oh, and probably pedalling. Pedalling would probably help, but why bother?

When riding the ebike, the air roaring past your ears at speed, makes hearing more difficult, I wear a warm hat to fix this issue, it also keeps my ears warm and prevents ear ache. Also lack of pedalling/exertion means that you feel the cold much more, just like riding a motorbike does. Remember, I am here in the damp and cold of England. Riding the ebike at night is like standing naked in front of an air conditioner. (See Update on temperature handling)

Riding the ebike motor like this does make the motor unit heat up. It gets warm just like the motors on my quadcopter brushless motors. If there wasn't the cold air of England to provide cooling, If I happened to say, be in California, or worse, Nevada, then I am sure over heating the motors would be an issue at the speed I rode this ride. But, it seems to cope well here.

Things I notice about the ebike

Hmmm, One of the things that is noticeable is the throttle slider. It is either on, or off. I assumed that it would be more like a real throttle control where you can apply power as you increase or decrease the press of the slider. Another thing, is that I can exceed the rated wattage, according to the ebike display, I find myself hitting 1000 watts sometimes. And I am not too worried about the motor. I can 'feel' how it is performing as I ride. Or, at least I think I can... Also, I am unable to use the one lowest gear on my bike. If I switch to this 'granny' ring, the chain falls off. I could buy a special chanring to fix this issue, but I don't want to pay $200 just to allow me to use this single gear. I am in the process of designing a chain catcher to see if I can solve this issue for zero cost

Conclusions

Yes I know, I am a cheating sonofabitch. But try to see the lighter side of this. Right here, is the future of cycling. I mean that. This ebike system is going to take over our everyday lives. It has speed, it has range, I have 1 hour charging. These three things make a very very viable mode of transport. It's going to enable the poor, it's going to enable the less able. Commuting to work will be in your own hands, and no longer at the mercy of public transport delays. I estimate I can ride 60-80 miles on this ebike, and I will indeed perform a test to show this can happen. This ebike shows that you can choose to pedal if you wish to, or you can just cruise like you do in your car. The cost savings which include not having to pay out for mandatory insurance, mandatory annual MOT test, mandatory road taxation fees, and zero gasoline costs, makes this an extremely viable commuting option and is putting the cost savings back into the people's wallets and that is a good thing for everyone. One of the issues of motor car driving here in the UK are the annual costs as stated (insurance, mot, tax, fuel), collectively it is expensive, and prohibitive for the poor; we are talking paying the equivalent of the cost of a new car, every year just to be allowed to drive your car. If you can't pay, you go to jail. I like the ebike. It puts power and mobility into the hands of everybody, not just the privileged. You could of course just use a push bike, but the ebike enables those less able to. If the government outlaws the ebike, which I don't think it can do, there should be outrage and protest; It would signal to me that they desperately want to control a system of taxation, without considering the needs and upward mobility of the poor. I for one will be fighting for the ebike forever. Now, just how do we stop the rain?... 

Sorry to the Strava crowd for my test. I will be removing it from record soon. I must also emphasise that I do sometimes use strava legitimately on my pedal bike, and also have a few KOMs and number 1 positions. One of these pics I'm at the top of Mont Ventoux, and I didn't have to run.

Update #1: Ambient temperature & Motor heat

As I learned on my early test rides, riding the ebike in the UK is generally cool for the motor; It does not heat up and is not affected as much by ambient temperatures below 18 degrees Celsius/64 Fahrenheit. However, this week saw unusual UK temperatures due to a heat wave pushing us into 35 degrees Celsius/ 95 Fahrenheit. On my normal ebike grocery journey, one which the motor handles hills just fine in normal UK weather, keeping nice and cool and not overheating the motor, this week I noticed that indeed my motor was becoming much hotter. I did not have a thermometer available, however I predict that my motor was hot to the touch and an estimate of over 65 degrees Celsius. I predict that the heat was generated from pulling me up some road hills (2-3 hills of 300m @ 9% incline) on my journey. I also had some groceries in a bag, but no different than the same journey in cooler weather.

I can understand other people's reviews of the ebike motor and concerns about heat management based on the reviewers location. It is likely that the reviewer is testing in a hotter environment than me. However, I would recommend research into cooling systems for ebike motors to help with this, after all, electric cars have cooling as do home computers. Selecting a lighter gear ratio for your ebike would also probably help generate less heat in a hotter environment.

Anyway, just observations and writing. Here's my idea for a cooling system

Ghetto ebike: Charging

I would like to show how I am charging my ebike battery packs. In the Electric Vehicle (EV) world, developments in battery charging means that we can now recharge vehicle batteries in a short amount of time. 

With charging systems such as on a Tesla car with huge batteries which weigh a whopping 544KG, for the Tesla to achieve a rapid recharge in around 80minutes it needs to also use a massive charger like the 'Tesla Supercharger' station seen above. Big batteries need Big chargers, and this is exponentially matched if you wish to recharge within this short time frame.

The same is true for ebikes. If you wish to recharge in a short time frame, you need a decent charging station, albeit modest when compared to the Tesla Supercharger. At the moment, there are limited options for an ebike owner to buy a packaged system from a retail company, and the price is also suitably matched (high priced) from these companies. If you google ebike charging station you get a whole host of Utopian-idealist dreams.

As we stated above, the Tesla battery weighs 544kg, my ebike battery weighs 3.8kg.

This is where a spot of DIY can save you lots and lots of money. In the Hobby Remote Control world it is well known that people make their own systems for quite small amount of cost. A popular solution is to use PC computer power supplies and connect them to a charging controller to supply the battery with a particular pattern of charging depending on its capacity and chemical composition. What this means to you and I, is that we can use this same system (with a little know-how) and have our very own ebike/Tesla Supercharger in our own home.

Here is my ghetto setup

I am using two cheap (but powerful) 12 volt power supplies taken from a computer, they have been wired in series to make 24 volts. Then, they run to a charging system which can be set to match your battery, in my instance; two 24 volt Lithium batteries with a capacity of 16ah. Together they make a 48 volt battery to run the ebike motor.

A little bit of test observation for the Turnigy Reaktor 300W charger, charging the 16000mah 6s batteries, the charger is capable of charging at just under 13 amps. A more powerful charger and we could charge the batteries at the 1C rating of 16 Amps, but that of course would cost much more money for such a charger. For example, the icharger 3010B puts out 30amps/1000Watts (£160), Turnigy Reaktor 30amp/1000Watt (£100). More on the Junsi range here.

For my budget, I am okay with just-shy-of 13Amps charging. Maybe I will test other chargers in future. Charging the ebike batteries takes my charger approximately 30-45minutes each depending on how depleted they are. 1hr 15mins from 'flat' (3.2v per cell).

My Power Supply unit could easily power two chargers at the same time. Probably four or more at the same time.

(China charging station)

What this means to you and me is that I can recharge my batteries just like the Tesla supercharger, and in around 1 hour I have a fully charged battery ready to ride again. This is how the DIY charging station is going down in Shenzen China. Retail systems made by companies seem to be pricing around £2000 just for recharging systems. If you want off-the-shelf stuff you will pay about £500-600 for a 1-hour charging station. DIY is much much lower cost, but you have to know what you are doing, and most of us don't.

Of course we can also recharge slowly using cheap chargers, which will be suitable for 12-hour overnight charging, and these can be had for modest amounts. But if you wish to be a DIYer you can have a 1-hour supercharger for just a little bit more.

Ghetto ebike: Wire Harness and things

I wired up a battery harness to connect two 24 volt batteries together, creating a 48 volt battery. Here is what I used:

2 x Male XT90 connectors
1 x Female XT90 connector
10AWG wire in Black & Red
Some pieces of 6mm Heat shrink tubing

Wiring it together is straight forward, you have to take note of the correct soldering as seen here

I recommend considering the use of anti-spark connectors for the motor connection. They can be bought here cheaply.

Powering up the ebike is a nice result after all that planning. It works! The colour display has nice information, not just clock and speed, but also displays Watts so you can see if you're pushing the 750Watt motor too hard (The motor will heat up). I have 9 power assist levels, and find anything past level 5 to be a thrill ride. The throttle control also lets me cruise without pedalling. I overtook a lady on a steep hill yesterday, she was gasping for breath at 3mph and I roared past at 25mph glancing back at her 'I hate you' smile. People gaze at me as I ride past - I notice that they are staring at the lipo packs mounted on the frame trying to figure it out. I may have to cover them and make them less obvious.

One thing I wish I had was manual adjustment of the pedal assist maximum speed limit. I can set it to one of three settings 15kph, 25kph, or 45kph however, I think I would like to set this manually to suit me, as I find my natural bicycle riding pace to be about 18-20mph and I find 25kph/15mph a bit disheartening when I have to pedal normally without power assist once I have passed this speed. I'm sure there will be commenters saying that 15mph is the law, but I'm cycling naturally at 18-20mph, I always have done. I'm quite a cyclist with years of riding. I once rode over 3500km from my home in Manchester to Naples in Italy camping every night at the side of roads and in fields. I have several bike tour experiences.
*Update: it does indeed let me adjust manually the assist mph/kph in single digits. All is good.

I am waiting for a power supply for my lipo chargers to arrive then I will probably do a full test of range and the display performance. All in all I am happy with the motor performance. I would like the chainring issue to be solved - I will 3D print a chain roller guide this weekend, and the Pedal assist limit to be changed. Those are my only gripes so far.

Ghetto ebike: Batteries & Mounts

Hi, I finally got round to designing and printing off all the mount parts I needed to allow me to mount the big batteries. Here are some pictures

It was actually more time consuming than I realised to design and print. Each mount took approximately ten hours each to print so I just set it to run and run while I went out to get bolts and screws. I'm really happy with the way it came out, the measurements were pretty much spot on for the tubing, and the bolt holes worked - I used hexagon holes at the back to help tighten the nuts without having to use a tool to tighten there. The batteries will be held over the top with straps, and there are some foam pieces for support of the batteries. They are held really tightly. I ended up using PLA as a print material and I am happy with how strong it is.

Fitting the Bafang motor set was fairly straight forward, I had no difficulty, I had all the tools needed. There is a nice guide to fitting the motor here:

I do recommend getting a 'Hollowtech II' spanner to help you to tighten the lockring for the motor. The only issue I had was that I cracked the plastic bottom bracket cup when removing the old unit but it was easy to saw through and remove once I had the thing removed by unscrewing the other side. I recommend looking up a video on youtube to help figure that process out.

I think, all that is remaining for me to do is solder a Y-harness to connect the batteries to the motor (in series 2 x 24volt batteries = 48v) which I will do after a cup of tea.

One issue I face from the setup is the notorious 'chain falling off' problem. I took the bike for a test pedal to check the brakes and gears, and of course the chain falls off the motor ring when trying to use the top two gears at the back. I didn't know about this before searching on the internet. There are discussions here here and here.

It seems that the BBS02 Motor has been designed with Hub gear units in mind, and not in general traditional multi-cog cassettes. Hub gears mean that the chain will not move up of down when shifting gear, it will always be in one position. By attempting to use standard cassette gear systems, the BBS02 has a flaw where the chain will fall off, usually on the upper two gears due to chain alignment issues. There seem to be people who have already experimented with solutions, and these range from a complete front chainring replacement (around £100), using a hub gear as mentioned (Anywhere from £300 to £1500), and also using a chain catcher device (£3 - £30). I will probably begin with fashioning a chain catcher first and seeing how that goes. It's a bit of a shame that Bafang does not function smoothly out of the box, the company should explain this in their advertising or better yet fix their standard rings with a few more millimeters offset. Grrrr.

When I ordered my motor kit, I chose a 46T chainring to be shipped with it, and right now, after my first test, I think it is too hard for both my gear range and local geography. I live in a somewhat hilly area (which is used for UK Tour De France races) so it can be considered not at all flat like the city. I think I would recommend a 36T chainring for my hilly roads, possibly even fewer teeth, but I will test and learn. The 46T is in my eyes even too hard for a cold start on flat (using my rear gear ratio). Ah things we learn!

- Was not true in real testing. It actually works quite well on the road and is nice and powerful with good pull.

So Things left to do are Wire harness making, and cheap chainring solutions. I wonder if PETG will be strong enough for a 104mm BCD adapter? Crazy suicide idea? Or cheap genius?