Roger's Trike

     As mentioned, this is Roger's new trike.  The frame is built out of a combination of 1 1/2" box for the crossmember and the boom, 1" x 1/2" box tube for the main frame and cross tube under the seat, and finally 3/4 " round tube for the seat.  The boom is fixed and as Roger is not a "speed freak", the chainring is shifted manually if and when he should need higher or lower gear ranges.  At present, he says 8 speeds are more than enough for him and he might even remove the other two chainrings.  The steering is direct, and the kingpins are inverted with the axle being on top so as to accommodate the front suspension.  The trike weighs 38lbs.

     This view shows the back of the mesh seat which is likely made of catamaran trampoline material.  It is one-piece and has the lacing running through holes and going around aluminum rods inserted into pockets on the edge of the seat mesh.  A much simpler method than using grommets and reinforcing the edge with thick cotton/nylon webbing, which is the way I have been doing it.  I'll be using the rod and pocket method once I run out of the seats I've already made.  You can also see the wide chain pulley that allows the chain to track left and right as the gears are changed on the 11-34, 8 speed cassette.

     This shows a clearer shot of the frame construction.  A nice clean chain line, and the tie rod running cleanly between the seat and the frame.  He has a 160mm 48/38/28 crankset mounted on a threadless BB cartridge, and again, no front derailleur or post.  Both front disc brakes are controlled by a double pull brake lever on the right side, while the rear disc and shifter controls are on the left.  The 451 wheels are custom laced with 20mm hubs on the front, and a standard Formula disc hub on the rear.  The disc brakes are cable, and from personal experience, the disc sets are inexpensive and very effective.  The bar ends mounted on top of the handle bars are for mirrors, speedo, beverage dispenser, etc. :)

     Above are shots of the kingpins and the top-mount axles.  The steering bushings are made of Delrin which have proven to be very strong and durable in past trikes.  The suspension consists of Honda valve springs on the bottom of the king pin bolt.  With suspension of this design, a little bit of toe-out needs to be set when the trike is unloaded, so that when a rider is on it, the suspension settles a little and produces as close to the proper amount of toe in as possible.  Suspension pre-load is controlled by how tightly you compress the springs with the king pin nuts.  Very simple, but also very effective at softening the ride on what looks like a nice stiff frame.  Regardless of the comments and justification for other forms of steering linkages, I love the simplicity of direct steering.

Nice trike Roger :)