Internal Gears are coming

shimano-alfine-hub

Just got the word from Dave, Bike Guru of Redstone Cyclery that my New Alfine/Stans Flow 29er rear wheel has been built and ready for some offroad action. The single speed has been nice but for some of the longer exploratory rides I have planned it'll be nice to have some bailout gears as well as some bigger gears for those speedy descents.

I've always wanted a Rohloff as a singlespeed chainline with 14 gears has always been appealing due to low cost of maintenance after intial cost of the hub but $1500 for a hub alone was always a hard pill to swallow.

When word that Shimano's Nexus hubs were being used off road with success, I was intrigued but the lack of disc brake mounts still dissuaded me. Then about 2 years ago came word of Shimano releasing the Alfine. An internal geared hub that accepted Shimano's centerlock disc brake rotors. For the past two years I've read about guys putting them on Pugley's and riding sub arctic temps to seeing the goo mud guys in the UK have been abusing them in and none have yet reported a failure.

No pictures yet but I'll give you some gear ratios to pour over in the mean time...

Alfine Gear inch ratios 32x22 x 29" wheel

Estimated Shimano Alfine IGH gear chart using 32x22 chain/cog, 29 inch tire, 175 mm crankset. Gear Inch Ratios were figured into gear inches in white above using Sheldon Brown's Gear Calculator.

Total Gear Ratio Difference 3.07
Gear Ratio 1 0.527, Gear Inches 22.2, Equivilent cog size 41.8 or 22 chainring x 29 cog
Gear Ratio 2 0.644, Gear Inches 27.2, Equivilent cog size 34.1
Gear Ratio 3 0.748, Gear Inches 31.6, Equivilent cog size 29.4
Gear Ratio 4 0.851, Gear Inches 35.9, Equivilent cog size 25.85
Gear Ratio 5 1.0, Gear Inches 42.2, Equivilent cog size 22
Gear Ratio 6 1.223 Gear Inches 51.6, Equivilent cog size 18
Gear Ratio 7 1.419 Gear Inches 59.9, Equivilent cog size 15.5
Gear Ratio 8 1.615 Gear Inches 68.1, Equivilent cog size 13.63

The equivalent cog sizes were determined in yellow. Of course we all know there is no such thing as a 13.63 cog, nor any of the other fractioned cog sizes but it gives a good thought to perceived effort especially when gear inch ratio comes to mind.

I've read so much on the Alfine that I forgot the review but I'd have to agree from the above results that I'd use the Alfine like a geared singlespeed. I think the words they used after saying that was, "it may be considered oximoronic" but I can follow the train of thought in seeing that you may choose a gear and stay there since between some gears there can be as much as 22 percent difference. For the low price and the low cost of maintenance I'd consider that as acceptable. Time will tell as how well the Alfine can handle a load and reviews will be coming soon.

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