Another failed experiment
After too many encounters with the nasty chipseal roads in Clackamas County, and after a series of fenders met their doom due to toe overlap, I decided that when I built up a midlifecrisismobile, it would have 650b wheels and fattish tires. This was helped by QBP dumping some of their 650b wheelsets, which let me buy a pair of wheels at a ridiculously low price, and by a local bike shop selling Panaracer Nifty Swifties at < 20 a tire. So, in the fullness of time (and the fullness of selling things on Ebay, which let me accumulate enough money to buy a nice used lugged frame at a substantial discount from list price) I collected enough parts to assemble a midlifecrisismobile of my very own.
There were 4 things I wanted from a midlifecrisismobile
- Faster than the xtracycle.
- NO TOE OVERLAP, DAMNIT!
- smoother riding on chipseal roads.
- front-loading, ultimately with a porteur rack, but a handlebar bag would do as a short-term solution.
What I got was
- No toe overlap.
- Front-loading (though the joy of a high trail (==low rake) fork means that the front wheel really wants to flop off to one side or another. If I’d ever learned how to ride no-handed, this would have been a serious flaw, but as it is it’s just an annoyance.)
What I didn’t get was
- Speed. In the city/suburbs, I was getting (in 200-odd miles of test riding in the last week and a half) about ¼th mile an hour faster than the xtracycle. ¼th of a mile an hour is nothing to sneeze at, of course – If I could increase my moving average from 13mph to 13.25mph, that would cut 25 minutes of travel time off a R200 – but when I tried to ride the midlifecrisismobile on an actual R200, it ended up riding so slowly that I couldn’t even make the 80-km control before closing time. I’m guessing that the speed improvements I was seeing in town was because the lighter bicycle accelerates faster up to its slothful cruising speed (and maybe because it was climbing short ramps faster; it certainly does not climb longer ramps any faster than the xtra does.)
- Smoother riding. Now, I don’t know if this is an artifact of the wheels or if it’s an artifact of the shorter wheelbase of a bobtail bike, but those chipseal roads really pounded my arms and bottom when I was creeping up and down the county roads this morning. So, no matter what the cause, this has to count as a NO NO NO to whether it made the ride any smoother.
Now, I can probably live with a rough ride if I get it in exchange for a considerably faster bicycle, but a slower bike that has a rougher ride than the xtracycle? Um, no. My grand plan is that the midlifecrisismobile will be for riding those longer and more vertical brevets, and that plan will just not work if the d-mned thing runs so slowly that I can’t even make to the controls on time.
So it’s down into the basement with the midlifecrisismobile while I try to decide what to do with it. I have the original pair of 700c wheels off my Trek (rear wheel replaced with a 135mm axled wheel for the xtracycle, front wheel replaced with a generator hubbed wheel [originally from Amazon as a christmas present, then swapped for a fully built generaor wheel thanks to ebay and the ibob list]) and I could swap then in instead (after replacing the rear axle with a 130mm one to fit the modern frame) and see how they work out. I suppose I could move the xtracycle frame over to the new bicycle, then do a wheel swap to put the 650b wheels under the trek. And if worse came to worse I could just sell the parts on on ebay – the vast majority of the midlifecrisismobile is used parts, so I’d probably break even on the deal.
But, feh. It’s still annoying. It’s nice to not have to overlap, but maybe the way to do that is to get a cyclocross fork and rerake it to within an inch of its life. But I’m afraid the 650b’s are going to have to go.
Comments
Not really. The Trek has a very smooth ride compared to the mlcm, and it was a smooth rider even before I xtracycled it. The mlcm has the same geometry as the Trek, just expanded 3cm up and 6cm forward, so a sprung post (or sprung seat) seems like it would just be a band-aid to hide the real problem.
The smaller fatter wheels are the largest diversion from the Trek, so I’m considering them to be the prime suspect. They’re certainly the easiest thing to swap out for test purposes, since the only change required is to re-axle the rear wheel with an axle suitable for 130mm dropouts (and retruing – some of the spokes keep working loose during regular operation and need to be retensioned before I ride on it) and then to ride it on a suitably long loop.
I suspect that “fatter” may matter more than “smaller”, or, at least, going from hybrid smooth-middle-knobby-edge tires to much narrower “really fat for a road bike tires” made a big speed difference for me. (42mm to 28mm, I think.)
Hope you get a good solution!
FYI: Bicycle Quarterly did tire tests about 3 years ago, including the Nifty Swifty among several other 650b and 700c tires. The Swifties were among the slowest, least comfortable tires in the whole test, regardless of wheel size. The Panaracer Col de la Vie’s fared much better, as did the Mitsuboshi Trimlines (which, unfortunately, have been discontinued). They also liked the Grand Bois Hetre and Cypres models, but those are rather dear. You might think about trying some other rubber out before you give up on the concept entirely.
It just so happened that I bought a pair of CdlVs as cheap spare tires, which means that trying them out wouldn’t cost me anything. I’ll have to remove, with great force, the Nifty Swifties tomorrow and see how the CdlVs work in their place on a short loop.
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Have you considered a sprung seat post?
The tech seems to have reached a nicely mature state of reliability and utility.