Folding Bikes - Home Made "Mini Velo"

Tonight at my local supermarket, I walked outside to unlock my folder after my shopping was done, and this young guy was straddling a small black bike with 20 inch wheels, and was admiring my ride. At first I thought it was a folder, but when I got closer, it was child's bike with a long seat post, and long stem. It also had a rack on the back from a regular sized bike (26" or 700c) so it sat up high above the rear tire like a touring rack should be on a small wheel bike. We exchanged pleasantries but he spoke very little English. I think he was from Mexico or Central/South America.

As I pedaled away, I thought how cool that little bike was. A cheap BMX bike from the local Goodwill, or garage sale, and the possibilities are endless. I've seen how some homebuilders have even converted these small bikes into a short wheel based recumbent, so a compact non folding bike for an adult is even an easier project:)

Regards,
Edward

What, like this ? : o)

http://richard.safier.com/OVR/PT%2011%2008/images/z06_0034.jpg


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Well that is one possibility. The bike pictured looks like it was converted into a fixed gear. I guess the advantage of using a traditional BMX diamond frame is the great amount of stiffness in it, yielding a lot of efficiency. All your power goes into that back wheel!

Edward


What, like this ? : o)

http://richard.safier.com/OVR/PT%2011%2008/images/z06_0034.jpg


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Cannondale made one for a while. Dahon makes them and calls them "flat-pack" bikes. There also used to be a few links kicking around here to Capanese manufacturers who build custom 20" touring bikes.

For several years I am waiting for my children to outgrow the 20 inch wheel mountain bicycle I assembled in first place for my eldest son. The idea is to replace the 406 wheels by 451 wheels, hoping the bottom bracket will raise 22.5 mm from the ground so I can replace the 150 mm cranks by 165 mm or even 170 mm ones. The rest you already know, long seat post, long stem and which me good luck.
Unfortunately for my curiosity and experimentalist spirit, my youngest daughter is still 4 years old !:( What terrible father would take toys from the hands of his own children?!?!

There are many possibilities of buying a used 20 inch MTB or BMX you know. Try looking at the local classified ads in your major, or community newspapers. Also garage sales, thriftshops are other places to look.

Good luck:)

Edward


For several years I am waiting for my children to outgrow the 20 inch wheel mountain bicycle I assembled in first place for my eldest son. The idea is to replace the 406 wheels by 451 wheels, hoping the bottom bracket will raise 22.5 mm from the ground so I can replace the 150 mm cranks by 165 mm or even 170 mm ones. The rest you already know, long seat post, long stem and which me good luck.
Unfortunately for my curiosity and experimentalist spirit, my youngest daughter is still 4 years old !:( What terrible father would take toys from the hands of his own children?!?!

There are many possibilities of buying a used 20 inch MTB or BMX you know. Try looking at the local classified ads in your major, or community newspapers. Also garage sales, thriftshops are other places to look.

Good luck:)

Edward

I've been thinking of taking on such a project. But, the premium would be on finding a light frame. Aren't those BMX frames really heavy b/c they have to absorb the impact of jumps etc?

I've been thinking of taking on such a project. But, the premium would be on finding a light frame. Aren't those BMX frames really heavy b/c they have to absorb the impact of jumps etc?

Some are heavier than others. For example, a "dirt jumper", or a "freestyle" are very robust, and thus heavy to absorb the jumps like you say.

However it's possible to find lighter aluminum frame bikes as well. I had one years ago that weighed about 24-25 lbs. What was neat about that bike is that the seat post was in fact pretty long allowing me to almost fully extend my legs. I'm about 5'9" with a 29" inseam. It was fun, and easy to ride:)

Edward Wong III
Qile Duo 5 Speed 20" Folder

Some are heavier than others. For example, a "dirt jumper", or a "freestyle" are very robust, and thus heavy to absorb the jumps like you say.

However it's possible to find lighter aluminum frame bikes as well. I had one years ago that weighed about 24-25 lbs. What was neat about that bike is that the seat post was in fact pretty long allowing me to almost fully extend my legs. I'm about 5'9" with a 29" inseam. It was fun, and easy to ride:)

Edward Wong III
Qile Duo 5 Speed 20" Folder

Thanks, Ed. I guess these aluminum frames can be found at xmart stores and stuff? Or more specialty stores? Also, when you talk about 25lbs, is that the frame only or the whole built up bike. Thx.

A mini-velo, but not home made, seen at london bicycle show last week.

A mini-velo, but not home made, seen at london bicycle show last week.

Interested in the seat post;Wounder what the diametre is, specs, length?

Thanks, Ed. I guess these aluminum frames can be found at xmart stores and stuff? Or more specialty stores? Also, when you talk about 25lbs, is that the frame only or the whole built up bike. Thx.

That's the whole built up bike. A 25 lb. frame would be beyond heavy! :roflmao2:

I bought that BMX bike at Sears right before they stopped selling bicycles in stores, back in the early 2000's. When I got the bike home, and took it out of the box, I was surprised how relatively light it was for a $129 bike. You had to imagine that for that kind of money, the components were "entry level" but the aluminum frame made up for that quite nicely.

Another pleasant surprise was to find that the stock seat post was in fact alloy, and like the rest of the bike, was painted or anodized in flat black. To top it off, it was long enough for me to ride the bike comfortably.

You could go online, and check retailers or to really save some money, get one used through Craigslist or other source. Are there any thrift shops or pawn shops nearby? That would give you the advantage to inspect it personally. You do want to make sure it's a "racing" type BMX which will be lighter than models intended for stunts, and tricks. Those can be very heavy!

Once you locate a suitable bike for conversion to a mini velo, you'll have to source a different handle post, and handle bar. Like that bike I used to own, the seat post might be long enough, or else you'll have to replace it as well. Perhaps other forum members can give suggestions where to local those parts.

Good luck!

Edward Wong III
Qile Duo 5 Speed 20" Folder

Interested in the seat post;Wounder what the diametre is, specs, length?

The company is Qoroz :-

http://www.qoroz.co.uk/freedomwon/

What you need is a race BMX bike. Originaly all BMX bikes were intended to race,but then freestyle diverged from it ,and stunt bikes emerged. The orginal race bikes were about 24 lb. But with carefull choice of components,"UNI" fibreglass seat/seatpost+11/8 wheels, this could come down to 19lb ish with out costing too much. Childrens race bikes were made that weighted around 6KG,and teams started getting lighter bikes build up with campanlono cranks later. A modern racing BMX will cost a more than this project is worth ,but the weight could be as little as 9KG or less. An 80/90s race BMX bike or frame,might be cheap and ideal if you can find one.

The company is Qoroz :-

http://www.qoroz.co.uk/freedomwon/

Thanks I will look in to it.

ive built a few small bikes with long seat posts and BMX bars.

Lucy is the oldest one I have a picture off. Its a Raleigh BMX that I put another seat tube into. Was an ok bike. It got stolen 3 times. Which I thought strange for it being a rusty old bike.

http://i29.photobucket.com/albums/c296/Alecw35/lucybmx.jpg
I then built a Raleigh Grifter. Its called Super T. Its also got a seat tube inside the seat tube. I'll have to get round to completing the rebuild.
http://i29.photobucket.com/albums/c296/Alecw35/Grifterbridge.jpg

And theres Lil Blue bike. Originaly built from a 15" framed kids MTB. I built it to experiment with twin chain rings on a 3 speed hub. I didnt get a small cog for it. So was a bit slow. Its stripped down now.
http://i29.photobucket.com/albums/c296/Alecw35/lilbluebikelow.jpg

Also got a Puch Mini Sprint. I had an idea of making it into a bike rod. But since its a Schwinn style frame. Anyone that knows bikes tells me to put springers and a banana seat on it. That would make it handle even weirder than it does. Its got a Shimano 3 speed with a 52 to 15 cogs. Its the first bike I nearly threw off the road while riding it. The front came up to the side of the road. Think its needing some work. Will put the SA wheels from Lil Blue bike on it. Can use a smaller cog on them.
http://i29.photobucket.com/albums/c296/Alecw35/82orangebike.jpg
Also built this 3 speed BMX.
I had some garden steel frame work. Cut a bit of it to use as the seat post. Its stuck in the frame now. The pics are from just before I stripped the bike for parts. It had gone really rusty. Think it was the cheap paint I used on it.
http://i29.photobucket.com/albums/c296/Alecw35/BMX.jpg

What you need is a race BMX bike. Originaly all BMX bikes were intended to race,but then freestyle diverged from it ,and stunt bikes emerged. The orginal race bikes were about 24 lb. But with carefull choice of components,"UNI" fibreglass seat/seatpost+11/8 wheels, this could come down to 19lb ish with out costing too much. Childrens race bikes were made that weighted around 6KG,and teams started getting lighter bikes build up with campanlono cranks later. A modern racing BMX will cost a more than this project is worth ,but the weight could be as little as 9KG or less. An 80/90s race BMX bike or frame,might be cheap and ideal if you can find one.

Thanks. What are the tell tale signs that someone is selling a race BMX bike? There's all kinds of bmx bikes that are sold on craigslist in my area and I'm willing to bet most are of the "heavy" kind. But, finding that diamond in the rough would be worth it.

Thanks. What are the tell tale signs that someone is selling a race BMX bike? There's all kinds of bmx bikes that are sold on craigslist in my area and I'm willing to bet most are of the "heavy" kind. But, finding that diamond in the rough would be worth it.

One tell tale sign is the mention of a size of the frame. Different sizing isn't available in BMX bikes of lower quality. Do your research once you find out the brand and model.

I honest doubt this will be a fruitful venture if you're looking for a light weight racing BMX frame though. High end frames are going to be relatively expensive. By the time you're done, you'll probably wind up spending less by converting an Uno or Boardwalk 1.