25mm tires vs "Endurance" bike

[mrhogghead]

Looking for some feedback on making my bike more comfortable. I have a degenerating disk in my lower back. I am a "Clyde" that rides a 07 Tarmac Pro. I absolutely love my bike but I get the ole aching pain in then back on longer rides. I was considering buying a "endurance" frame set i.e. (Roubaix, R3, 566) but have been told that I can achieve a bit more vertical compliance by just changing my tires from 23's to 25's and that I wouldn't really lose that much in rolling resistance and wieght. Suggestions? Opinions? Thanks!

 

[frenchyge]

You definitely won't hurt the rolling resistance or weight, but I don't know how much it'll help your back.

A wider version of the same tire and same pressure actually has less rolling resistance (although slightly more aero resistance).

 

[toomanybikes]

Tires and wheels make more difference to the "comfort" of a bike than anything else.

The real benefit of going to a wider tire, is running it at a lower pressure.

 

[mrhogghead]

My back isn't effected by positioning on the bike. It is actually a benifit to be on the drops. The problem is the verticle vibration. I'm just trying to rationalize the marketing of the "endurance" market. If you look at all the specs, they all run 25mm tires.

I understand the whole volumn/pressure thing. Where I get confused is if a lower oreassure provides the same resistance, then is it really more verticly complient? I'm going to make the switch and see. A new set of tires is relatively inexpensive as compared to a Roubaix SL2 or Cervelo R3. I'm a little worried about the durability of the R3 with a guy of my size and strength hammering it.

A better investment might be wheels? I currently run the stock Mavic Elites my bike came with. They are an excellent wheel for a rider of my caliber. Any suggestions on a good quality wheel that can give me what I am looking for while taking the abuse of 220#'s? I briefly rode a buddy's 404's. Wow! What about the Neuvation carbon clinchers or the new Dura Ace? Thanks again!

 

[toomanybikes]

At 220 lbs and with back issues you should not, IMO, be looking at factory wheels that are designed for racing.

These wheels will not give you any respite from the pounding and any benefit you get from higer volume tires will be offset by the increased "stiffness" ( the overused, overhyped nonsense bike stuff of this decade) of the wheels.

What you probably should be looking at is a set of handbuilt wheels with a higher spoke count to take some of the "buzz" off the ride for you.

I would suggest you contact Peter@Vecchios who posts here a lot, or contact Joe Young who builds wheels.

Tell them your back issues, your weight, and what you are looking for. Then listen to what they recommend.

 

[alfeng]

My back isn't effected by positioning on the bike. It is actually a benifit to be on the drops. The problem is the verticle vibration. I'm just trying to rationalize the marketing of the "endurance" market. If you look at all the specs, they all run 25mm tires.

I understand the whole volumn/pressure thing. Where I get confused is if a lower oreassure provides the same resistance, then is it really more verticly complient? I'm going to make the switch and see. A new set of tires is relatively inexpensive as compared to a Roubaix SL2 or Cervelo R3. I'm a little worried about the durability of the R3 with a guy of my size and strength hammering it.

A better investment might be wheels? I currently run the stock Mavic Elites my bike came with. They are an excellent wheel for a rider of my caliber. Any suggestions on a good quality wheel that can give me what I am looking for while taking the abuse of 220#'s? I briefly rode a buddy's 404's. Wow! What about the Neuvation carbon clinchers or the new Dura Ace? Thanks again!

I don't think that going with a wheel with a stiffer rim will be a benefit ... in fact, you would probably want a low profile, 36h rim laced x4.

I don't know what you mean by an "endurance" frame ...

You may want to consider a suspension seat post which uses a parallelogram (e.g., Thudbuster or TrickyDick) OR a frame whose chainstays are in the 17+ inch range OR both -- think "stoker" on a tandem and/or "touring" frame.

 

[frenchyge]

I understand the whole volumn/pressure thing. Where I get confused is if a lower oreassure provides the same resistance, then is it really more verticly complient?

If you run a lower pressure, then it'll be provide more cushion. The reason the rolling resistance *might not* suffer is explained here: Tech Center

 

[doctorSpoc]

My back isn't effected by positioning on the bike. It is actually a benifit to be on the drops. The problem is the verticle vibration. I'm just trying to rationalize the marketing of the "endurance" market. If you look at all the specs, they all run 25mm tires.

I understand the whole volumn/pressure thing. Where I get confused is if a lower oreassure provides the same resistance, then is it really more verticly complient? I'm going to make the switch and see. A new set of tires is relatively inexpensive as compared to a Roubaix SL2 or Cervelo R3. I'm a little worried about the durability of the R3 with a guy of my size and strength hammering it.

A better investment might be wheels? I currently run the stock Mavic Elites my bike came with. They are an excellent wheel for a rider of my caliber. Any suggestions on a good quality wheel that can give me what I am looking for while taking the abuse of 220#'s? I briefly rode a buddy's 404's. Wow! What about the Neuvation carbon clinchers or the new Dura Ace? Thanks again!

rolling resistance is primarily a matter of the energy lost do to the tire carcass flexing. the wider tire the shallower the curvature of the tire with the ground and the less the tire carcass flexes at a given pressure. as well you can imagine that the shape of the contact patch for the wider tire is closer to a circle and the thinner the tire the more elongated and elliptical the contact patch is. the longer, elliptical contact patch with more sharply bent carcass of the thinner tire results in more rolling resistance at a given pressure.

but the trick for comfort is not to run the wider tires at the same pressure as you ran the thinner ones, but to run them at a lower pressure. since the wider tires have lower rolling resistance at that lower pressure you won't end up losing anything in terms of rolling resistance. you basically are forced to run thin tires at a higher more bone jaring pressure to avoid pinch flats.. but you can run the wider tires at lower pressure since the contact patch is bigger and holds up more weight and won't pinch at that lower pressure... also the tire also puts the rim a little physically farther from the road compared to the thinner tire so makes pinch flats that much harder to get.

so when you go with the wider tires you gain more comfort with no penalty in rolling resistance.. and it's just not comfort. there is a performance gain as well since muscles that have been vibrated that much more all day like that are beat up and more worn down than those that have had a smoother time of it all day... the wider more comfortable tires will result in you being fresher after x hrs on the road compared to the thinner ones... also you get a bigger contact patch so you get more sure footed handling around corners and in rain.. lots of upside

the only down side that others alluded to is that you do give up some in aerodynamics since the tire is wider and has a larger frontal area and a less aero shape.. but as you can see the upside above in most cases more than makes up for this downside..

 

[mrhogghead]

All VERY good advice and confirmed my assumptions. Just to clarify, what I meant by "endurance bike" is a frame constructed with supposed more vertical compliance then my Tarmac. Such as a Specialized Roubaix, Cervelo R3, or Look 566. I have no doubt that these frames will give me greater comfort. How much comfort is the question? And can I achieve the same level of comfort by switching to a tire with a larger cross section and lowering the pressure? Also, by possibly switching out my wheels? Tires are cheap as compared to a new frame. A wheel set wouldn't be that bad (depending). And if I really need it, I can purchase the frame later.

Any suggestions on a good build for a wheel set? And am I correct in assuming that with a higher spoke count you would use less tention to keep the wheel true there by giving a more complaint ride? I'm thinking like a Dura Ace/Open Pro set up?
Thanks again!

 

[oldbobcat]

All VERY good advice and confirmed my assumptions. Just to clarify, what I meant by "endurance bike" is a frame constructed with supposed more vertical compliance then my Tarmac. Such as a Specialized Roubaix, Cervelo R3, or Look 566.

If you're happy with the fit of your Tarmac, then the Roubaix would be your best bet for a new frame. The "Zertz" inserts really work and the geometry mirrors the Tarmac with just a slacker head angle and a taller head tube. With the Roubaix you really just have to make sure you can set the handlebar low enough.

The R3 and 566 feature shortened top tubes as well as extended and slackened and extended head tubes, but behind the front wheel, the geometries are the same. From what you're saying, shorter reach might be disastrous for you. There may be some benefits for you in the materials--for example, the pencil-thin seat stays on the R3, but try before you buy.

And the best advice I can give is to first have someone build you a set of more compliant wheels--f'rinstance, 36 spokes, double-butted, 4x, low-flange hubs, with low profile rims and 25 mm high-thread-count tires.

 

[doctorSpoc]

All VERY good advice and confirmed my assumptions. Just to clarify, what I meant by "endurance bike" is a frame constructed with supposed more vertical compliance then my Tarmac. Such as a Specialized Roubaix, Cervelo R3, or Look 566. I have no doubt that these frames will give me greater comfort. How much comfort is the question? And can I achieve the same level of comfort by switching to a tire with a larger cross section and lowering the pressure? Also, by possibly switching out my wheels? Tires are cheap as compared to a new frame. A wheel set wouldn't be that bad (depending). And if I really need it, I can purchase the frame later.

Any suggestions on a good build for a wheel set? And am I correct in assuming that with a higher spoke count you would use less tention to keep the wheel true there by giving a more complaint ride? I'm thinking like a Dura Ace/Open Pro set up?
Thanks again!

why don't you just try the fatter tires first for a start? it's super easy and super cheap to try and has a high likelihood of doing the trick.. unless the real culprit is your bike fit or unless you are just hell bent on burning a lot of cash

 

[dhk2]

If you're a 220 lb clyde with back issues who rides on rough and course-textured roads, have to ask why are you focused on road race frames and wheels? You can spend big money on a custom steel or ti frame designed for comfort or touring (eg, Rivendall or Waterford) and have durable, comfortable wheels built for you with fancy hubs and rims that accept whatever tire width you specify. Plenty of lower-cost options as well for a bike that will give you comfort enjoyment for a lifetime of recreational riding and touring.

 

[lanierb]

Two comments:

1) If I were you I would see a pro fitter. It's about $300 or so and will be the best money you ever spent on your bike (though chances are you will have to spend more to change things around a bit too, but it will be well worth it). I realize you said the problem is from jarring bumps and not from fit, but I would do it anyway. Chances are a better fit will help too.

2) Larger tires will help a *little*. I use 23mm but I've also used 25mm and not sure I could tell the difference. There is also such thing as a suspended seatpost which builds springs into the seatpost. You could look into that too.