Introduction: How to Make the Bus Bike, a 9 Person, 6 Wheeled Bicycle.

 A few years ago i decided biking with my friends would be more fun than biking alone, and what better way to bike with friends than for everyone to be on the same bicycle! 

Thus the Bus Bike was born.

I used nine bicycles, cutting and welding them into three single-speed triple bikes, then welding bars accross them, and finally connecting the three handle bars in an english steering setup. 

It was pretty straight forward and turned and rode surprisingly well. With nine riders it was akin to a train. Very fast, very powerful and very difficult to stop. 

i hand built six wheels for it, using double gauge spokes, rims, and hubs, and put single speed bmx freewheels on the back.
I ended up taking this to burning man and all of the wheels eventually taco'd.
Foreseeing this possibility i brought innumerable extras and thanks to the rugedness and universality of the design was able to throw random wheels on where ever they were needed. I did find however that single speed coaster brakes should not be attached because of the riders desire to back-pedal constantly. 

I used a standard 110 mig for this project, be careful to grind away all paint when making the connections. 
Materials included, bikes (9+ extras for donor parts), around 40' 1.5" steel tubing, lots of wire feed, lots of grinding disks, saws-all blades, paint.  

I found a saws-all really came in handy for chopping up the bikes and rounding out the connection points, pre-weld.

Step 1: Get Your Materials

 your going to need a lot of bikes.
not just the obvious nine, but a least half again more for scavenging parts.

i used all new chains, and built all new wheels, but you definitely don't need to do that. The wheels ended up breaking anyway, and the chains were just so that they were all the same kind and saved time.

your going to need a bunch of steel tubing.

your going to need a lot of disposables, ie: grinding wheels, saws-all blades, and wire feed.

thats really about it.

Step 2: Cut Up Some Bikes and Weld Them Togeather

 So I wasn't building a beautiful bike. i didn't make a jig. i didn't even have a standard for for them.
My strategy with the cut and weld was, make the three triple bikes. anyway possible.

I tried to keep them straight, as best i could for the chain line, and i tried to keep them about the same length.

As far as design goes, you have to start thinking about your drive trains. Basically I used crappy mountain bikes so most of them used multi-speed width chain, which worked out quite nicely. The way the chain worked was it went, big chainring to big chain ring, little chain ring to little chainring. so the gear ratios were not perfect , but it ended up working out basically the same for everyone. 

Anyway the only reason you need to think about this now is that when you weld the bikes together make sure you have similarly sized chainrings paired together on the triple bikes.

Basicaly i cut off the rear triangle of the front bike, the front column and the rear triangle of the second bike, and the front column of the third bike. they ended up sort of sloping down in the back so that the last set of pedals came a lot closer to the ground then the front, but whatever, they cleared.

Also i used some pieces of the steel tubing to support the connections as you can see in the photos.

the handle bars were removed from the back two and welded where ever they fit.

Step 3: Drive Train

 unfortunately i don't have a picture of this, but like i said:
big chain ring to big chain ring,
little to little,
and big to free wheel.

also weld on rear derailleurs as chain tensioners in between the chain rings. these have to be welded in such a way that the spring is very tight, as three people pulling sometimes in different directions puts a lot of strain on the tension system. a more traditional tandem setup if you know what that looks like may be easier. i just had the derailleurs and a welder and was on a roll.

Step 4: Steering

some of you may be wondering how a beast with 6 wheels can turn. well it turns very well actually using a system called Ackermann steering. ( i always thought it was called english steering)
Learn all about it!: 
en.wikipedia.org/wiki/Ackermann_steering_geometry

basically you have to draw a line from the pivot point of whatever wheels you want to turn to the center of the rear axle. (or in this case the rear center wheel)
On these lines i extended a piece of pipe about a foot out from the handle bar stem, then attached a bar across all three of the front wheels. i suppose it would work for any number of wheels.

anyway, it works which is nice. 

Step 5: Gather Peeps and Ride It

it was never very hard to find people to ride, storage was another thing though...