Thursday, December 18, 2008


We are collecting tubing, frame, components and ideas for PROTO IV.

The first thing we will do is list our wants i.e.
Aluminum construction (strength vs. weight)
24 in. outside wheel ( rolling resistance vs. strength)
Removable sidecar (ease of assembly/removal)
Permanent mounted racks (reliability and versatility)
Internal mounted outside wheel (Flat step plate/more internal space)
multiple diameter construction (strength and joining appearance)
Front grab handle (ease of entry to sidecar)

Then develop a list of things we would be willing to sacrifice.

1. Load carrying capacity (removable aluminum sidecar)
2. high gears (internal multi speed hub)
3. weight (thick wall tubing)

After that we would brainstorm. (probably add to and take away from both lists)

Once we are convinced we are on the right track we will develop a wire model out of coat hanger wire. This is done by forming the wire with pliers and soldering the joints (measurements are not important at this time we are reaching for the general look)

When we are satisfied with the look or concept (many wires have been removed /moved and or replaced) we will lay out the base of the sidecar in full size (measurements just got critical) on the floor in chalk.

Now to the bender, using the pattern on the floor we shape the outside tubes and fit them together. The cross tubes are next. (we like to tape the tubes together in position)

The base is formed. It is time for the bicycle side top tube so refer to the wire model and go for it. Prop it up in place and fit in the uprights.

Move right on to the outside top tube, this one has the door in it and the outside wheel support.

After it is in place with uprights it will be wheel supports followed by grab handles.

What I have not mentioned at all yet is the donor bike we need to have already removed paint from the locations where welds will be attached.

For PROTO IV integral racks are an important part of the design concept. The outside edges of the racks (both front and rear) will be where the sidecar attaches so rack mount triangulation is extremely important.

Forming the racks will be similar to forming the sidecar but mounting to the bike and having clearance for pedaling and turning can not be overlooked.

With the bike propped in place next to the sidecar also propped in place the last fabrication component is the bike/sidecar connection (in reality this may at the last minute become a permanent mount) We will just have to see how it goes.

Of course after frame fabrication is completed there is still much to do with components, gears, hubs, brakes, handlebars, shifters, rims, spokes, tires, reflectors, cables, cable casings, pedals, toe clips, gooseneck, headset, crank, bottom bracket, seat post and seat. (not to mention paint)

As of yet PROTO IV does not have a name, it seems as though we need to see it in order to project a name onto it.

Very soon now we will have the wire model to show you. (we will post as soon as we have it)

Any feed back is really appreciated. (we do not say we will use it but we want as much input as possible)

1 comment:

JEINKEL-HEIMER sidecar bicycles said...

Turd out it takes a long time, but we have it now.