Saturday, February 25, 2012

Gear Esoterica


No, I don't mean gear a la BPL. Or even paddling or ski gear (collectively known as WHITE water gear).

I mean gear as in bike gears and ratios between front and back for the kind of riding I like.

MC has shown me the amazing La Marg-rie combo and I want to put on a freewheel, one that will match my speed and terrain.

Last summer I experimented with a Middleburn ProTrials bashguard 16t up front and a White Industries DOS ENO freewheel 16/18t in the back. For shifting I used a wee old (1972) Campagnolo Nuovo Record der that is very short cage. What does that give me? It gives me shifting, simplicity, and plenty of clearance on brushy trails and rocky beaches/gravel bars. It gave me the two gear ratios I used the most -- or close to them -- from the old hellbiking days: 1.00 and 0.89

That set up was great on the beaches of the Lost Coast and would go on my bike again for that trip, except that I did want a slightly higher gear too: mostly to keep up with Doom.

Right now, daily I ride the same DOS ENO out back and a Middleburn double up front, 27 by 38. That combo works well for town riding summer and winter (for me). Summer time and when the winter roads are well plowed and icy I use the big chain ring on roads and the little chainring on trails. Winter time I use the 27t front and the 18t rear for soft trails and the 27t and 16t rear for harder ones. It's amazing (to me) what a gear difference of 0.2 does on "slow" surfaces like snow and wilderness trails and "trials".

But now I am planning a wheel-set for something more mountainous. My experience when off-trail (or animal trail/gravel bar riding) in wilderness mountains, is that most of a day is either down a drainage or up a drainage. In other words, I could get by with one DOS freewheel all day.

Heading up a drainage or riding caribou trails of North Slope gravel bars most of the day? Then go with a 17/19 t DOS in the back and 18 t Middleburn up front, giving nice low spin gears of 1.06 and 0.95. Heading downstream all day, where the major variability is going to be sand spinning or cobble plowing vs vegetated smooth pea-vine bars? Then go 16/18 t in back to push 1.00 and 1.13 ratio.

How to carry both? two rear wheels. One run as front one run as back, swapped appropriate to the day's anticipated riding.

Of course my dream rig would be a 20/16t White Industries DOS ENO as that would give two versions of gearing that differs by 0.2.

4 comments:

  1. I second the desire for a wider range Dos Eno.

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  2. Hello,

    Great report. Inspired me to get a fatbike.

    But regarding the wider range freewheels. A possible solution is to use singlespeed freehub hubs. Like these: http://www.halorims.com/ison/image/complete/huha-xcd-ss-sil-set.jpg

    They allow you to choose your own gearing with several singlespeed cogs. I use Hope singlespeed/ trials hubs and I usually run 5 to 6 gears on them. The Halo has less space so you'll have stronger wheel. Also Chris King and DTSwiss have singlespeed freehubs. The latter two a quite a bit more expensive but they are ace quality. Hope has shitty seals. But you can open up en clean/regrease the pawls using just a plier and some body english.

    ReplyDelete
    Replies
    1. Thanks Alexander, that is a good idea and one that's been trickling in from other sources too.

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  3. Hi Roman!

    Have you considered Schlumpf Speed Drive or even High Speed Drive on the front? You get the advantage of 2 front cogs in one unit, easy shifting, no cables involved. http://www.schlumpf.ch/hp/schlumpf/faq.getriebe.engl.htm
    Also for the back I might try Sturmey Archer Duomatic http://www.sturmey-archer.com/products/hubs/cid/7/id/55 no cables, coaster brake and together with one of the Schlumpfs you would get 4 pretty reasonable settings.

    All the best!

    Mat

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