Long wheel base front box cargo bike


1 kW
Apr 26, 2008
Western Australia
I'm keen to be able to carry two kids plus gear up in front of me with an ebike and I want to build the frame myself. I have also been keen to try out my new tube notcher and my tig on steel.
So after looking around the net for frame ideas, I spotted CETMA Cargo bikes, http://cetmacargo.com/CETMACargoHello.htm.
I like the style, size, steel frame and the fact I can use a ladies mountain bike for the rear section.
I only want around 30 to 35km max with plenty of torque so this one will be powered by a rear 12 turn Mac and LiFePo4 from Cellman.
I did a really basic sketch from pictures on the CETMA site.


I went to the local tip and bought two donor bikes, one ladies mountain bike for the rear end and one for the extra chain stays.
These photos show the extra chain stays welded in.


I also doubled the rear dropouts up, this bike is going to be heavy and have precious cargo.


These next photos show the 50mm bottom tube and 38mm head tube welded in.


I had a visit at Aussie Jester's today and I borrowed his tube roller, it did a sweet job on the 50mm main bottom tube.


More to come soon.
:shock: Surprised there hasnt been more comments on this Matt! this is
one practical bike for anything from, daily errands to the shops and/or lazy sunday
rides carrying the kids up front...as always its already looking very professional
you attention to detail is always evident.. keep up the good work shall be watching
enthusiastically for updates! best of luck buddy :)

Damn, this is almost exactly what I want to do with my cargobike im building. Will have to mix some ideas around when I get my paycheck and start building.
I'd like a cargo bike too.
A friend in white gum valley has a Bakfeits, and the owner of the painted fish in freo has one similar. Beautiful but really expensive.

I'm sure yours will be great.
How's the build coming along? Envious...
Thanks for all the positive feed back guys, much appreciated.
Cargo_Tom said:
Have you settled on the specifics of the cargo area build yet?
I've got 850mm on the sketch for the length, but I think I will make it 900mm x 600mm as this is half a standard sheet of ply wood.
The cargo area will be very similar to the CETMA bike with a box like this http://cetmacargo.com/sa26.jpg
Thanks for the links Cargo_Tom, some excellent bikes there.
Gregory said:
And Metrofiets have some very good looking cargo bikes too
Thanks Gregory these are the ones that first got me interested.
nechaus said:
Have you been tig welding for long?
your welding looks A+++
Thank you, however I've seen a lot better welds by other people. I have been MIG welding on and off since school metal work classes, about 25 years.
As far as TIG welding goes, I did some on the job training about 15 years ago for about 7 months and then started up again recently when I bought my own AC/DC TIG machine.
Samd said:
How's the build coming along? Envious...
I'm waiting for the sand blaster shop to clean the back end up and then there will be more fab work.
Cheers all.
In the last week I have made some good progress with the frame fabrication, it is basically finished apart from the steering and the stand.
The frame feels very strong and not too heavy.
Here are the latest photos.







Looks great Matt! Very neat bends and welding :mrgreen:

Cromo tubing? Looks strong, good trianglation.

I'm looking forward to seeing this on a group ride when the weather warms up :wink:

Paul :D
I was skeptical at first from the sketches, but after this recent pic I can safely say you do very good work...and its a good design, worthy of copying. I would not hesitate to pay you to make a bike frame for me.
Thanks for the kind words guys.
spinningmagnets said:
I was skeptical at first from the sketches
I probably would have been as well, that was a really simple sketch just to show the layout. I mainly worked by measuring the many photos of the CETMA bikes that are posted on flickr.
I purchased a sheet of 12mm marine ply and cut the deck sheet out.


I had to modify the front forks, these are BMX forks that had huge 14mm axle slots and I need 9mm for my axle.
I filled the slots then re cut them and added some retaining blocks for extra safety.


I also had to make and attach disc brake caliper mounts on the front and rear.


In this photo you can also see some panel beating on the rear stays that allows a 203mm disc to fit.


Note the black 12 turn Mac from the awesome vendor CellMan.


More to come soon.
Since the last update I have made the double kickstand, rear rack and front box.
I did a rough install of the electrics and did some test rides and everything seems to work, powder coating is next and the final stain and oil of the box is needed.
The bike rides great and the kids loved it.






Hi, me planning to build one as well. What was the head tube angle you went for? What is overall length of the bike? So far i came out at 2.6meters and thought it might be too long?
agniusm said:
Hi, me planning to build one as well. What was the head tube angle you went for? What is overall length of the bike? So far i came out at 2.6meters and thought it might be too long?
This bike is 2.7m long and the head tube angle is 22deg from vertical.
Awesome cargo bike!
Reminds me of this one - very functional!
MattyCiii said:
Reminds me of this one - very functional!
http://fixedgeargallery.com/contest/gro ... dMahan.htm
Nice work there!
AussieJester said:
What colour powdercoat you going with ?
Hey Kim, I'm going for a white frame, black wheels etc and dark stained box, like this one, http://cetmacargo.com/sa5.5.jpg
Hey Matt,

Neat job, it looks super cool.

i am very jealous.

I think you have started something and there will be a lot more of these springing up in Perth over the coming years...

I've been pondering one, too, for some time. Mine will not likley be as neat as yours. :lol: But any technical info you can stick in a single summary post (perhaps editing it into the first post) about the frame's measurements, angles, materials, etc., would be helpful to all of us that want to copy your successful design.... :) (says the man that has yet to do any of this for any of his own builds.... :oops: )

That is, after you have successfully tested it with an overload of cargo in the box there. ;)