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The 1997 "Enterprise II" HPB

This year I hoped to have the new drivetrain bulletproofed. I fixed the skipping bevel gear problem (the gear was too far away from the bearing) and put a plywood section around the bottom bracket assembly. to prevent the BB from ripping out of the boom. Testing on the water proved it to be a marked improvement, and the drivetrain felt much smoother and more efficient than the old twisted chain affair. This one seems fast.

Everything was working well, and I took the boat to the 1997 Rockford Raft Race (July 4th). Tooling around before the event, the drivetrain seemed solid, but when the bomb went off, signaling the start of the race, the bracket that keeps the drivetrain fixed in position underwater broke, allowing it to swing forward. It took a couple minutes to rig up a rope to keep the drivetrain in place, and I managed to finish in 5th place. Bob Buerger finished first, some guy in a homebuilt kayak was second, and a bunch of guys in a homebuilt canoe were third. I'll be working to get the brackets reinforced for the August 23rd HydroBowl race...

HydroBowl Race update - Yes of course I broke it again. I was cranking hard on it before the Hydrobowl event, and was cruising, when the pivot around the upper bevel gears snapped. I'm beginning to question my decision to build so much of the drivetrain from composite materials. The forces placed on the pivot point that the top gears are in has been estimated to be over 600 lbs due to the lever and fulcrum effect of the drive unit underwater. This time the brackets held fine, but the pivot point itself broke. I will need to reconstruct this item out of welded aluminum or steel... 1998 races here I come!

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