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Impact of Tire Quality on Ride Comfort

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Impact of Tire Quality on Ride Comfort

Old 09-29-21, 09:00 AM
  #76  
Harold74
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Originally Posted by ofajen View Post
My comment is that I totally avoid this approach and have great success.
Thanks for you comments Otto. When I read your description of what you do, it frankly sounds almost identical to the weightless riding model that I proposed above with one modification: your definition of "getting low". Every rider has different comfort issues in play including flexibility and back health. I suffer from both of those maladies and, as a result, my own "getting low" isn't all that low. Given that, I am lucky to not have problems with my hands. I can tolerate my bars a couple of inches lower than my saddle only because my arms are disproportionately long. My back to thigh angle remains what one would expect from a more upright ride.

My wife's physiology, as a cyclist, is markedly different from mine (and yours by the sound of it). She has no back health issues and is almost ridiculously flexible. But she's got the hand problems. This is why I speculate that a lower riding posture for her might make sense as it would tend to wind up the "spring" that her hips represent. My belief in this hinges upon my skepticism of the core stabilization concept which I'll get to later.

Originally Posted by ofajen View Post
...when I do bear weight I keep the bearing surface more on my thumbs and off the middle of the palms as much as possible.
When you say that you keep the bearing surface on your thumbs, you really man the parts of your palms directly below the base of your thumbs, right? It's hard to envision one having strong enough thumbs that they could support themselves from them for any length of time.

Originally Posted by ofajen View Post
...wear my core muscles out supporting the cantilevered weight. Getting low just makes that unbearable and more exhausting and bending the spine like that is not what my body wants to do for comfortable riding.
This is the part that I take exception to. And I've seen similar propositions in a number of places. It seems to me that doing, effectively, a continuous reverse situp for the duration of, say, a three hour ride would range somewhere between impossible and highly unpleasant for most folks. Rather, when one is doing the weightless riding thing, I suspect that the "cantilever" is supported not by a health contraction of the low back muscles but, rather, their use in passive tension. In this sense, the posture is sadly reminiscent of slouching in one's office chair. This jives with the observation that folks with low back pain don't love, and are not well served by, the classic road bike riding position.

For casual riders willing to sacrifice a little wind drag in favor of comfort and back health, it seems to me that a much better road bike riding position is really the formation of an upper body, shallow arch "bridge" rather than the weightless cantilever. Unfortunately for the folks with hand pain issues, this requires the transfer of some degree of force from the handle bars and into the hands. Rather than attempting to ride weightless, I feel that it's more realistic for casual riders to use some of the concepts of weightless riding to minimize any unnecessary force generation in the hands beyond that which would be required to stabilize the upper body without attempting to 100% cantilever from the hips.
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Old 10-01-21, 04:21 PM
  #77  
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Originally Posted by Harold74 View Post
So I've been doing some research and testing (on myself) on this and I believe that I have a working theory of how to improve hand comfort for folks like my wife. I acknowledge that some of it runs counter to a lot of the reputable advice that you find out in the cybersphere.

Principle #1: dampening vibration is great but, to really help CTS folks, you need to get the weight off of the hands, not just dampen the vibration.

Principle #2. the key to getting the weight off of your hands, on a road bike at least, lies in adopting a posture that creates a near-weightless riding condition at the handle bars. Per the sketches shown below, I feel that there are two ways to accomplish this:

2a) Put some real force into the pedals. Not mashing, but forceful riding. I've noticed that it's harder for me to get weightless when I'm riding casually. This makes sense to me from an 8th grade physics perspective.

2b) Get low. As shown below, getting low winds up the spring that allows your body to cantilever from the saddle rather than span from saddle to bars. Again, this matches my experience on my own bike.

3) Based on the above, I do question whether it is universally advisable to raise the bars to help with CTS and hand comfort. It seems to me that doing so would yield one of two results:

3a) If you're riding weighted, then you shift your center of gravity back and lessen the weight on your hands. I see this as pretty much worthless for road bikes unless you raise the bar A LOT, which leads into the answer being an entirely different kind of bike. Raising the bars modestly simply does not shift the rider's center of gravity enough to make a real difference. Also, if feel that shortening reach is likely to be more effective at shifting the center of gravity than is increasing stack.

3b) If you're riding weightless, raising the bars unwinds the all important spring shown in the sketch below which diminishes the rider's ability to cantilever from the saddle.

I'm interested in hearing everyone's opinions about these ideas, particularly the dissenting opinions.


All your points are well taken and presented.
The counter balance of forceful pedaling is certainly an important way to 'lighten' the load on the hands. But, except for racers racing, most of us spend a significant amount of time riding at moderate levels which don;t quite make it into 'forceful' - so core fitness is a key element to supporting a rider who has some body lean forward.
Again there are many riders who don;t have the core fitness AND might be carrying more mass/weight in the front of their torso. It's a tough thing for them to find some balance between all these elements - often addressed by Higher Bar and shorter stem. Neither of which have a really adequate/great effect. SO more upright in whatever fashion is possible, with more weight ont the saddle. That's gotta be very uncomfortable.
Many also move the saddle forward, thinking that 'forward' allows more 'upright', which then exacerbates the 'A' frame bracing and shock thru arms and rear.
But if same riders could focus on small incremental changes to posture, over time, and thereby also strengthen their core/themselves. As you mention, relief can happen, in small steps.
'Sport' cycling is a fitness game, and our own 'condition' and 'reality' is brought clearly into focus, with every ride....
Not the end all or be all (time on a cruiser, or any other bicycle can be as rewarding, just different...).
Ride On
Yuri
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Old 10-01-21, 04:43 PM
  #78  
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Originally Posted by Harold74 View Post
Thanks for you comments Otto. When I read your description of what you do, it frankly sounds almost identical to the weightless riding model that I proposed above with one modification: your definition of "getting low". Every rider has different comfort issues in play including flexibility and back health. I suffer from both of those maladies and, as a result, my
What I do is actually different. Normal spine shape is actually curved back, not forward, in the lower back, and I try to keep that posture when walking, running, standing out of the saddle and riding seated. I keep my back fairly straight pretty much all the time, bend my elbows, and tilt my pelvis forward a bit and shift back on the saddle if Iím moving my hand position forward. I really do purposely avoid hunching forward.

Yes, as far as hand position, Iím mostly using the part of the palm that is also part of the thumb, the point being to keep pressure off the major nerves in the center of the palm.

Yes, I really use my core to hold my position. We each get good at what we train for. Iím good at this. I can ride drop bars with a four inch drop and classic deep drops, but Iíd need to do it for a while to get my neck muscles strong again. And then I would have to go too fast on the flats for it to either work well on trails or work well with the SS gearing I ride. A less aero posture that still lets me work really hard is ideal. I canít imagine pedaling hard all hunched over and feeling comfortable or strong.

Iím not sure why you are referencing casual riders and their needs. Iím riding SS on an old MTB so my rides are demanding whenever there is a hill or a headwind.

Also, Iím using all parts of classic touring bars, so I have ways to adjust exactly how much load I have to support. And I stand a lot, and it works best to keep saddle and standing posture similar.

Otto
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Old 10-01-21, 08:06 PM
  #79  
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Originally Posted by Harold74 View Post
This is the part that I take exception to. And I've seen similar propositions in a number of places. It seems to me that doing, effectively, a continuous reverse situp for the duration of, say, a three hour ride would range somewhere between impossible and highly unpleasant for most folks.
Let me add a few comments. First, this is how I ride so I have plenty of practice to develop some strength and stamina for this style of riding.

But it also isnít always the same. My rides are full of changes in load and work. So there will be a time out of the saddle on a climb, maybe coast down, then pulling hard so that Iím pulling back, and the weight is on the pedals. Then some medium effort where Iím holding my upper body as I described. And I have bars that let me move forward or back from a hood like forward extension all the way back to the steering axis, so that load is adjustable.

And finally, yes after two or three hours of riding a heavy SS bike this way, my whole body will be exhausted and sometimes itís the upper body that gets tired first.

Otto
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Old 10-02-21, 06:40 PM
  #80  
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My wife’s bike just got a change from Vittoria Corsa G to Rene Herse Chinook Pass Extralight. I mean just, as in since you started this thread. The Vittoria were worn out. They are simply great tires. Ten years ago, or more, if you wanted tires that rode as good as those Vittoria it was sewups only. And not all sewups, just the best ones. And as well worn tires those Vittoria were as soft as it gets. The RH tires are a big change. The wife has always been relatively insensitive to tire foibles so I was not expecting much. She just loves them. Yes, they ride like clouds. I was allowed a brief test ride. I would say the 700x28Extralight ride as comfy as the 700x32 RH Standard on one of my bikes. But just feel fast. All my RH tires feel fast. The only flat I’ve had was on a 700x44 used on the city bike that is abused horribly on glass-ridden streets and bashed through potholes and abused all winter. And when it finally flatted the tread was worn through anyway.

Anyway the Vittoria were 25s that run very large and the RH run a little narrow so same width within tenths of a millimeter. Hands down the RH are smoother.

No idea what sort of CTS your wife is coping with. Varies from a nasty nuisance to completely crippling. At high end CTS would be the end of bike riding. Talk to the therapist. Talk a lot. Therapists are like tires, not all the same. Get to know the therapist and get to know the therapy.

I will assume the CTS is long term. If you want to keep the lady healthy and riding it will take some investment. Bikes are way cheaper than doctors. Once orthopedic functionality is lost you would pay anything to have a little piece of it back. So start thinking about the best bike imaginable.

That Norco is a boneshaker. A small person does not need oversized aluminum tubes. Disc brake forks are automatically extra stiff. Flexible frames are possible in Ti and carbon, the main vocabulary of custom frames is in old school small diameter steel tubes. Forks made of Kaisei Toei Special blades with plenty of rake will give almost as much travel as that stem (which is a great item too). The flexy fork isolates shock long before it makes it to the stem. Compared to that Norco any custom will be much lighter, even if steel. Think of the bike as being a hammer working on butt and hands. A lighter hammer does less damage. And a light bike always feels nicer.

Lots that could be done. Do the tires as a first step and then figure there are another half dozen steps to go. And expect that it all gets better with each step. Tires are a big big step. Good luck.
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Old 10-02-21, 06:58 PM
  #81  
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A couple of other ways to get weight off hands. One is to use elbows on the handlebars instead of hands. Most would want the sort of armrest that comes with TT bars. You may also want to use shorty loop TT bars of some type. When lots of weight is on elbows or forearms not much weight is left on hands. Some few riders can do it with no special equipment, just elbows on the ‘bar and go. Those few are also the ones who can hold up their torsos just with core strength.

The other is to pull back on the bars. Hold the bars in same position as always but pull back instead of leaning down. Opens up space in the joints when you pull. Would it open up space in carpal tunnel? Could be worth a try.
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Old 10-02-21, 08:10 PM
  #82  
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My experience is that different tires using different rubber compounds and whatnot will also impact ride quality other than just tire size.
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Old 10-02-21, 08:48 PM
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Hereís a nearly current photo of my MTB. Notice the touring style handlebars and their relation to the steering axis and saddle height. With a 150 mm stem, the Albatross/North Road bar puts the grip position at about the steering axis. Depending on what one has for shifters, hands can be advanced forward to equate to drop bar tops or ramps or even hoods by moving to the forward bend.





Having this range of grip allows the rider a fair ability to adjust posture and weight balance between bars and saddle. Of course, not being able to use brifters means a rethink of shifting and possibly gearing, so for a current road bike this would be a rather big hurdle.

OTOH, a bike could be built with this cockpit in mind, perhaps with bar end shifters, coupled with other comfort options like the ability to run 2Ē tires. RH makes some really nice really wide tires for 26Ē, 27.5 and 29er wheels if you can stand the trouble of getting them properly on the rims.

The comment about using elbows may also be important. Iím not using them at the moment, but using a ďhorn barĒ style trekking bar is another option, and it can allow resting forearms on the bars near the stem clamp and holding the horn bar forward sections (with essentially no weight on the hands).

I prefer the touring bars because they give a better range of weight control for hand grips but if resting the elbows would be a significant fraction of riding, the horn bar might be preferred. A hornbar needs a short stem. Ergotec from Germany makes several versions.

Otto

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Old 10-02-21, 09:29 PM
  #84  
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Originally Posted by ofajen View Post
Hereís a nearly current photo of my MTB. Notice the touring style handlebars and their relation to the steering axis and saddle height. With a 150 mm stem, the Albatross/North Road bar puts the grip position at about the steering axis. Depending on what one has for shifters, hands can be advanced forward to equate to drop bar tops or ramps or even hoods by moving to the forward bend.





Having this range of grip allows the rider a fair ability to adjust posture and weight balance between bars and saddle. Of course, not being able to use brifters means a rethink of shifting and possibly gearing, so for a current road bike this would be a rather big hurdle.

OTOH, a bike could be built with this cockpit in mind, perhaps with bar end shifters, coupled with other comfort options like the ability to run 2Ē tires. RH makes some really nice really wide tires for 26Ē, 27.5 and 29er wheels if you can stand the trouble of getting them properly on the rims.

The comment about using elbows may also be important. Iím not using them at the moment, but using a ďhorn barĒ style trekking bar is another option, and it can allow resting forearms on the bars near the stem clamp and holding the horn bar forward sections (with essentially no weight on the hands).

I prefer the touring bars because they give a better range of weight control for hand grips but if resting the elbows would be a significant fraction of riding, the horn bar might be preferred. A hornbar needs a short stem. Ergotec from Germany makes several versions.

Otto
Now that, is a truly excellent setup. Where would I be able to find bars like this?

Does the positioning of your wrists when holding the grips feel comfortable?
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Old 10-02-21, 09:58 PM
  #85  
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Originally Posted by Moisture View Post
Now that, is a truly excellent setup. Where would I be able to find bars like this?

Does the positioning of your wrists when holding the grips feel comfortable?
I bought the inexpensive steel version, the Sunlite Elson Roadster, for proof of concept. The lighter, better, more expensive bar is the Nitto Albatross, which Rivbike, Soma and some other shops sell. Oh, Sunlite claim bar ends work with this bar. Thatís a lie. Bar ends do work with the Albatross.

The bars are comfortable as they are. There are grips and tape options that would be more cushiony that would be even better.

Also, as I mentioned before, with these bars, it seems to work best to ride with the thumb part of the palm bearing what weight there is, as much as possible, and avoid pressing on the main nerves. In all cases you would try to do something to keep from bearing weight on the main nerves.

Otto
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Old 10-03-21, 04:34 PM
  #86  
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Originally Posted by Harold74 View Post
So I've been doing some research and testing (on myself) on this and I believe that I have a working theory of how to improve hand comfort for folks like my wife. I acknowledge that some of it runs counter to a lot of the reputable advice that you find out in the cybersphere.

Principle #1: dampening vibration is great but, to really help CTS folks, you need to get the weight off of the hands, not just dampen the vibration.

Principle #2. the key to getting the weight off of your hands, on a road bike at least, lies in adopting a posture that creates a near-weightless riding condition at the handle bars. Per the sketches shown below, I feel that there are two ways to accomplish this:

2a) Put some real force into the pedals. Not mashing, but forceful riding. I've noticed that it's harder for me to get weightless when I'm riding casually. This makes sense to me from an 8th grade physics perspective.

2b) Get low. As shown below, getting low winds up the spring that allows your body to cantilever from the saddle rather than span from saddle to bars. Again, this matches my experience on my own bike.

3) Based on the above, I do question whether it is universally advisable to raise the bars to help with CTS and hand comfort. It seems to me that doing so would yield one of two results:

3a) If you're riding weighted, then you shift your center of gravity back and lessen the weight on your hands. I see this as pretty much worthless for road bikes unless you raise the bar A LOT, which leads into the answer being an entirely different kind of bike. Raising the bars modestly simply does not shift the rider's center of gravity enough to make a real difference. Also, if feel that shortening reach is likely to be more effective at shifting the center of gravity than is increasing stack.

3b) If you're riding weightless, raising the bars unwinds the all important spring shown in the sketch below which diminishes the rider's ability to cantilever from the saddle.

I'm interested in hearing everyone's opinions about these ideas, particularly the dissenting opinions.


Having the bars in a position where you can bend your arms while in your normal riding position is solid advice.

But this "coiled spring" idea - if I am understanding you right - is bad advice, IMO.

The only way your hips and back are going to act as a "spring" is when you have pushed them both to the limit of (and slightly beyond) their range of motion. The idea of using this to hold yourself up is a terrible idea. If your bars are so low that you are at the end of your range of motion such that you don't even need to use your core muscles or your arms to keep you in that position, then you are leaning way, WAY too far over.

When it comes down to it, the farther forward you lean, the more it takes to support your torso. And that support is going to come from either your hands/arms or your core. The idea of it coming from your bones and tendons being forced beyond there range of motion is asking for pain and injury. If someone really cannot put weight on their hands and really cannot use their core to support their upper body (which with a little bit of practice, most people can) then they ought to go for a much more upright position on the bike.

If the figure in the first pic it tilted at the hips as far as they are comfortable, then their position is good and they should try raising the bars to get some bend in the elbows.

That's my $0.02.
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Old 10-03-21, 04:46 PM
  #87  
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Originally Posted by Harold74 View Post
So I've been doing some research and testing (on myself) on this and I believe that I have a working theory of how to improve hand comfort for folks like my wife. I acknowledge that some of it runs counter to a lot of the reputable advice that you find out in the cybersphere.

Principle #1: dampening vibration is great but, to really help CTS folks, you need to get the weight off of the hands, not just dampen the vibration.

Principle #2. the key to getting the weight off of your hands, on a road bike at least, lies in adopting a posture that creates a near-weightless riding condition at the handle bars. Per the sketches shown below, I feel that there are two ways to accomplish this:

2a) Put some real force into the pedals. Not mashing, but forceful riding. I've noticed that it's harder for me to get weightless when I'm riding casually. This makes sense to me from an 8th grade physics perspective.

2b) Get low. As shown below, getting low winds up the spring that allows your body to cantilever from the saddle rather than span from saddle to bars. Again, this matches my experience on my own bike.

3) Based on the above, I do question whether it is universally advisable to raise the bars to help with CTS and hand comfort. It seems to me that doing so would yield one of two results:

3a) If you're riding weighted, then you shift your center of gravity back and lessen the weight on your hands. I see this as pretty much worthless for road bikes unless you raise the bar A LOT, which leads into the answer being an entirely different kind of bike. Raising the bars modestly simply does not shift the rider's center of gravity enough to make a real difference. Also, if feel that shortening reach is likely to be more effective at shifting the center of gravity than is increasing stack.

3b) If you're riding weightless, raising the bars unwinds the all important spring shown in the sketch below which diminishes the rider's ability to cantilever from the saddle.

I'm interested in hearing everyone's opinions about these ideas, particularly the dissenting opinions.


Where you are right is in understanding the rider has to do something. Buying stuff will not get the job done. And you understand it is necessary to try things and test ideas. Putting faith in hardware doesn't accomplish much.

Again, pull on the handlebars. Parking weight on the hands is bad even for healthy people. Be active on the bike. Do things. Ride that bike, donít let it take you for a ride.
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Old 10-03-21, 07:14 PM
  #88  
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How about slap on a pair of aero bars triathletes use? That take the weight completely off the wrist!

Sure she can't use it all the time. But if she use it half of the time, it'll help a great deal!
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Old 10-04-21, 08:27 PM
  #89  
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Originally Posted by Harold74 View Post
In some reviews of the Redshift Shockstopper stems, folks expressed their opinions that the system worked but expectations should be modest, on par with the switch from a 25c tire to a 28c tire. If it makes sense to do so, I seek stack the benefits of the stem combined with a larger tire.
With only going from a 25mm to a 28mm tire, you might also have to do a few other things to make an appreciable difference First, you'd have to get a supple tire for sure. Not sure about that Schwalbe. I have the Redshift stem on one of my bikes. It takes out the road buzz and mutes the larger bumps. I like it a lot. You might also double tape the handlebar and raise it (or flip the stem to a positive inclination) a bit so she is not putting so much weight on her wrists.
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