BlackMax

     This is going to be my effort to produce a purpose built performance trike.  While some of the other trikes I've built are fast too, they weren't built with speed in mind, so I'm going to naively assume that if I actually INTEND to build a trike for speed, I should get a little bit of a performance boost over the normal trikes like the 20/20 Heavy.  If all goes well, it'll be the prototype for the "Black Max V", my coroplast velomobile.  The main frame design will pretty much mirror the 20/20 Heavy because it's a nice tight frame, but it'll have a few small tweaks to it.  The vast majority of the "improvements" or tweaks will not involve spending extra money, rather they will involve just paying attention to a few details that I haven't made a priority in other builds.  Such as . . .

• the main frame rails will be stretched about 2".  This will allow me to lay the seat back to about the 25º mark which is more than far enough to get a better aero profile, but not so far as to hamper power output too much.
• I have some 406 aero profile 48 spoke wheels with 14mm axles and some really nice sealed bearings that my lovely wife bought for me about 4 years ago for Xmas.  I have been waiting for he right project to use them on and this is the project.
• I am up in the air yet over whether to use horizontal direct steering arms with modified brakes or a center flip-up tiller with indirect steering.  I will need some form of bulldozer-type steering or a central tiller in the velo version anyway, so I'll likely go that route but I am loathe to add all that extra pivoting junk.
• I salvaged some old high quality LH and RH threaded ball joints and will use those to absolutely fine tune the toe-in setting.  According to roll-out and CRR test by John Tetz on his trike, frame flex putting the toe-in settings out of whack was a big contributor to rolling resistance.  With my usual dual RH threaded rod ends, I am limited to about 1/8" accuracy which may or may not be good enough, but I'll use the paired ones to dial it in right to the Nth degree on this baby :)
• tweak the boom design so the right hand top tube is offset to the left about an inch.  This will allow me to run the chain down and under the crossmember where I can put a single, large pulley with good bearings and clean up the chainline as much as possible.  I'll also use a ¾" lower tube instead of the ½" I normally use to give it a little more stiffness to compensate (hopefully) for the offset boom tube.
• lastly, I'll lower the BB a little to try to keep the front end lower to the deck in anticipation of the velo version.  I'll also be adding a number of tabs at the back to help mount a more streamlined coro tailbox than the other two I've made.

     Weight? Not worried about it.  For my available supplies, cost and equipment, I'll be happy with my standard ~40lb trike weight.  Hills and acceleration will be dealt with by getting stronger, losing some "insulation" and making sure that I ride smart on race courses and pay attention to the lines.  I do not doubt the ability of one of my trikes to keep up with any commercially produced "race trike" out there.  I just hope the engine is up to the task :)

     For now, I'll continue to slowly collect the last few parts I need, and finish up the current 20/20 S.  I should be able to start the trike just before Xmas '07 if all goes to plan.

 The specs are the following:

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