Goliath Frame
Goliath Frame

A project by Larry Lem

Concept Frame Bottom Fairing Top Fairing Cart-n-Rack Tail Battle Mountain

Goliath used dual 406 wheels with Shimano XT disk hubs, Sun Rynolite rims, and fat, Tioga Comp Pool tires. For the new bike, I wanted to use larger diameter wheels with narrower tires. As neither Tom nor I were up for the project of making narrow composite sandwich wheels (as all the fast guys were using), I decided to build narrow, traditional, hub and spoke 520 wheels with Specialized Mondo tires. I bought Sun ICI-1, 36h rims and Surly single-speed, disk-brake hubs.

To make narrow wheels to allow our legs to run alongside the hubs, Tom removed 1.43 inches from the center of one hub and I attempted to build the wheel with 14g spokes, 3X, and brass nipples. But during the build, the wheel kept wanting to taco so Tom modified another hub removing only 0.73 inches from the center. I was able to build this wheel, but it was still very weak and a little wider than desired. In the end, I decided to use the small diameter wheels already built for Goliath. This would allow us to maintain a low seat height and keep the backs of our legs above the cassettes and derailleurs. 
 I made a pair of seats from the Beluga seat plug.
Mar 08, 2008
As I was bonding fiberglass seat fronts to backs, I had difficulty keeping the seats square when clamping them together. One seat had a big enough twist that it required rework. I ground fiberglass off of the back, added more fiberglass and epoxy, and twisted the seat in the other direction as it cured. I overcompensated on the preload and had to do it again in the other direction. 
Apr 08, 2008
I decreased the stoker's seat angle to lower his head 2" below the captain's to allow for a gentle downward slope at the rear of the canopy. 
To determine where the middrives should be mounted to the frame, I mocked up setups with my lowracer, Beluga, and Goliath 1.
For tires, I estimated that skinny, fast Schawalbe Stelvios might not have sufficient load-carrying capacity but that fat, Tioga Comp Pools (shown here) would be wider than necessary. Tom Amick ran coast-down tests with an assortment of tires to determine their suitability and I selected 1.5" Greenspeed Scorchers. They were the best compromise in load-carrying capacity, width and rolling resistance. 
Jun 08, 2008
I had significant trouble with frame alignment despite using a jig. This resulted in the frame taking 3 months to build instead of a more sensible 3 weeks. Here, I'm repositioning the rear wheel for the 3rd or 4th time. 
I had difficulty with the rear frame section and dropouts but eventually worked things out. Heel clearance was an issue for the stoker. 
Funky rear dropout needed for derailleur clearance, 1/4" thick, 4130 steel……..third version. 
It took several tries to get the rear middrive placement correct. I needed leg clearance for the cassette but fairing clearance for the derailleur which would be sticking up in the air. 
I added a steering limiter to prevent the front tire from rubbing on the wheel hole cutout in the fairing. It was a brake bolt with a 1/4" bolt welded onto it, and a coupler nut welded onto that. 
Stops welded onto frame. They weren't too strong, but I never cranked the steering so hard that I bent the limiter. In fact, I don't recall ever hitting a stop while riding down 305 - which is a good thing, as running out of steering angle usually results in a crash. 
Final configuration - post-Battle Mountain photos. Stoker's drivetrain with 4" Fenner pulleys 
Stoker's seat, 9-spd Shimano XT shifters for middrives (both riders), SRAM Gripshift shifters for hub cassettes. (Gripshifts on "wrong" side of bars.) 5 cogs on middrives, 5 cogs on hub cassettes, 9 speeds, 8 shifts. 
 Captain's seat
A 5" pulley allows the chain to be aligned with steerer tube while the middrive cassette is positioned forward of my shin to reduce the overall height.

Next:  Bottom Fairing

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