How to create a smoothie making human powered bike blender for less than $25

FeaturedContest WinnerContest Winner
Picture of How to create a smoothie making human powered bike blender for less than $25
I love biking. I also love smoothies. That's why I was really excited when I read about the B3 mini from rock the bike in Make 11. However, upon visiting their site I was dismayed at the cost of the blender, about $250. Thus, not knowing if it would work, or if it was even legal (patent infringement and such) I set of to create my own bike blender.
This instructable documents how to create your own inexpensive, energy conserving, bike powered blender. Since appliances account for over 20% of your electric bill, this is one less energy consuming machine in your house. And making a fruit smoothie is twice as good for you as before; both in nutritional value, and also in the exercise you get. It isn't an incredibly difficult build, and even the most inexperienced Maker should be able to complete it in less than 3 hours (not counting glue drying time).

Step 1: Necessary Materials

Picture of Necessary Materials
Materials needed:

Blender: Theoretically, any blender would do. I'm using a Hamilton Beach personal blender that was practically made for this project. The two key things needed are that:

1) The blender jar locks in place
2) There is a transmission disk, instead of the motor connecting directly to the blades

A M4-.70, 19cm long bolt: In a perfect world, a bolt of this size would exist, but the longest I could find was a 7 cm. If you can find one, great, otherwise you need: 3- 7 cm, M4-.70 bolts and 2 coupling nuts of the same size.

Old bicycle inner tube

1x8 board

3x4 metal plate

2- 1.5 in. diameter wooden wheels

4- 2 inch bolts of any size, and 4 matching nuts

2- 1 inch wood screws

2- M4-.70 Tee nuts

Bicycle rear rack: any rack should do.
1-40 of 86Next »
diegor310 months ago

Es muy Interesante, el proyecto por ustedes implementado, felicitaciones, si fuera posible de la información, me fuese enviada a mi correo, en traducción al español

Cordial Saludo



Diego M Restrepo M

alcurb1 year ago

Great solution. Pedal Power!!

DIYDavid2 years ago
Do you have any suggestions as to how to keep the wheels from moving as they spin around?

This tutorial has been really really helpful in my bicycle-blending attempts. I'm using a stationary bike, and constructed a simple base stand from PVC pipes for about $15. I'm having troubles both getting the wheels to move the shaft, and, if they are moving, to not move up the shaft, away from the moving wheel on the bike.

kmt2 years ago
Thanks -- we constructed this bike blender and it worked great. We have some questions/comments/feedback.
1) We used tee nuts on the wooden wheels as you suggested, and a single long threaded rod, but how did you keep the wheel assembly from 'climbing' up the threaded rod (which is bad) rather than turning the rod (which is what is desired). Our solution was to place a lock nut on the threaded rod above wheel assembly and that worked well.
2) What is the purpose of the metal plate? We skipped it without any obvious problems.
3) our long threaded rod tended to 'climb' upward as it rotated (the hole we drilled thru the wood was just a bit larger than the threaded rod, so it would naturally climb as the threads rotated) and this tended to push the blender jar out of its cradle as we pedaled. (I guess your assembly didn't have this problem?) Our solution was to have somebody physically push down on the blender jar at all times, but eventually the jar was ejected from the blender and broke :( any ideas for us?
I_bike (author)  kmt2 years ago
1) I used two wheels, each with a tee nut in it. If you counter turn them so that they tighten and press together, they should stay in place and not climb the rod.

2.) I used the metal plate to attach the blender to the bike. It wasn't the best method, but it's all I had on hand at the time.

3.) It's been a long time since I made this/used it, but I don't think I had this problem. I'd suggest counter turning two nuts below the board, and placing a washer above them. This should keep the rod from climbing up.

Good Luck! Let me know if you have any more questions:)
Hi there, I'm having trouble getting the motor out. Attached is a picture of the inside of the blender. Advice?
I've tried unsuccessfully to hold the white disk while using pliers to twist the motor off. It seems like I'm missing a step...
I_bike (author)  bike it, like it2 years ago
Gosh, it's been a while since I did this. If this is the same blender (and they haven't made any major revisions), I think you have to grab the white disk, and unscrew the motor rotor (not the housing). Let me know if that doesn't work. It may be reverse threaded, I can't remember.
i was going to say you could use all thread.
ccofer14 years ago
Be nice... Ice is the way to go. But you've gotta carry the ice in cooler. Use an Instep double trailer. These can carry 100 pounds. Ice, cooler, ingredients. cups, straws, alcohol, uh, hand santizer in backpack. okay. Im psyched!!!!
intercreate4 years ago
Hi - I am organising an eco-creative event for a non-profit org and would like to be able to use the above image to promote a workshop for making bike blenders.

Is there any chance I could get the main/top image of this page a little larger for print? Or find another similar simple but colourful one at a high resolution and creative commons copyright or other?

Thanks alot --
Mig Welder5 years ago
Couldn't threaded rod just be used instead?
I wish I had the resources on making one of those. I quite fascinated on the different ideas people are coming up with in generating energy. The most popular I've seen is about stationary bikes. This article summarizes them http://www.dogengine.com/us/used-stationary-bikes.php (scroll at the very bottom of the page) and I just can't wait to implement those ideas myself! But I still need time to recovery from my surgery :(
I_bike (author)  Mig Welder5 years ago
Threaded rod would be ideal, but as I stated in the instructable, I couldn't find any thread 7 mm rod. None of the local hardware store's carried it, but they did carry shorter bolts, which I could combine together to make it: "A M4-.70, 19cm long bolt: In a perfect world, a bolt of this size would exist, but the longest I could find was a 7 cm. If you can find one, great, otherwise you need: 3- 7 cm, M4-.70 bolts and 2 coupling nuts of the same size."
jet_ski7 years ago
Good work! I was planning on something like this myself but you beat me to it. I have been having a problem sourcing a cheap blender - the cheapest I've found has been $40 (I'm in Aus), how do you tell in the shop if the blender is the right type?
See my comment above, just make it work by using metal epoxy if the parts aren't a perfect match. Beware, this is for low-torque load applications...you are on your own if you use it for other things!
I_bike (author)  jet_ski7 years ago
Really any blender will work, some just work better than others. Try to find one that has the jar locked into the base, as that is necessary to stop the smoothie from spilling. Also, the project is much easier if you use a blender with a transmission wheel instead of a post connecting directly to the blades. I used a blender I bought online from target, which I think you can do in Australia: Hamilton Blender. Otherwise, just try to find a cheap one that fits the specifications.
Tarps7 years ago
Great instructable - I have had complications, though:

On the first blender I took apart (Oster brand), The rod has some odd tread pattern that's neither metric nor standard. I went to 3 different hardware stores and asked for help, but no coupler nut or any other nut screws onto the rod right. I was able to partially screww one coupler nut on but since the threads don't match, it doesn't go on straight, so the wheel I attached spins obliquely.

The second blender, an older Hamilton Beach, has a rod that is smooth, not threaded, so I don't know how to extend it.

I got both of these blenders for free, so no big loss. I'm using a skateboard wheel instead of wooden wheels.
lsmith254 Tarps5 years ago
Two words I love lately..."metal epoxy", small tubes available...put it exactly where you want it, wipe away any "strings" while it is still wet and soft like toothpaste, as when it hardens, you will have to file away any unwanted drips. I have successfully repaired welded outdoor furniture, antique stained glass lamps, attached threaded rods to un-threaded ones, and repaired thrift-store silver pieces that were broken...enough to get more "decorative" life out of. Just glue the head of the bolt to the bottom of the shaft. Presto...it glues metal to other things, too; I learned about it from someone who repaired a crack in an engine block of a VW and then drove it to CA without any problems. (User beware!)
I'd also thought about the rotting ingredients. What about a pannier conversion, lined with coat insulation (from a good fabric source) all around the inside, and insert the frozen packs into made-to-fit pockets, thus creating an "ice box' on wheels, to go with the blender?? There's got to be an old pannier set sitting about just waiting to chill some berries and stuff. Drawback is, all the ice is heavy.
I_bike (author)  MacgyverGrrl7 years ago
I did the opposite and turned a cooler into a pannier. The main issue is not so much the weight (ice is heavy), but that the ice can't keep it cold enough for long enough. The fruit will keep under semi-cool temperatures, but the yogurt needs to be kept under 40 degrees Fahrenheit. During experiment, on an 80 degree day, the cooler was only 52 degrees, not even close to the required 40 degrees. If you have any good suggestions, please comment.
dry ice...
hi, great plans here =)
One thing you could try that i have seen work at a festival cafe is making a box out of kingspan-this is an insulator for walls and has foam on one side and a reflective surface on the other. it is expensive but can bbe found in skips from building sites.
Make this into a box silver side out and it will keep your cool things cool

wasnotrice6 years ago
how do you do that
Refunk6 years ago
Uh, as for blending with ice, any blender works a whole lot better if you *first* add liquid (say a cup or so) and *then* add any frozen content, like maybe a cup or two of frozen/other content, blending immediately before the bulk of the mass has time to really freeze together. And never more than about 2/3, 3/4 full. With this drive system, somewhat less.

The skateboard wheel mod someone mentioned is excellent in terms of protecting the tire sidewall. Modularity to enable riding & rack use without blending would be ideal. For stationary operation, installation of a large, *stable*, bracket-style (fold-down "C" shape) kickstand which raises the rear wheel off the ground but still allows pedaling should work.

Altogether a very cool instructable!
Mr.S6 years ago
I'm hoping to do something like this with some students, but have 2 questions. -does anyone know if it's possible to do it with a stationary bike? -would it require less power if we used a smaller blender?
If you put it on one of the bicycle stands meant for stationary cycling, then yes (I believe it's called a bike trainer) As for the power, most likely no. It's directly proportionate to what you physically exert upon it.
Hi to your no 3 future addition u could use a old small box and add a peltier unit and a Fan to make a Cooler
Justin Lam6 years ago
i bought the same blender that you used, but i'm having trouble taking out the motor inside the blender. any suggestions?
I_bike (author)  Justin Lam6 years ago
If I remember correctly (and I probably don't) the motor is mostly held in by the screw on wheel that connects to the blender jar. To get the wheel off you need to grip the wheel in one hand, and the motor rotor in the other with a pliers, then unscrew. If that doesn't work, I'm sorry. I really don't remeber how I got it out. See if you can post some picks of the insides, that might help my memory.
king_zilla6 years ago
is there a video anywhere where i can see this blender/bike in action?
I_bike (author)  king_zilla6 years ago
Sorry, I don't have any video of mine in action, and I can't film any until it warms up here in icy Minnesota.
There are a few decent videos of bike blending action on YouTube (although none of them are mine). Also, there are some videos of the B3 (my inspiration) on the rock the bike website. I'll post some footage as soon as the snow thaws.
oh! alrighty! I'll check 'em out... ok! can't wait for 'em!
snotty6 years ago
Nice work! Your use of 2 t-nuts on wheels is genius. In the model pictured here I used a hub and axle with the bearings removed and tightened to lock it together. The spoke flange touches the tire to get power but this thin metal causes tire wear and is not ideal. And there are no bearings in this system. It's rather ghetto compared to yours.

I have two suggestions:
1: The most recent blender bike I made uses a food processor. I chose this because it is less likely to jam thanks to it's smooth, round cylindrical interior surface. Also the blades are longer so they chop faster at the same RPM. These two factors make a big difference in effectiveness. Plus food processors lock down to their base. And some food processors end up in the garbage due to a broken/slippy drive belt despite being in otherwise good shape. On a bike you run the blades directly with no belt so anything with a broken belt or motor will work.

2: Try dry ice for your cooler. It should stay cool all day, maybe all week! Howstuffworks tells me dry ice sublimates directly into gas so your cooler will stay dry except for condensation. Dry ice is readily available so you might be able to get it for free if you ask the right person the right way (think ice cream vendors). You might want to wrap it in a towel or something; at -78C (-109.3F) it could freezeburn your bananas yo.

Here is some food for thought. Police: Ice cream vendor used dry ice to burn kids http://www.canofun.com/cof/forums/thread-view.asp?tid=12325&mid=76745 I bet that guy would be a good source of dry ice.
bike blender medium low.JPGbike blender detail tire interface.JPG
I_bike (author)  snotty6 years ago
Nice work on your blender! i especially like the mounting bracket, it looks alot easier to mount than my aluminium plate. I would seriously recommend switching to a softer friction wheel. Not only will a rubber wheel be better for your tire, the coefficient of friction between the two wheels is greater leading to a more efficient transmission of power. Thanks for the tips. Recently I seem to have solved the problem of keeping the ingredients cool. I'm using a dynamo powered peltier circuit inside of a cooler. I'll try to get an instructable up soon, but it may take a while.
evank6 years ago
Easy! Build or get a bike trailer, and put a small hole or spigot at the bottom to let the water out. A little dripping never hurt anybody. We built a trailer for a class project, and it was less than $60. Our Trailer Since it attaches at the wheel, and not the seat post, it won't interfere with the blender, and it holds way more than panniers do.
Macpaulster6 years ago
Nice work! This is very much like the B3 you mentioned, as offered by rockthebike.com/blenders. This unit is now called the Fender Blender Universale. To view a video showing the three Fender Blender options offered by Rock the Bike, and the advantages of each, go here:

JellyWoo7 years ago
is it easy to remove this contraption from one bike and put it on a different bike?
1-40 of 86Next »