Nairobi, week six (july 12 to 16):

after ordering the engine from the states last friday, we are resigned to waiting for it to arrive, with even greater desire that it arrives within the allotted 7-10 business days ...

the first half of the week was spent finishing up the mechanical hardware for the first prototype, namely working out mounting and alignment of mountain bike brakes, wheel choice/replacement and brake cable wiring ... the switch to a mountain bike wheel has been fairly fruitful in terms of brake mounting ease and performance; though more testing is needed, the brakes seem to be doing the job they were designed to do; hopefully the switch to the heavier duty wheel will provide additional durability to the motorized drivetrain

the second half of the week was spent testing the trike-sans-engine and getting parts for the final prototype; i spent the better part of 2 days in town again, walking around river road finding exceptionally long brake cable and a sprocket that fit our system for mounting to the drive wheel (among other things); though most items were easier to find the second time around due to knowing exactly what we wanted and having a better idea of where to get it, i spent most of my time checking inner hole diameters on countless rear-wheel motorcycle sprockets (the inner hole had to fit around a standard bicycle freewheel; so many sprockets were close, only one was right) ... with the end of our stay in nairobi looming ever closer, we were glad to find relative success in the trike-sans-engine with proof-of-concept in brakes and chain tensioning system; with this knowledge, we began the work of assembling the final prototype: getting a new trike frame, adding handlebars and frame pieces, making a couple new chain tensioning devices, and making sure sprockets were mounted concentrically on their respective axles

there was some work on the write-up for final production by APDK and presentation to MIT people, but much of that will be done next week after we finish the final prototype (minus engine and mounting) and while we wait for the arrival of the engine ... we have received several reports from previous contacts of engines that "match our specifications," but upon further questioning, there are always one or two things that don't actually match up exactly; however, the guys at "riders kenya ltd." who were extremely helpful when we first visited (understood what we were looking for and talked about being able to order from china) have contacted us about looking at an engine at the beginning of next week; though i remain highly doubtful (possibly even pessimistic), i have hope in their ability and understanding of our project ...