Rick Wianecki's leaning trike
Rick Wianecki's Leaning Trike Project
These web pages chronicle the design, construction and evolution of Rick Wianecki's leaning trike. The design of this trike allows it to be ridden like a normal bicycle, and in fact, while moving, it feels and leans through corners just like a normal bicycle. A locking mechanism is used to lock the bike into an upright position when stopped. This type of vehicle would be ideal for faired commuter Velomobile. Rick's trike uses some of the concepts brought to light by Wayne Soohoo's leaning trike, though Rick has re-thought and simplified the lean and lock mechanisms.
Trike Design Trike Construction Hub Centered Wheels  
Trike Construction

These are the top and bottom arms. The arms connect to the main frame and rotate in nylon bushings on stainless steel on pivots. The bottom arm has threaded inserts to accept rubber bump stops that are used to limit the lean. 
These are the left and right uprights. The uprights are the main attachment point for the wheels and brakes, and steering components. The uprights are connected to the top and bottom arms with modified rod ends to allow leaning and turning. 

Note: the reinforced bent tubes for the cantilever brake mounts.

The rear suspension swing arm is fabricated from 1.5 inch oval tubing with vertical dropouts.
These are the parts that make up the leaning and rear swing arm pivots. Nylon bushings pivot on stainless steel tubes. There are bronze thrust washers placed on each end to take any longitudinal force.
The main frame being painted. Note all the attachment points for the front arms, rear swing arm and steering stem. Bottom bracket is fixed and adjustments are made with a sliding seat. The vehicle was designed to fit Rick. So the adjustments in the seat are to fine-tune the setup.
To begin assembly after painting, the bottom arm is mounted to the frame. Then the left and right uprights are attached. The top arm is added. In this picture one can better see where the handle bar stem will attach to the frame. 
Close up shot of the flip-it stem mounted (before painting). The stem is a modified Flex stem that was purchased for $5.00 closeout at Bike Nashbar. Standard headset bearings are used with a modified 1 inch threaded steerer tube.
This is a homemade tube bender. I have dies for and inch tubing. Picture shows bending the inch .035 DOM steel tubing used to build the seat and the u-shaped rear seat support.
To control or stop the lean a mechanical disk brake is mounted to the main frame and connected to the left brake lever. A stainless steel bar is mounted to the lower arm and slides between the brake pads. To hold the trike upright one justs applies some pressure to the left brake liver and the disk brake grabs and holds the trike in that position. This is only used at stops and in very low speed situations to assist balancing.

You can click on this image for a larger view.

This is the front brake balancer setup on the vehicle. The right brake lever works both front brakes. So that both brakes are applied equally a balancer bar arrangement is used to equalize the cable force.

You can click on this image for a larger view.

Partially assembled and doing the final fit up of the seat.

You can click on this image for a larger view.

Side view of the trike showing the rack that has been integrated into the seat.
Rear view showing the gear step-up and rear suspension.
Front view with the trike leaned over.

Now that I have had some time to live with and ride the trike it is time for some upgrades and modifications. One of the design compromises that was made was with the steering geometry. On fixed trikes the kingpin is angled so the centerline of the pivot intersects with the contact patch of the wheel. On this trike this only works for one angle of lean. 
I have been working on building a pair of hub-centered wheels. These wheels will have a deep carbon dish attached to 305 aluminum rims. The dish will be attached to custom machined aluminum hubs that will allow for the use of front disk brakes.
Here's a picture of the brake handle activated tilt lock on Rick's trike, after Rick modified it to increased the lever arm. This makes the brake hold the bike upright better.

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