Project: Home made velomobile design with crank or mid motor

[LI-ghtcycle]

Incredible!

I've often fantasized about building something like you have, but haven't quite gone that extra step!

I admire your dream, and hope to see it come to it's fruition!

It looks amazing, and I love the design of the vertical opening door!

Did you get close to your target weight?

Also, I know you are limited to a 250W motor, how ever, I imagine there are 250W motors that might be rated for that constant, yet can be expected to push out much more for short periods (going up hills, etc.)?

I admire you for staying with a lower power set-up and squeezing as much performance as possible, as the saying goes, "It's more fun to drive a slower vehicle fast, than a fast vehicle slow!" and I too prefer to travel closer to bicycle speeds and be as efficient as possible.

Again, thanks for sharing! Love all the detail in the pictures, do tell us how it goes sorting the suspension!

I definitely would love to have a Velo for the winters here in Oregon, (they are mild at best! Glare Ice being the only hazard) so not as challenging as it must be for you up north, I got as far as selling my car, the next phase needs to be making my Recumbent more Aero with a Zipper or similar windscreen.

 

[Projectitis]

@tahustvedt - Just an amazing build! I can't believe I've only just come across it.

At the start you experimented with aluminium brazing, but didn't touch on it again over the course of the build. I also noticed you bolted your frame I've got some aluminium brazing rods (but have yet to use them) and plan to braze my entire frame with them. Any reason why you didn't end up using them, or any warning against me doing it?

Cheers,
Peter

 

[tahustvedt]

I need more heat than the propane torch can provide to braze large tubes. It works with small parts. The bolted connections are holding up fine.

I blew the controller of the Bafang on monday when I tried to start in a hill in highest gear. Stupid move, but I was able to order a new controller the same evening, so I might be up and running again this week.

I'm working on improving the ventilation now. I added a 120 mm fan in the nose to pull air in through the intake, and it worked wonders. I will add two 3D printed air outlets as well. I'll post some pics when I get it done.

 

[tahustvedt]

Slow TV from my velomobile:
[youtube]9uexy8GHSGM[/youtube]

 

[Wheazel]

Awesome! How much have you been riding your creation so far?

 

[tahustvedt]

Very little. I grew tired of the leaking right shock and steaming windows this winter. I'm adding ventilation now. I would really like some proper oil shocks for the front suspension. The friction shocks on there now are as plush as a block of wood and the right one leaks air. I plan to add a windshield wiper as well.

Today I ordered a Ventisit seat cushion. That will make riding more pleasurable as I get pretty sweaty on my back.

 

[Wheazel]

The sweaty back thing I have experienced alot on my challenge jester.
The stock seat is just aluminum, it transfers heat well, but is hard in the long run. So I am using that grey ~15mm thick material used to sleep on during hikes.
Good comfort pressure wise, but oh so sweaty. The ventiseat should be a good improvement for your seat, I would be happy read about your impressions when you've tried it!

 

[tahustvedt]

Mycontroller broke the other day. I ordered some new transistors and replaced them all with these: https://www.digikey.no/product-search/en?keywords=296-37289-5-nd

Now it's working again. These should last a while.

I've used the velo more in the last week. I fixed the leaky shock with some silicone shock oil and a slight tug at the valve. Seems to hold now.

 

[tahustvedt]

I've added a couple of air outlets behind the cockpit. Hopefully they are enough. They are 60 mm diameter. The hole in the nose is also 60 mm diameter, so there's twice the area out as in, in addition to the other holes in the structure.
View attachment 2
View attachment 1

 

[Wheazel]

You dont have any easy way to test power consumption at 50km/h right?
I think this would be very intresting to compare with other bike models.

In my experience ~50km/h is where aerodynamic differences really starts to show.
Several hundred watts difference in consumption between my different bikes at this speed.

My challenge jester probably is the most efficient, but its not electrified. If I were to guess, maybe 700W would be enough for 50km/h.
My retired hybrid road bike rc build wanted approx 1kW for 50km/h.
The also retired upright tilting trike need about 1300W (winter tyres), and the cargobike somewhere in that area too.

How does the vents you installed work at different speeds? Big difference?

 

[tahustvedt]

I can't pedal it that fast. It's not even geared for 50 km/h. I can do 40, but it's hard. Harder than my road bike.

I have a Powertap 26" rear wheel on my MTB, but haven't done any tests. I would have if the velo was faster, but now it's just a pig so I haven't bothered. I'd have to change the tire on it to be accurate.

The rear vents didn't seem to do much on my ride yesterday. Maybe they are located in a high pressure area.

 

[Projectitis]

How are you powering your auxiliaries, like your fan? Have you got a DC-DC converter coming off the main battery, or a separate powerpack?
And was there a reason you sawed right through a triangle brace to put in your outlets

 

[tahustvedt]

I use DC-DC regulators. The vents need to be where they can extract air from the cockpit ceiling, so they needed to be in that area. They are made with a brim that provides stiffness around the hole, and the brace.

 

[tahustvedt]

I tried turning up the speed limit to 50 m/h yesterday. The motor spun out at 44 km/h, but I'm sure it would have no problem reaching 50 if I had a bigger chainwheel. The motor has a bout 1000 W when braked down to 60 rpm, but this was about 80 rpm, so the power is a lot lower.

It was very fun.

 

[Projectitis]

That sounds like a blast!

I have a 750W middrive bafang BBS02 on my upright commuting bike. It can hit 50km/h even with the trailer But I guess the velo is a bit heavier! I think I have a 42 tooth chainring, and I have a Nexus 8 rear hub.

 

[RageNR]

Slow TV from my velomobile

Now THAT... IS COOL! Nice job.

 

[tahustvedt]

That sounds like a blast!

I have a 750W middrive bafang BBS02 on my upright commuting bike. It can hit 50km/h even with the trailer But I guess the velo is a bit heavier! I think I have a 42 tooth chainring, and I have a Nexus 8 rear hub.

When it stops accelerating it seems lightly loaded. It only stops accelerating because the motor reaches the rpm limit. I can't be bothered to make a bigger chainwheel to test higher speeds for it though. The current size is the most practical for my use.

 

[tahustvedt]

She's being painted now. Just need one more coat.

 

[tahustvedt]

Finished. The finidh up close isn't great. I used a roller, and the masking isn't perfect.

 

[robjos1]

Great work there! It will really stand out with the red when it's outside. The whole project is very impressive, can't help wondering how it would go with a 2kw+ motor however

 

[Wheazel]

I think that is a great choice of color in terms of visibility.
My experience with the red cargobike is that cars see me much more reliably compared to my gray/black roadbike.
The bigger signature also helps ofcourse, and will help even more with your velo.

 

[amberwolf]

It's part of why I went with red on CrazyBike2 and SB Cruiser (also because much of what I built SBC with was already red retail signage/fixtures/etc). I'd've gone with DayGlo Pink but it fades to non-glo light-pink/white in months here, even if you don't leave it out in the sun, and costs way too much to keep redoing it.

 

[tahustvedt]

I am going to replace the front shocks. I received one SR Suntour-shock to test, and it's way better than the old friction shock. I had hoped the friction shocks would loosen up, but they are still as firm as new.

 

[tahustvedt]

Playing with the idea of installing solar panels on top. The efficiency will be low where I live, but lets ignore that for now. How would I safely interface the solar panel to the battery so that it adds energy whenever the sun is shining on the panels?

 

[amberwolf]

There's a lot of different options in the Solar charging a bicycle thread, and some info in Parajared's solar trike thread, among others.