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I'm building up an audax / light tourer on a budget and could use some advice on gearing choise.
Would picking up a 3x7 setup be completely daft nowadays? Say compared to sticking with old 2x6 road parts for now and updating to a more modern 10 speed setup later on? I expect the gearing on the 3x7 would be more suitable for my riding compared to a proper road setup, and the Q-factor of the chainset would be reasonably narrow. Going for 3x7 would mean building new wheels, though I've already got a pair of suitable rims in store.
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http://www.spincycleworks.com/servlet/the-157/CARBON-TUBULAR-50MM-HANDBUILT/Detail
Can anyone say anything bad about these?
Tester?buy these for 499?
http://www.planet-x-bikes.co.uk/i/q/WPPX52CCL/planet_x_52mm_carbon_clincher_wheelset -
^^^ What's your reason for wanting 3x7?
I'm sure it will be fine, but when 10 speed stuff is readily available and not that expensive, and 9 speed is even cheaper it seems odd to decline the gears when you need to build a new wheel.
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a modern compact double will give you all the gears you need.
My 2p: wait until you have the cash for the new group and stick with what you have until then - you'll end up upgrading to 10 speed anyway in the long run. Modern groupsets are miles and miles better than old ones.
Pretty much agree although if you're touring you may want a bit more range so there is merit to going 3x9/10 over a compact.
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I'm building up an audax / light tourer on a budget and could use some advice on gearing choise.
Would picking up a 3x7 setup be completely daft nowadays?
Like other said, 2x7 is more than enough, a 11-28 7 speed paired with a compact will give you a good range.
If very hilly - 11-32 will be plentiful.
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I've run 11-28 on 7 speed before. It's an arse if you're trying to keep up with people as the jumps between sprockets are quite large - try to get a 13-28 if that exists in 7 spd, If you're just touring, you'll likely never use the 11 or even 12.
^^ I think I'd rather have a compact double with a long cage mech / 32 sprocket than a triple. I am a bit of a tart about these things though.
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I have long femurs (according to Scherrit), so need the extra room- especially with a steep-ish seat tube. The exception is my track bike which has an inline seatpost and is set up to ride in the drops all the time with hips tipped further forward and more weight in my hands.
As far as I'm aware the distance from the bb to the saddle rails is the important measurement - you can achieve that by a combination of moving the saddle up or back. I have to choose more back than up as it gives me more room for the longer bones at the top of my legs, and takes pressure off my knees
Huh, interesting, now I want to know what the average femur length is for a 6'2" man...
I find things like this fascinating, seeing how the body and machine work together, and understanding how the sometimes relatively minor adjustments can make some huge differences in energy transfer and rider comfort.
Must get myself an appointment to see Scherrit at some point.
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Yeah it's a funny one - bike fitting never seems to end, it's always lots of marginal adjustments: will having my hards lower on the drops help descending? Do I want to be lower or longer? If I rotate my hips forward, can I use my glutes better?
Plus, it changes as you get fitter and more flexible. Four years ago my road bike was set up like an armchair!
When you get everything working in the right way it's such a beautiful thing, and you can concentrate on the job in hand rather than fighting the bike.
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It's indeed fascinating that my poor girlfriend was the victim of my experimentation of adjusting the bicycle and listening to her complaining (not that I did it on purpose), I also learnt that many fitting like the KOPS, handlebar in line with axles, etc. are about as useful as the BMI.
It's even more interesting when you're looking at very tall or small bicycle where the modern day geometry aren't always sufficent, Lennard Zinn's an example of trying to get the geometry right for those who's over average height;
What’s one major misconception of bicycles built for taller people, or in the construction of them?
Once you get to be an adult—at least with road bikes—basically everybody has the same length crank: 170-175mm, or even 165-180mm. With certain cranks, you can get that much range, but that’s still no kind of range relative to the difference in proportions of people. And then with wheel size, other than a few people riding 650B...smaller people can get away with smaller wheels... there’s no bigger wheels. Everyone’s got the same wheel size.
Now with mountain bikes you have a big range of wheel sizes, which is wonderful. I’m really happy about that.
One of the problems then, if you take someone as tall as me, and you’re going to fit them on a road bike with a 175mm crank, and you want to do the standard knee-over- pedal positioning, the seat has got to be way, way back over the bottom bracket in order to get the knee over the pedal. What you end up with really makes the bike terrible, in my estimation. You have a super-shallow seat angle in order to get the seat back far enough to get the rider’s knee over the pedal.
And what you end up with is the rider cantilevered way back over the rear wheel—weight distribution is awful. You have very little weight on the front wheel, and tons on the rear. It tends to wheelie the bike riding up steep climbs, and it doesn’t really have good weight distribution for handling on the descent.
And I think those bikes just generally do a disservice to tall riders and tend to discourage them from riding, because most tall bikes are too flimsy and too flexible. They just shimmy. And then with this positioning problem, the rider winds up super folded up at the hip angle because the seat is pushed so far back, and then the handlebars are not far enough forward and way too low. They’re just uncomfortable.
And that’s for a skinny tall guy! For a tall guy with a beer belly, it’s even worse! The shimmy is worse the heavier the rider gets. Those guys are the ones that really need to be riding a bike, and are the ones least comfortable and least safe on the thing.
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now I want to know what the average femur length is for a 6'2" man
There was a fit system described in Hinault's book which gave a mean ratio of femur length:height based on some anatomical study. I think mine were 107% of average for my height, based on the statistics in that book. I still have a bit of tape on the top tube of my bike from 1986 showing where my saddle nose should be based on that fitting method. /csb
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Thanks for the input.
The budget is more self imposed that out of necessity, and here's no other reason for thinking about the 3x7 except that I got a line on a decent set. But I think I'll pass and use what I have now to try out the setup and get an idea on the gearing range.
Cheers!
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I have a ahead system, but why would that matter?
http://www.sjscycles.co.uk/thorn-accessory-bar-t-shaped-105-mm-extension-0-deg-prod11040/
bring the handlebar bag lower.
Or get something like this to raise your light above the bag;
paradroid
dan
fredtc
hugo7
edscoble
AngelD
gbj_tester
Epam
plxarc
Sumo
Alfie-
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@emoxfag
No experience of them, but they look just like OS swept back bars. Which is good to know about.
edit: one thing I'm a bit confused about is what the brake size is. It says flat road brake or something, which I'd guess means 22.2mm, but I'd check first before buying.