Start Time 2:30
Moving Time: 0:41:00
Elevation(Ft): 0
Avg Spd(M): 10.5
Max Spd(M):
HR Avg(BPM):
HR Max(BPM):
Temp Out: 75
Temp In: 75
Afternoon:The wheelset came about 12:30. I unpacked it and started changing out the fixie wheels. The website said the rear over locknut dimension was 132mm but to my pleasant surprise it was about 120mm which means it slipped into place with no frame bending. I put the wheel on and looked on the Internet for instructions for installing the shift mechanism. It consists of a handlebar mounted twist shift, a cable, a pushrod and a cam mechanism to activate the pushrod. The pushrod goes into the drive side axle and the cam device slips over the end of the axle and pushrod and is locked in place by a set screw. I put this on then removed the old right side handlebar grip, moved th brake out of the way then mounted the shifter and a new shorter grip. Th grip is one of a sett that came with the twist shifters I have on my touring bike. I use bar tape ont hat bike so the grips have been sitting in my box waiting for a purpose. All that remained was to zip tie the cable to the frame, adjust the cable length and put the front wheel on. Soon enough I was ready to give it a test ride. New Wheel and Shift Cam Mounted:
Shifter and New Grip (I have since moved the computer to the lower section of the bar):
Shift Cam in Place:
Rear Wheel Ready to Go With Cable Tied to Frame:
I rode up and down the park before I realized I had made my standard error an left the computer magnet on he old wheel. I stopped at home and retrieved it then rode another 6+ miles in the park. I don't mind sticking close to home until I see that all is well. Near the end of the ride I stopped an re-adjusted the shift cable and it shifts like glass. The tires have no Stop Fla Strips yet and it is only a matter of time before one or both develop leaks from sticker punctures.
It is not the same bike but after this ride I am pretty much adapted to it. The wheels do not feel as solid as the fixie set and they are not perfect in true or tension. I will mess with them as time goes on to see how much I can improve them. In the meantime It is a fine bike to ride and the ability to downshift when turning into the wind or on a step pitch is a nice feature and my knees appreciate it already even before tackling a real hill.
Evening: 8:00 PMI napped from about 5:00 to 6:45 then went out for a short evening jaunt. I am liking the bike as it is more and more. I was concerned that to top gear would be too big/high for me but it feels about right and I really like being able to drop down to a lower ratio when needed. So far I have not been able to use first gear but it will probably allow me to get up most of the stuff around here with some blood sweat and tears. I weighed the bike and it came in at 21 pounds. I recorded 26 pounds when I first built the bike with the single speed wheels. That seems like too large a difference but I just weighed the SS wheels and they are 11 pounds with 2 freewheels installed, very heavy, very solid. Losing 5 pounds of bike weight is not a bad thing. Gearing:
I currently have six options for gearing this bike. I have 41 and 44 tooth chainrings and 16, 20 and 22 tooth cogs. The obvious combinations are 41/16, 41/20, 41/22, 44/16, 44/20 and 44/22. I like my gear numbers in Gear Inches which indicate the number of inches the rear wheel advances on the road per crank rotation. Gear Inch is a calculation based on Wheel and tire size (700x32), crank arm length (170mm), chainring size (41 or 44), cog size (16, 20 or 22) and in this case hub gear ratios (for a derailleur bike the various cogs on the cassette or freewheel are used in place of hub ratios). The ratios for the Nexus 3 speed hub are: 0.72 (low), 1.0, and 1.36 (high). I use the Sheldon Brown Gear Calculator to compute Gear Inches. It can be found HERE. The Gear Inches for my selection of cogs and rings are as follow: 41/16: 50.7, 59.2 and 94.2 41/20: 40.6, 55.4 and 75.5 41/22: 36.9, 50.3 and 68.6 44/16: 54.4, 74.3 and 101.3 44/20: 43.5, 59.4 and 81.0 44/22: 39.6, 54.0 and 73.7 41 and 44/16 can be eliminated out of hand because the high gear is just way to much for my old legs. The default single speed gearing is 46/16 which gives 105.9 Gear Inches. I use gears in that range on my road bike only on long steep downhills. I guess young guys can push those kind of numbers on the flat but I cannot. 44/22 is essentially the same as 41/20 so it is out. That leaves 41/20, 41/22 and 44/20 as legitimate possibilities. I am using 44/22 now and if my legs continue to improve I might get away with 41/20 or even 44/20 but I seriously doubt I will be able to get beyond that and that is fine with me. I do much better with lower gears and higher cadence than the reverse and it is much easier on knees and leg muscles. In summary I will use 41/22 for now and keep the option of changing the cog to 20 tooth in mind. Other possibilities include gearing this bike to pull a loaded trailer for touring. The largest cog available is 23 teeth which offers very little reduction over a 22 tooth. This leaves the next step to be a smaller chainring. A 34 tooth ring may be the smallest that will fit my crank: 34/23: 29.3, 39.9 and 54.4 This combination could make touring with a moderately loaded trailer a reasonable option. As as comparison my touring bike has a granny gear of 17.5 and a high of 108.0 with 25 other possibilities in between. I have not found a hill I could not get up or a grade I did not have a comfortable gear for with a total bike and luggage weight of 90-100 pounds. The touring bike alone weighs 38 pounds. The only way to find what the limits of a 3 speed geared for touring are is to try it.
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