Bike builders news – Building a velo: Part 7

Feature article by RadicalBrad of

Building a Velomobile – Part 7
Welding the sides outside on a makeshift workbench.
Feature article by RadicalBrad: Already Been Done?
What’s new might actually be old.
Bike builders community chat – hot topics of conversation
Bike builders gallery – new additions:
recumbents, trikes, choppers, cargo bikes & moreBuilders Feedback – we love to hear from you.


Hub flanges and axle adapters for your bike projects
now shipping worldwide 

Free DIY tutorials – now available in PDF format

New AZTV webisode – There and Back Again: A Zombie’s Tale

This and archived newsletters are here.
Thanks for your feedback, and keep those suggestions coming.
See you in the Builders Forum.

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Build a Kids’ Electric Trike – Part 2


The basic triangular frame needs three tubes to hold it together, one at the rear to join the two rear forks, and two more tubes at the front to form a triangle between the fork crown area and the head tube. Shown in this photo is the tube that will join together the two rear forks, creating the frame to whatever width you like. A fishmouth cut is ground out at the ends that mate with the round fork tubing. The tube should be placed about half an inch from the end of the fork leg tube so there is room to make a weld.


With the parts sitting on a flat surface, tack weld the rear frame tube to the two rear forks as shown here so that the fork legs are at 90 degrees to the rear frame tube. Because both forks are sitting on the same flat surface, vertical wheel alignment will be almost perfect, and as long as you get both forks running parallel, horizontal wheel alignment will also be perfect. If the two rear wheels are badly out of alignment, there will be scrubbing on the road, which will decrease battery run time, so try to get the wheels running as true as possible.


Once you have completely welded the rear frame tube, join the two rear forks together so that you can continue the frame layout, adding the two front frame tubes that will form the triangle as shown here. The two front frame tubes will determine the wheelbase (length) of your trike, which should be fairly close to the original bicycle wheelbase so that your pilot can reach the handlebars comfortably. Also shown in this photo is the front head tube which should be set at 90 degrees to the frame tubing, which will result in a final angle of about 65 degrees once all three wheels are installed. The joint between the head tube and the two front frame tubes needs to be ground out (fish-mouthed) to conform to the head tube so that you can make a decent weld along the joint.

Once the head tube has been welded to the frame, insert the forks and three wheels to check your rolling frame. The head tube angle is now close to that of a standard bicycle (between 65 and 68 degrees), so your trike will handle just like a regular bicycle. Now you can finish all the frame welding to secure the main frame triangle to the head tube and rear forks.

Motor and battery

The biggest complaint when it comes to kids and their electric vehicles is how quickly the battery goes dead. On the original stand up scooter, you could barely go around the block once before the battery started to give it up. By using a much larger battery and half the voltage, the new trike will run almost all day on a single charge, and allow the vehicle to get up hills that would normally exceed the smaller battery packs immediate discharge capacity.

Sure, the large battery is quite heavy, but that simply adds stability to the trike, so it won’t tip over as three kids try to stand on it as they roll over the curb. Another very important thing to note when choosing a battery is to ensure you use Gel cell, or non-spillable battery, which is a must for a kid’s vehicle. Unlike a typical lead acid battery, this battery will not leak any dangerous chemicals, even if turned upside down, so don’t use any other type of battery.

The battery will live between the two rear forks as shown here, supported by a few bits of flat bar which have been welded to a battery support base made of angle iron. The battery box base should place the battery at least 4 inches from the ground, so it doesn’t bang on small objects which may roll under the trike as your kids drive it through hostile territory.

The drive motor can practically anywhere on the trike, on any one of the three wheels, but it stays neatly out of sight when positioned under one of the rear forks as shown in this photo. Use whatever means necessary to place the scooter’s drive wheel up against the trike’s wheel so that there is a decent amount of friction between the two wheels.

Inflate the tire to the proper pressure before you do this, and try to keep both the drive wheel and trike wheel inline, so that sideways friction is avoided. There should be enough friction between the two wheels that it takes a bit of force to make them slip, but not so much that they are difficult to turn by hand. The little scooter motor is not very powerful, so a little slipping off the start is better than so much friction that the motor overheats and burns out. A nice smooth tire or at least minimal tread at the point of contact is also a good thing.

Part 3 in tomorrow’s blog

AZ newsletter March 20


** Feature article by Brad Graham – Extending throttle for your electric bike **
Pennsylvania chopper
Spring into bike building
California OverKill chopper
Brazil OverKill chopper
Builders chat
Australia chopper
Wisconsin tall bike
Mini chopper in England

Quad bike in England

“Hi. Here is a pic of my quad for the gallery.

Chris West
Gloucestershire, England”

Home built quadcycle by Chris, England.


Nice quad, Chris. Thanks for sharing.

UK custom bike chopper

“28 gears, front and rear suspension. Perhaps you’d like to show my pics?”

Gerard Walker, Swansea, in the UK.


Great job, Gerrard!


Bike builders rock!

Florida – new Warrior recumbent tadpole trike

“Hi Brad and Kat. Here’s a pic of my new Blue Bullet Warrior.

Thanks again for the great plans. This bike rides just as good as a store brand, actually better because I know who made it.

Keep up the great job you two do.”

Mr. Frugle, AZ forum

Build blog: Mr. Frugle started his build December, 2011.

This is his post in the Builders Forum announcing that he recumbent trike is done:

“Hi guys finally finished my Warrior.

I’ll post a few pics one of the pics is of the speed-o-meter mount I added to the front pulley.

I think someone in the Warrior forum was asking for ideas on where to mount a speedo. It works well, easy to see and not in the way.

I’ve got about 45 hours of labor $375 to $400 dollars invested. The biggest expense was the wheels, tires, and disc brakes ($220 without shipping) and three free old doner bikes two of which I was able to ride.

It’s unreal what people throw out. It was 28F this morning so I thought my shake down run wasn’t going to happen, but in Florida if you don’t like the weather, wait 5 minutes.

Anyway, it warmed up to 70F by lunch so I took it to the local bike trail and put 20 miles on it. WOW! Kool ride. Just a few little adjustments, and I’ll take another ride Monday. Happy peddling.”

That’s an awesome looking Warrior, congrats!

Build your own Warrior recumbent trike

Warrior Racing Trike takes performance and looks to all new heights. With triple disc brakes, under seat steering, and a general racing attitude, the Warrior would easily pass for an expensive production import. Built using inexpensive bicycle components and steel tubing, the Warrior weighs in at only 43 pounds, and has perfect handling and braking characteristics. There is not one single machined part on the entire trike, and everything can be built using only a basic welder, hand drill, and angle grinder!

The Warrior Racing Trike uses commonly available 20mm hubs, so there are no hard to find or overly expensive components needed. The frame is completely made of square steel tubing,and everything else on the Warrior Trike can be found at bicycle shops or hacked from scrap bicycles. The building process is designed to allow anyone with a Do-It-Yourself desire to finish his or her own version of the Warrior Trike without requiring previous bike building experience or specialized tools and skills.

If you have been eyeing up those expensive imported recumbent trikes, but think $4,500 is a bit too steep of a price tag, then get out your tools and build it yourself! For thousands of dollars less than the price of a basic tadpole trike, you can create your very own racing trike that will rival many of the factory built machines available.

Take a look at our Builders Gallery to see other Warrior examples, including many creative modifications to the plan. Our international builders community ranges from students to retired engineers, but they all have one thing in common – the desire to build their own stuff!

Slovakia traveler recumbent trike

“Hello. Here is my traveler recumbent trike from Slovakia.


  • 26″ wheels,
  • rear wheel steering,
  • front of the rider is tilting,
  • front wheel drive,
  • front suspension,
  • suspension seat,
  • delta concept,
  • Rohloff drive
  • and more…
Dušan from Slovakia”
Congratulations, Dušan. That is a great looking recumbent trike.
Atomic Zombie sez, “You rock!”



Built by Mike harder
Saskatoon, Saskatchewan Canada
our own SpinCycle

The TimberWolf Is Born!

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Bottom Bracket in North Pole

“I am looking for a bottom bracket assembly (or a whole bike) for a delta wolf and as the title says, I live in North Pole, AK.”

Read more and join the discussion:    BB in north pole.