This is my new lightweight urban commuter (a.k.a. MARTA bike). I purchased a used carbon fiber frame, and a used mountain bike frame that had been made into a single speed road bike and combined all the parts (plus a few extra) into a lightweight single speed bike. The frame is designed for road tires, and the clearance is very tight, so I am limited to a thin road tire on the back.
The mountain bike frame came with a standard MTB crankset, and I’m using the middle gear (34 teeth) to a 16 tooth rear cog (4.3 gain ratio). This combination makes it easy to get to the MARTA station without too much effort (don’t want to arrive at work all sweaty). I have also experimented with using the larger (42 tooth) sprocket and a 15 tooth rear cog for a 5.7 gain ratio, but that combination only works in the winter when overheating isn’t an issue. Because it’s a commuter bike, I added a LED headlight (held on with a hose clamp) and a detachable RavX Super Sight bicycle taillight. The running weight is 18.6 lbs, or 21.2 lbs when I carry a U-Lock.
Parts Details:
Vitus Plus Carbone (Carbon Fiber frame) 55cm 21.6″ (1988)
Vitus Dural 979 aluminum fork, Cinteli Stem, 26.4 Cinelli Bars
Front Wheel: Ritchey HB 575 Rim (26×1.0 tire)
Rear Wheel: Ritchey Hub ZER system, AERO OCR wheel 6061 T-6 Alloy
ETRTO: 622-14, Tire: Vlittoria Zalfiro 25-622 700x25c
Shimano Ultegra 6600 brake on back, “Schwin Approved” calipers on front, Tektro Reverse Alloy TT Brake Levers
Shimano Bottom Bracket, Square Taper 68mmx118mm UN54
RavX Rear Flasher, Front LED light
damn that’s an ugly thing. all the better for locking up. what became of the electric bike?
fwiw, you can readily pull the shift levers and bosses to save a bit more weight.
Sam,
Yep, nothing says “don’t bother stealing me” like hose clamps and random mountain bike parts.
I still have the electric bike, which weighs in at 3 times (60 lbs) the weight. This guy is a LOT more fun to zip around on. As we reach the heat of summer (July/Aug) here in Atlanta I’ll be evaluating my ability to petal (uphill) to the MARTA station without getting too sweaty. I may have to switch back to the solar electric bike for the summers. As this is when solar charging works the best, it may work out well. Otherwise, I may have to sell it off.
It would have been nice if my trip into work was downhill, but oh well.
W.R.T shifters – I tried taking them off but ran into a really tight bolt. Because I have considered putting a 3-speed hub on the rear wheel, I decided to not try and force it, as I may want the shifter in the future. And really, the weight savings is relatively negligible.
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