Teach me on gravelenture bikes

[Lorenzzo]

Watched something on PBS about cholesterol versus inflammation, specifically as a result of carnitine (amino acid from red meats) being processed by gut bacteria and producing trimethylamine (googled that bit..). Byproduct, inflammatory response and atherosclerosis. So I'd avoid the red meats, don't beat yourself up on your cholesterol numbers, don't take statins, stop doing 15 mile runs 6 days out of 7 and do more yoga, moderate weights, moderate cardio.

It's funny, in the old days when you worked hard to eat, you wore out early and died young. Now we want to replicate beating ourselves up! Sitting on your ass isn't good..neither is 10 marathons a year, apparenly.

He mentioned red meat is looking really bad in terms of risk. He did however extol statins and says there's now good evidence they don't just prevent additional build up but also smooth out and reverse even when calcification has been in the mix.

I can only parrot back what this one doctor said, I have some research to do. I'd bet some of this stuff will stick, some won't but certain research has been peer reviewed and duplicated mid to long term and so may carry a little more weight.

 

[Tom K.]

^^^Back to gravel bikes!

 

[cantunamunch]

It's not the red meat, it's what they are fed that is causing the problem. Get high quality grass fed or organic meats and enjoy.

Sadly all red meat - since all mammals except humans (and, since 2008, the pigs that were bred to mimic humans) have the specific sugar that presents cancer risk. But the good news is that the cancer risk is immune-system mediated. IOW when the immune system is not doing well risk is higher.

Chicken soup when sick, not burgers.

 

[Bill Talbot]

Another one of my gravel bikes. This one a '83 Bianchi Specialisima Cross platform

 

[Ron]

Since this has a great thread with a ton of good info, I thought I would include tire width efficiency into to the discussion. So it seems that going wider especially on our chip N' Seal, the 28's will of course be more comfortable but as efficient as a 25 if I reduce the pressure to 80-85 psi from my current 90-95. Since I am going from Schwalbe One Tubeless to Pro Ones, I am saving roughly 130 grams too

http://road.cc/content/feature/182519-trend-spotting-why-you-need-switch-wider-tyres

For those who don't want to read it all,

Quoted from Article.
"You’d like your tyres to roll as easily as possible but a certain amount of energy is lost through rolling resistance. Lots of factors determine rolling resistance, such as tyre width, profile, air pressure, material quality, and the constant deformation of the tyre as you ride.

“Wider tyres roll faster,” says Dave Taylor, Marketing Manager at tyre brand Schwalbe. “The answer lies in tyre deflection. Each tyre is flattened a little under load. This creates a flat contact area.

“At the same tyre pressure, a wide and a narrow tyre have the same contact area. A wide tyre is flattened over its width whereas a narrow tyre has a slimmer but longer contact area.

Contact area of a wide tyre © Schwalbe

“The flattened area can be considered as a counterweight to tyre rotation. Because of the longer flattened area of the narrow tyre, the wheel loses more of its roundness and produces more deformation during rotation. However, in the wide tyre, the radial length of the flattened area is shorter, making the tyre rounder and so it rolls better and therefore quicker.”

Contact area of a narrow tyre © Schwalbe

As Dave Taylor says, that’s when the wide tyre and the narrow tyre are pumped up to the same pressure. In truth, though, you’re likely to run a lower pressure in a wider tyre, increasing the size of the contact area. That will increase the rolling resistance above the level it would otherwise be, but according to figures from another tyre brand, Continental, a 20mm tyre with 160psi, a 23mm tyre at 123psi, a 25mm tyre at 94psi and a 28mm tyre at 80psi all have the same rolling resistance.

“In practice, the energy saving is even greater than in theory as the elasticity of the tyres absorbs road shocks, which would otherwise be transferred to the rider and so saves energy,” says Dave Taylor.

 

[Lorenzzo]

^^^ That's ireally nteresting and flies in the face of the local explanations I've heard. I guess shop bike experts aren't aware or might go with mud to avoid having to explain all that.

 

[Ron]

its similar to why wider tires are better for MTN biking as well. There's a point of course where sheer weight becomes a penalty for both road and mtn but in mtn there's really no aerodynamic penalty as in road. Having said that, the reality is that the aero penalty for road is really not an issue for about 90% of riders. I read one study that stated that between 23 and 25's the measurable or felt penalty didn't kick in until 27 MPH and that was very little.

 

[Bill Talbot]

Then there is the '06 Ritchey B-A Cross, this one has seen a bunch of CO action

 

[cantunamunch]

You don't run fenders on any of them?

With the drought we've been having I have to or everything from the water bottle to the bottom bracket is caked with fine grey cementlike dust.

 

[Bill Talbot]

You don't run fenders on any of them?

With the drought we've been having I have to or everything from the water bottle to the bottom bracket is caked with fine grey cementlike dust.

I can't stand the noise! The hose and bucket fix the rest...
I have fendered bikes, but not gravel bikes

 

[Bill Talbot]

As Dave Taylor says, that’s when the wide tyre and the narrow tyre are pumped up to the same pressure. In truth, though, you’re likely to run a lower pressure in a wider tyre, increasing the size of the contact area. That will increase the rolling resistance above the level it would otherwise be, but according to figures from another tyre brand, Continental, a 20mm tyre with 160psi, a 23mm tyre at 123psi, a 25mm tyre at 94psi and a 28mm tyre at 80psi all have the same rolling resistance.

“In practice, the energy saving is even greater than in theory as the elasticity of the tyres absorbs road shocks, which would otherwise be transferred to the rider and so saves energy,” says Dave Taylor.

I'm no lightweight @ 185# but those pressures are TOO high. I run around 80 psi in my 25mm tires and 60psi in my 35mm gravel tires.

 

[Josh Matta]

lower pressure does not always equal slower either. Especially when running a tubeless system. Deflection is the enemy of speed and the less you have it the better.

 

[Ron]

the bolded statement from Continental tires is showing the pressure required to equal Rolling Resistance (RR) to the narrower tire so the baseline was established on the most narrow, 20mm tire. all other PSI's were then equated after,
I agree for the narrower tire pressures but 80 psi on a 28 isn't too low for most circumstances and riders. And yep! tire deflection folks, tire deflection. but its a balance between just enough Pressure, too little or too much. you have to experiment. I will have the 28's rolling for weekend riding. I plan to start off at 80F/85R I will ride one of my regular rides so I will have a pretty good for handling, feedback and RR.

@GregMerz correctly says "if you think skiing is complicated, you need to look at cycling"

 

[skibob]

Just did about 15 on the rural roads. Its a mix of hard pack, some washboard, a little loose on the corners , 6" wide, 2-3" deep divots and ruts. I didn't really want to call these gravel roads because they aren't true, loose gravel. They are more like classic Gran fondo I let some extra air out of my tires ( I normally run 90F/95R) and although I certainly see how a 33-35 would be ideal, I really didn't have any issues. The GF carbon frame,bars and wheels really do a solid job of vibration mitigation and it a stable bike. Keeping a light touch on the bars is key too. I am looking forward to getting the Pro One 28's which should run at just about 30.5. I suspect running these at about 75-80 will make for a pretty decent ride which would be a good thing.


BTW- Moots is located here in Steamboat and their Gravel adventure bike is called the Routt (our county and play on words) This was really designed for exactly what I was looking for and it max's out at 35 tires. I would love to have one of these bikes! the "cheapo" build is $7,200 they also make a Routt 45 with corresponding tire clearance.

http://moots.com/bike/routt/

FWIW, the 28mm tires on my road bike, I run at 70R/65F and that is PLENTY for road riding. And I am ~200lbs. Of course, YMMV, but i would think you could go at least that low, if not lower if you are significantly lighter than me.

 

[skibob]

I think he's shooting at extreme endurance and its tendency to increase inflammation response. As opposed to moderate exercise, more resistance, less endurance and having appropriate rest time between. There is a train of thought as well that the true risk for heart disease is inflammation, not fats or cholesterol.

I agree with that concern 100%. But its always relative to your training level (which you maintain and/or work up to carefully). My buddy the former pro bike racer can climb a 3000' mountain on his bike. 3 times. If I did it once (if I made it) it would be a mistake. For him, its "just a ride".

 

[skibob]

Watched something on PBS about cholesterol versus inflammation, specifically as a result of carnitine (amino acid from red meats) being processed by gut bacteria and producing trimethylamine (googled that bit..). Byproduct, inflammatory response and atherosclerosis. So I'd avoid the red meats, don't beat yourself up on your cholesterol numbers, don't take statins, stop doing 15 mile runs 6 days out of 7 and do more yoga, moderate weights, moderate cardio.

It's funny, in the old days when you worked hard to eat, you wore out early and died young. Now we want to replicate beating ourselves up! Sitting on your ass isn't good..neither is 10 marathons a year, apparenly.

An important counter to this is that this may only pertain to muscle meats. Offal, and fatty cuts (brisket, leg of lamb, pork shoulder, etc) which also have a lot of connective tissue don't have the same issues. As we've moved from stewing the parts we can afford to filet mignon, we've lost a lot of what IS healthy about meat eating.

Add this to what @Bill Talbot said about WHAT the animal we are eating was eating, which really matters.

 

[skibob]

He mentioned red meat is looking really bad in terms of risk. He did however extol statins and says there's now good evidence they don't just prevent additional build up but also smooth out and reverse even when calcification has been in the mix.

I can only parrot back what this one doctor said, I have some research to do. I'd bet some of this stuff will stick, some won't but certain research has been peer reviewed and duplicated mid to long term and so may carry a little more weight.

Before taking statins, I would highly recommend somebody do independent and extensive research. There are lots of well-developed opposing thoughts. And, kind of like a lot of the depression drugs, what they do is mostly irreversible . . .

 

[Ron]

FWIW, the 28mm tires on my road bike, I run at 70R/65F and that is PLENTY for road riding. And I am ~200lbs. Of course, YMMV, but i would think you could go at least that low, if not lower if you are significantly lighter than me.

I've run my 25's (which seat up at 27.5) at 80 and found the RR to be noticeably higher than 95. yes, the ride is more harsh but the speed gained and lower RR on climbs is worth it. Now there's a happy medium there, i just need to find it. there's also truth that on climbs, vertical deflection is a net loss in inefficiency so again, you have to find what works best for the road conditions and rider. For instance, maintaining a steady, smooth cadence on climbs will help to mitigate vertical deflection to some degree

 

[Tom K.]

5 years ago 29'ers were going to rule the world..everyone had to have one and you were an idiot if you didn't. Now, not so much.

Things ebb and flow in the world of mtb preferences. 29er trailbikes were the single biggest resurgent category in sales this season. And EVERYBODY is rushing to produce a 130 - 150 mm 29er trailbike, if they don't already have one.

Since this has a great thread with a ton of good info, I thought I would include tire width efficiency into to the discussion. So it seems that going wider especially on our chip N' Seal, the 28's will of course be more comfortable but as efficient as a 25 if I reduce the pressure to 80-85 psi from my current 90-95.

For the geeky engineering types on the forum (that's me, raising my hand), this guy's site has some great data, which in some cases allows you to see what lower pressure with a 28 gives the exact same rolling resistance as a 25 or 23 at higher pressures:

http://www.bicyclerollingresistance.com/specials/conti-gp4000s-ii-23-25-28

You can also see on a smooth road that higher pressure is faster, but we sure don't get much of that around here.

 

[Ron]

29'rs are actually going to take another run at dominance with the new geometry that you will see in the 2017 frames. Essentially, 9'rs will have the similar geo's as 27.5's now with new Chain stays, BB heights, rake, and other factors enabling them to now how the benefits of much improved agility (the major complaint against 9'rs) coupled with fast climbers and smooth rolling. Suspension is now 130-140 where only a few years back, a 9'r would only have 100-110.

That's a great site! Yep, gotta find the right PSI for WHERE YOU ride, the site can't take that into account. its a good start though. Note he uses 100psi as the test PSI and the rolling resistance of course will be the same for all tires. He then shows the RR for 80psi with a 28 and in comparing a 25 with 100psi (a touch high) is almost the same RR. Cool stuff. - Note, that the conti requires a tube, I would argue that you might be able to run a higher PSI and get even higher efficiency with a tubeless setup like with a Pro One and still have the same comfort level as a tubed setup.

BTW- read up on the Schwalbe Pro Ones. He gives them a perfect score. BTW- I will never go back to a tubed tire. Tubeless is so much better.

http://www.bicyclerollingresistance.com/road-bike-reviews/schwalbe-pro-one-tubeless-2016