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Martin, I would have thought that for rough roads and tracks you would prefer fairly wide-apart grips, rather than drops which generally come on quite narrow bars.

I get the widest available size of compact drop bars,about 46 cm wide. I find these are the best compromise for me for touring on mixed surfaces, if I was doing exclusively off-road I might go for something else.

I tried straight bars with bar-ends for about 1600 kms, but found the bar-ends a bit too wide, with the major disadvantage of not being able to brake quickly from this hand position.   
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You can have fun playing with this online bike calculator,

http://bikecalculator.com/index.html

Investigate how different positions  affect the other parameters.

I enjoyed your post, B. And you're right, playing with that calculator is fun. But, as George hints, at low available powers, what will make much more difference than even large improvements in aerodynamics, is reducing the mass the low power has to shift, what my cardiologist politically correctly calls "centre body mass".

As an aside, just taking the just-in-case painting gear always on the bike off, including its separate water bottle, would already make me faster...

As you also point out, at low speeds, body position is not hugely influential for touring or utility or just social riding -- the latter is important to me, and we average over a year almost exactly 16kph, which in turn is almost exactly 10mph. (Those German legislators who I excoriate at least once a year for banning blinkies would love us, because we go at almost exactly the speed they assume a German hausfrau pedals down to the shops.)

As for recliners, I find them psychologically oppressive. I had a semi-recliner once which I heard a bike shop in the city had in their store and bought on impulse, but it reminded me too much of driving a Porsche to the office and looking up at the wheel hubs of buses, which gave me nightmares, so I sold it on. But I can quite see that a recliner is a theoretically superior aerodynamic solution for a human-powered two-wheeler.

***

George, I love your friend's bullhorns. Thanks for posting the photo. I had a moustache bar once, the genuine thing from Nitto in Japan (a pain to source and expensive to get it here, but beautifully made) and the grips were so near parallel that I mounted it like an upside down bullhorn for some downhill speed trials. But even for that I found North Road bars more ergonomic though very likely, as they were wider, less aerodynamic. This was all done with a Gazelle proprietary stem with toolless adjustment of the handlebar. You threw a lever, rotated or otherwise shifted the handlbars to where you wanted them, threw the lever again, and rode on.

***

Martin, I would have thought that for rough roads and tracks you would prefer fairly wide-apart grips, rather than drops which generally come on quite narrow bars.
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One of my ailments is Spinal stenosis. I can only ride in one position using drop bars. I ride Ďon the hoodsí. Iíve tried straight type bars but these result is severe pain.  One reason (1) I donít go Rohloff is because of the lack of suitable handlebar.

I'm not suggesting that anyone actually changes what they do, John. Most of the people here are, I think, of a comfortable age where one can only marvel at their feats of athleticism in even contemplating riding a bicycle. It's not just habits that get set, it's bones and muscles too. You mess with proven habits at your perils.

On the subject of flat bars, I don't think their angles can ever be ergonomic. Just watch the angle of your wrists at any position where you can set up a flat bar. Your wrists should be straight. If aren't, you may be certain muscles up your arms and down your back are being unduly pulled, resulting in pain in the lower back.

It sounds like your position on the hoods is the best for keeping your back comfortable, and people shouldn't mess with your head for theoretical reasons.

Is the Giles Berthoud split drop bars for the Rohloff still offered?
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I used to use the drops maybe 5 percent of the time when I was really pushing into the wind, but could not do it very long.  Then I dropped about 15 percent of my body weight, much of it centered in the abdomen, I found it much easier to use the drops for longer periods of time once that extra girth was gone.  I think the change in girth really was the big difference.  Top of my drop bars is generally about the same as the top of the saddle, or maybe 5 to 10 mm below the saddle.

Most of the time I am riding on the hoods or if I want to sit up a bit, on the bar tops near the stem.  But when pushing into the wind I find I can usually keep a similar cadence and shift up one step on the cassette (eight speed 11/32, a step is generally 12 to 15 percent change in gearing) or one gear on the Rohloff (about 13 percent) if I switch from using the hoods to using the drops.  Thus, I am gaining somewhere between 10 and 15 percent in speed by using the drops.  There are some days in strong wind when I might use the drops for 30 to 50 percent of the ride for tens of miles.

With my bars as high as they are, when I am using the drops I am not leaning forward anywhere near as much as a racer.  So, no, I am not in a racing crouch with horizontal back.

Touring with panniers and stuff on top of the rear panniers, using the drops does not give me as much additional speed, but I still like to use the drops when pushing into the wind.  The extra stuff on the bike reduces the aerodynamic advantage of using the drop bars.

A friend of mine that is the same height as me but he weighs about 25 to 30 percent more than me (mostly abdominal girth) used to use drop bars but since he never used the drops he decided instead of trying to reduce weight, he would change his handlebars.  For the past six years he has toured on bullhorn bars instead, riding on the bullhorns is a posture that is very similar to riding on the hoods on drop bars.

I have had many different drop bar shapes over the years but the shape of the bars I have on my Nomad is the shape I like best.  A short reach so I do not have to lean too far forwards and a drop of roughly 13 cm.

First photo is the bars on my Nomad (hubbub adapter for my Rohloff shifter on the bar end), second photo is my friends bullhorn bars.


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Rohloff Internal Hub Gears / Re: Thinking of Gates Carbon
« Last post by energyman on January 15, 2019, 04:27:37 PM »
Some of the Riese & Muller belted bikes don't need splitters.  One justs drops the back wheel out to change the belt.  Clever ?
But at what a price !
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General Technical / Re: Nexus 8 v Alfine 8
« Last post by martinf on January 15, 2019, 02:44:34 PM »
One thing I don't like about the Nexus is that the gear changes are the opposite way to Rohloffs & Alfines

If that matters for you, a good reason to get Alfine rather than Nexus Premium.

I don't notice, as my Rohloffs have twist grip and I prefer the Rapidfire type control for my Nexus Premium bikes (Rapidfire control is supposed to be more precise and cause fewer mis-shifts due to slight differences in cable pull).

Wife prefers twist grip for her Nexus Premium bike, but mounted on the left instead of the more usual right hand side.
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Drop bars might offer more efficient locomotion -- I'm not so sure about that, actually -- but they can't ever be good for your back.

For long rides I prefer drop bars mounted fairly high up, so when riding the tops or the hoods I have a fairly similar back position to most of my other bikes with "straight" or "roadster" bars.

I'm fairly sure a crouched position as when using the lower position on drops is aerodynamically more efficient and that this makes a difference when riding at speeds over about 20 kph. It also gives at least a psychological boost when riding into a headwind for hours on end. Any aerodynamic gain is much less relevant when riding on the flat at fairly low speeds.

The main reason I use drops is for better hand comfort as it is easy to vary hand position. I spend most of the time on the hoods, hands parallel to the bikes axis. When I want a change I use the tops, hands at right angles to the bikes, or go down to the hooks, hands parallel to the bikes axis. I also use the hooks if I want to go fast or when riding into a head wind.

My Thorn utility bike now has "sit up and beg" bars, which allow a hand position vaguely similar to riding on the hoods of drop bars, hands parallel to the bikes axis. I have set this up to be slightly more uprght than my other bikes, so as to have a better view over the tops of cars. But I don't much like riding this bike for distances over about 50 kms as there is only one real hand position. And I feel my back more when riding more upright, the most comfortable back angle for me seems to be about 45į at age 62.
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Andre I agree with much of what you say.  Especially that many modern bikes are designed for a  riding position that is unsuitable for a significant numbers of people that buy them.  I also agree that for most  of us the aerodynamics of the bicycle hardly matter, but I can't agree that the aerodynamics of the rider don't have consequences. They do, and become  increasingly significant as speed increases. Moreover the difference between motor cars and bicycles is that the former have much bigger engines and hence more power.

Drag increases with the square of the speed and even more significantly the power to overcome it increases with the cube of the speed.  Between 10 and 20mph drag will increase fourfold and the power to overcome it will increase eightfold. Even if you rarely travel faster than 10mph a moderate 10mph headwind will have the same effect of doubling your apparent speed.

In a worse case scenario (Cd) in your expression CdA will equal 1. The key to reducing rider drag is to reduce frontal area (A), getting low into an aerodynamic position using drop bars is but one way of achieving this. Even greater gains, and comfort, can be gained by freeing oneself from the tyranny of the UCI and buying a recumbent.

You can have fun playing with this online bike calculator,

http://bikecalculator.com/index.html

Investigate how different positions  affect the other parameters.
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Rohloff Internal Hub Gears / Re: Thinking of Gates Carbon
« Last post by macspud on January 15, 2019, 11:08:35 AM »
I've never been lured by Koga bikes before but two things on that stand out for me - the sensible position of the bars, and of course the belt drive.  I may have to look a bit harder at newer options as the belt technology makes it's way to more and more touring products.  I'm no longer interested in any pro/con arguments about Gates carbon drives - I simply know that is the thing for me the same way I know that my heart is really only with Rohloff technology.  It's just how to get into a reasonable cost frame where I can simply move and adapt my current parts.

I appreciate every post on this matter, so thanks for the thread heads up horizon.  :)

I've never considered Koga as I've said, because I really value the Thorn brand, and steel is real.  I even like how they move slowly, though obviously that is what is causing my frustration at the same time. 

So one the one hand steel is real but on the other hand steel chains are real too. Real greasy or real rusty and a real pita always.

pavel, it seems that there have been some problems with the Rohloff splined carrier and gates cog.

I notice that Rohloff have now adapted their splined carrier for use with Gates Carbon Drive. They now have splined carriers with threaded lock rings:
https://www.rohloff.de/en/products/speedhub/accessories/

 
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One of my ailments is Spinal stenosis. I can only ride in one position using drop bars. I ride Ďon the hoodsí. Iíve tried straight type bars but these result is severe pain.  One reason (1) I donít go Rohloff is because of the lack of suitable handlebar.
Just my little bit of input today 😊
John
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