Building the CNCCookbook Fat Tire E-Bike Conversion, Part 1

4 months by cncdivi

I’ve been wanting to get more exercise, and bicycle riding is ideal. Living in beautiful Northern California, where the weather is great most of the year and the scenery is fantastic, it’s a perfect fit.

However, my house is on top of a very steep hill, making it difficult to get the bike up.

I quickly realized that an e-bike would solve this problem. After researching and looking at various options, I decided on a solution.

In this series of articles, I will guide you through converting a conventional bike into an e-bike. We will also explore using CNC and other techniques to create accessories for the bike. We’re going to Hot Rod this bike!

The Donor Bike

I was sure I wanted to convert a used bike.  The question was what kind?  There are so many different kinds of bikes!

I started out thinking a full suspension mountain bike would be ideal, but ran into a few problems.  They’re complex bikes, so fairly expensive.  And so many choices.  I was also reading varying opinions about the idea that you want a really sturdy bike for a conversion.  Several of the more prominent e-bike YouTubers were leaning towards steel framed and somewhat heavier bikes.  Turns out I like the look of those bikes too.

So I decided on a Fat Tire Cruiser.  It didn’t take long watching Facebook and Craigslist to find my bike:

The bike is a Mongoose Dolomite with a few updates (always a nice bonus from a used bike).  It’s in great (better than new with the updates) condition and ready to rock.  The updates are new grips, bell, thumb shifter, new saddle, and cargo rack.  There may be more, but I haven’t gone over it with a fine toothed comb.

FWIW, you can buy one new on Amazon for circa $500’ish.  Choice of color seems to move the needle from a low of $449 to a high of $685.  Used, these bikes are available for up to hundreds less.

This is a low end bike, made in China.  It has a steel frame and it is pretty darned heavy.  That’s okay for my purposes.  I want a bike that is solidly built, can take the power of a good-sized e-conversion, and that is basically fun.  I am not going to compete or anything like that.  I am going to take it easy, and cruise down off my hill to go get afternoon coffee, a snack, or just to visit the beach for a scenic ride.

Despite the fact that these bikes are low end, their owners for the most part seem to love them.  I can’t blame ’em, I think the bike looks like a lot of fun right from the get go.  But, I did mention projects ahead to update it, so I want to leave you with a glimpse of what’s possible.

How about this Italian-made version from Italmoto:

Note the wooden faux gas tank battery box.  Isn’t that a kick?  Perfect CNC Router project to make tanks like that.  Might be fun to make a matching wooden headlight too.

Put some saddle backs on it and it just gets better:

The Italmoto has a suspension fork as well, and my bike doesn’t.  We will have to see about fixing that.  That’s the great thing about Hot Rodding is your donor vehicle is just your canvas.  You can paint whatever you choose on it.

I bet you’re wondering, as I did, whether my low end Mongoose could ever keep up with the sleek Italmoto?

With Hot Rodding, nearly anything is possible.  But the bar is in reach here.

The Italmoto uses a 250W or optional 500W hub drive electric motor made by Bafang.  Motors made by the same people are readily available for conversions all over the net.  In fact, we will be using a much more powerful 1000W unit.  Sweet!

What about costs?

The Italmoto is a cool $3000 machine.  Our bike will probably be more like $1500 in its initial electric configuration, and then we’ll see where the accessories take us.  I doubt we will make it all the way to $3000, but we are going to have a lot of fun along the way.

So, stay tuned for future installments. There’s a sign-up form for our newsletter below to make sure you don’t miss any of the installments.

I’m not going to boil the ocean on this project, meaning, I am going to get it running in electric mode first, then I will go from there.  After each installment, I want to be able to ride the bike again so it’s never torn down for an excessive length of time.