Feddyflatfoot's homemade trike

[BiGH]

Chased down a Lycra myself this morning

Um..what's a BF?

yeah so did i - scared the crap out of him mighta been since i was going up a hill at 40kph and he was crawling i trued my rear wheel over the weekend - made a BIG difference - wheel speed went up by like 5kph

 

[Mark_A_W]

Actually have no idea about BF. Company in China that sells motors, but no website. Apparently Evehicle here in Oz has been using them for 3 years in their bikes. Same motor that is used in the Sherpa.
Its a geared motor, maybe similar to the Puma?

http://www.evehicle.com.au/New%20Sherpa%20Lithium%20Limited%20Edition.shtml?openmenu=5

I thought they were using a Tongxin?

Their new kit is a Tongxin.

 

[Freddyflatfoot]

Yes, but this isn't the Tongxin motor

 

[Mark_A_W]

Take some close up pics of it please Rob!

I wonder what it would do at 54v???

 

[Freddyflatfoot]

I've got some pics, but with nylon gears, I'm not sure i would want to increase the voltage!
Anyway, I am more than happy with the performance.

 

[Malcolm]

Hi Freddy

I've been thinking about buying a Nano (Tongxin) motor here in the UK, and your photos look identical to it. Any idea what the freewheel rpm of the motor is? I know they make 160, 190 and 260 rpm variants. From the speeds you're reporting it sounds like you must have one of the higher rpm versions. Good to hear you're so impressed with it.

 

[Freddyflatfoot]

Malcolm,
This is not the Tongxin motor! Tongxin motors do not use gears! (they are a geared motor, but use a different type of planetary interface. Balls? Not sure.)
I hear the Tongxins are good, but cannot tolerate overvolting.
This is a BF motor, same as that used on the Powerped Sherpa.
Mark from Melbourne has bought a Tongxin kit. Maybe you could check with him?

 

[Mark_A_W]

No I didn't.

Timbo bought a Tongxin kit.

 

[Malcolm]

Thanks Freddy. It's just that it looks very similar to the Tongxin motor and weighs the same. But then the speed and torque you're getting sound better, so maybe they used the same casing but fitted better internals. You couldn't just take it apart and post some photos for the sake of furthering EV science could you mate?

The Tongxin uses a planetary friction drive, but you reckon this uses a nylon gear drive, is that right? Sounds like a miniature version of the Puma motor. Just when I thought I'd decided on a motor I'm going to have to start looking again

 

[Freddyflatfoot]

Malcolm, check my earlier post. Have a pic of the internals showing the 3 nylon cogs.

 

[Malcolm]

Doh. Sorry, missed that first time.

 

[Freddyflatfoot]

No I didn't.

Timbo bought a Tongxin kit.

Sorry Mark. :?

 

[Freddyflatfoot]

Ok, been busy upgrading the brakes on the trike to V brakes, and then building a tail box, must post some pics,
Anyway, and I know I had a tailwind, but managed to hit 52.8 kph without too much effort! I am impressed!
Downside was that on the way to work, my chain idler spat the dummy. That cause my chain tube to come loose, then the tube let go and fed through the front derailleur, and derailled the chain! Real bummer! Git some work to do now to get the thing sorted. Made it real hard to pedal, so made it to work on motor alone.................................just hope I've got enought juice to get me home!
The next project will be a front fairing, but maybe after summer.............

 

[Freddyflatfoot]

Ok, the trike is going through a major rethink on design.
I made another trike for a mate, and incorporated some new design features to suit him. I also took the BMX forks off my trike and used them on his trike.
I took this opportunity to narrow the track (it was too wide anyway), lower the front boom, move the crossmember back a bit, make my own kingpins to acccomadate stub axles, and add the handle bars from lower down (below seat height), to clean up and open up the cockpit area.
The new crossmember is 'V' shaped to allow easier access to the seat.
I will use 'V' brakes initially, but can go to discs fairly easily with the use of the stub axle design.
The trike has slimmed down by about 8" in width, with the track now at around 29", with a total width of, I think 31 1/2".
It is still a work in progress, and needs some finishing before I can road test her, but I am expecting better handling, maybe a bit lighter with slightly less caster, (by lowering the boom, this was accomplished by mounting the kinpins higher up on the crossmember) and a tighter turning circle. The second trike was 4.2m, as opposed to my original 4.8m.
Must take some more pics and post them!

 

[BiGH]

sounds good! keep up the good work!

 

[Freddyflatfoot]

Just a bit of an update on the trike.
Firstly, the changes I made to the trike front end worked really well, and I reckon it actually handles better with a narrower track. Certainly easier to move around!
I have been getting plenty of use of the trike, using it as a daily commuter.
I have had an issue with spokes, though, having broken 6!
I replaced these, and then broke another one!
The one thing I have been disappointed in, is the extra weight of the SLA batteries. 12 Kg is a lot of weight, for only 36v/10 AHr. Having to lift the rear of the trike to turn it around, was a real pain!
As I want the trike to have useful assist, as well as the being able to ride it around unassisted, I really need less weight.
Fortunately, the hub motor isn't too bad, the total weight being 6Kg, including rim and tyre.
So, I am now rethinking what I want out of the trike, and the assist system, and what my options are.
I could just replace the SLA with LiFePo4 to reduce the weight of the battery, but still considering the options there as well, but
either Yesa, or 'duct tape'.
The other option I am seriously considering, is removing my BB drive, 24v system from my MTB and using that on the trike. Yes, less power and speed, but also a lot less weight! And I will be making more use out of my current 24v LiFePo4 pack.
This is partly because I seem to be preferring the recumbent to the MTB, but that's another story!
This system will only add about 5 - 6 Kg's to the trike, and still give me usable assist.
A side benefit will be being able to go from the (limited) 7 speed cluster, to either an 8 or 9 speed, with a wider gear range.
Remember, I still want to be able to ride the trike without power.
At the moment, I have removed the hub motor and battery pack, and I am really enjoying the lower weight. I have been doing a lot of rides using the trike as originally intended! Yep, not as fast, definitely more exercise, but able to ride long distance without a severe weight penalty.
Don't think I wanna go back to lead!

 

[jateureka]

Nice home build. Would you share the 'plans' or photos for your latest build?

That hub motor you have is a Bafang (BF for short). Plenty of info on here about them. Impressive speed on 36V using a 20" version in a 24" rim though!

With the broken spokes, did the LBS tell you to have them retensioned after 100km? WHat gauge spokes did they use?

 

[Pure]

Check the dates. Last post in this thread was back in 08, last post on the forums was in 09.

Try PMing him and hopefully he'll get an email alert.

 

[Freddyflatfoot]

Ok, it has been a long time since I was on here!
I still have the trike, and the current config is the 350w BF motor, laced into a 20" wheel. The 26' wheel lacked the torque I wanted, but did have the speed!
Can't even remember the last time I rode her? Although I did lend her to my son when he was carless for a bit. He kept flattening the battery, and broke my WattsUp meter, bugger! I think he overused the assist though, as I could get close to 40 k's out of the battery between charges.
Since that trike, I built another, that is now an enclosed velomobile. Still a work in progress.
I have also built about 4 other recumbent bikes, and that pretty much is the direction I have headed in.
I am so much fitter now, that I don't really need the assist. Cycle pretty much everywhere, and ride long distance brevets. So far, in excess of 220 k's.
Having said that, I have setup a bike/trailer combo, that has seen some serious weight on it! Considering putting the BF on the rear for some assist, especially as the front wheel drive loses traction sometimes, and starting on a hill with around 100 kg load can be interesting!
Here's a link to some pics,
http://s281.photobucket.com/albums/kk204/freddyflatfoot/Trike/

 

[Whiplash]

Cool! I would like to build something like this before a long tail! Seems like a simple build for the most part huh? I have a great frame to start with! I just need to get my project bike finished (if I ever get my new motor) and then I can move on to something fun like this!

 

[Pure]

Awesome to have you back Rob. Would love to see more pics of the Velo build.

 

[jateureka]

Thanks for posting the link to the photos.
Looks like you did quite a bit of fine tuning to your original build, you must have learnt quite a bit about what works and what doesn't.