Further Adventures In Homebuilding
Dual 700C High-racer
 
Way back in early ought 4, I published an article on homebuilt recumbents, well I finally got my very digital camera and some measure of skill at the computer so I can continue.

Yes I did in fact build all three designs and after many adventures came to some new conclusions and was therefore not satisfied. Here we now go back a coupla squares, but I think it’s worth it. So without further ado . . .

This is the DUAL 700c version 1
This bike turned out to be everything I wanted in the lowest rolling resistance, and is quite fast, although I don’t care for the high seat and bottom bracket or the tweener bars. We’ll take care of this later.
Details are:
48/44/24 Deore XT crankset moded to 155mm
11/30 8 spd Deore XT cassette
Sachs PC88R chain
Bacchetta tweener bars
Ultegra double front/SGS rear derailleur
Ultegra 36H hubs, DT revolution spokes
Maxxis road tire 700/23 120psi rear,700/20 130psi front
Easton EC 30 carbon 1” threaded fork
Ultegra rear brake/Dia Compe left side pull front
Sampson Ti BB w/replaceable sealed bearings
Hostel Shoppe seat bag
Power On/Swanson carbon seat (review later)
Front ¾ view showing:
Wellgo mg/cromo pedals 240 gms
Ultegra double front because I use half step gearing
20 year old Dia Compe with pull on left side
Stronglight Delta headset black
Alu crank bolts
Control Tech Ti/Alu skewers
Rear ¾ view showing:
Sachs pc88r drilled plates chain, bought in ’98
Chain rests on stay but when frame is loaded (with a body, preferably live)it doesn’t hit, but will sag and touch when power is relaxed (coasting)
Lack of drive side pulley makes it a bit hard to adjust derailleur though
Elastomer suspension unit according to original plan works with no problems.
Quick release SS pin allows for the rear stays to be folded forward when wheel is removed, a simple operation
FWD 650/700c Original Design
The BIG problem with this original design frame is the frame flex at the sharp joint behind the head tube, I figured I would ride it till something happened. After about 10 weeks the main tube cracked half way through just behind the lower head tube join. I rode it the 3 miles home slowly.
 After welding the crack I brazed a diagonal brace between the head tube and the down tube, this worked and I rode and raced it for a year with no further problems. However when I changed the front tire to a Conti 650/23 from the Vredestein 650/23 , the tire was a couple of millimeters larger in OD. There was originally enough frame clearance but that disappeared when I repaired the crack. Now every time I hit a big bump or braked hard the tire rubbed, this was not good.
2nd Generation FWD 650/700c
This frame was built in Sept ’05 for 2 reasons; To eliminate the front tire rub (this was really annoying) and to develop the all purpose frame for future designs.
Side view showing:

Big Cheese (QBP)/Dotek 155 mm cranks with bosses tapped for 74mm bolt circle to make triple
52/48/28 half step chainrings
11-30 8 spd Deore XT cassette
Front derailleur is OLD Deore half step
Ritchey pro pedals
Shimano UN 73 113mm BB
Ultegra SGS rear derailleur
Shimano RX ride side pull front brake
Stronglight A9 headset
This is a very comfortable ride, the only problem is the jack hammer like effect of the straight fork blades, I hope to the work out the bugs when this frame changes to a 700c front wheel
Pulleys are: 

Drive side; 95A durometer PU 2.5” OD stock from Mcmaster-Carr and machined to accept ½” ID double sealed radial bearings (2), held in place by AN bolt. This size is necessary to withstand the load.

Return pulley; a skateboard wheel turned for a chain channel and is a 5/16” bolt.

The rear view shows a rigid frame as the rear suspension is not really needed with a 700c tire, the rear suspension needs further development anyway. This bike weighs about 23lbs.

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