Bike Tires & Pressure

This is reference info for me:

  • Pavement Reference: 700c, 28mm @ 120psi for 300 LB ride weight, 60% rear
  • Cruiser Reference: 32er, 55mm @ 60psi for 310 LB ride weight, 70% rear
  • Off-Road Reference: 700c, 40mm @ 40psi for 180 LB ride weight, 60% rear

Slower speed, butt off the seat, you can go lower psi. You’d be risking pinch flats on longer rides, or unseating the bead in harder turns, etc

Tread pattern is coarse for rough terrain, fine for sand & hardpack, and smooth for pavement.

Higher pressure prevents tire flex, and is better on pavement. – Less shock absorption, grippy on soft, loose surface.

Lower pressure increases tire flex, which grips obstacles better. – Increased risk of pinch flats, or rolling off the rim.

General width preferences:

  • Hardpack or pavement – narrow to prevent drag
  • Sand, pea gravel, mud – wide to prevent sinking
  • loose, large gravel – wide to prevent pinch flats, throwing gravel, etc

Weight Distribution

  • Cruiser ~ 70% rear.
  • Mountain ~ 60% rear.
  • Race Road ~ 55% rear.

Proportional adjustments:

  • Narrower tire for larger diameter
  • Lower pressure for lower weight
  • Lower pressure for wider tire

Rim sizes:

  • 559mm = 26er
  • 584mm = 650b / 27.5″
  • 622mm = 700c / 29er
  • 686mm = 32er
  • 787mm = 36er

Calories per Mile

This is a SWAG for calories burned cycling 12-15mph:

* Divide your feet climbed by 10.
* Divide again by your average MPH.
* Add that to your total miles.
* Multiply the new number by the weight in pounds of you, your bike, and everything you’re carrying.
* Multiply the new number by 0.105 (or divide by 9.5).
* (Use 0.115 or 8.7 if you only know your own naked wake-up weight.)
* That is pretty close to your calories burned for the ride.
* Baseline here is me, 6’5″, anywhere between 250 and 290 pounds plus bike weight (any bike).

BMR is not a part of this SWAG:

* BMR is how much you burn in 24 hours of sleeping.
* Most people are around 9kcal per pound per day.
* BMR and is not based on your activity level (see TDEE).
* BMR is based in your microcellular efficiency, and is influenced by hormones.
* If you are on severe caloric restriction, it goes down.
* Thyroid issues can affect this either way.
* Baseline here is me, at 285 pounds, and averaging 2550 kcal per day.

Faster speeds pick up exponentially more wind resistance.

* Twice the airspeed has four times the wind drag.
* Higher density altitude has proportionally less drag.
* Shorter and narrower shouldered people people have less wind drag.
* Fatter people are slightly more aerodynamic, so the increased wind profile is not THAT much of an issue.
* Cycling 10mph into a 5mph headwind has as much wind drag as cycling 20mph with a 5mph tailwind.
* 12-16mph is the 50% transition for wind vs other factors on flat ground. (13mph for me at 6 sqft)
* Baseline here is me, with about 6 square feet of frontal area, about 22 Watts at 10mph, and about 150 Watts at 20mph, just for wind.

Rolling resistance is a big part of drag.

* Increases linearly with speed (2x speed is 2x the rolling drag).
* Lower weight is better (because tiny bumps have to push you UP over them).
* Race tires can be half the CRR of average tires.
* Wider tires are better by around 1% per mm with 23mm as baseline.
* Baseline is me, at 310 total, 31W at 10mph, or 61W at 20mph on 1% grade.

Routes with less uphill than downhill will cost fewer calories.

* Increases linearly with speed (2x speed is 2x the gravity drag).
* 1% uphill is 2x the drag of rolling resistance. 2% is 4x.
* Lower weight people do way better on both gravity and CRR.
* Baseline is me, at 310 total, 62W at 10mph vs 124W at 20mph on 1% grade.

Good links:

* https://www.gribble.org/cycling/power_v_speed.html
* http://mccraw.co.uk/wind-resistance-cycling-speed/
* http://mccraw.co.uk/optimising-for-long-distance-speed/


Cycling Fuel

Max bodyfat you can burn in an hour is roughly 1 gram per 10 pounds, or in calories, 9 times your weight in pounds.

Anything else is food, muscle glycogen, or actual muscle tissue. Glycogen max is about 4% lean muscle mass, which usually is enough for 90 mins, plus or minus. Food is whatever is in your gut, though exercise slows digestion.

Bonk is when you have used up all food, and your glycogen stores, effectively exercising while fasted.

Bonk power is the max sustained energy ouput when you are fasted/bonked. This is fat burn, and muscle breakdown, combines.

Average watts is roughly 1/4 your calories per hour.

Me as an example
I’m 280 pounds, and bonk power for me is 133 watts, which is about 520 calories per hour. Doing that pretty much guarantees cramps from muscle breakdown.

Biking, I tend to burn 750-850 calories per hour, but I can peak at over 1000 in some instances (beginning, well fed, well rested, very driven).

That’s a big gap, because being big, I get more wind drag, which is 50% of your energy above 15mph. I also take more energy to climb a hill.

Downhill is faster, so less benefit (less time spent going downhill), and often waste the energy by riding brakes so as to not plow through others.

I do best consuming 600 calories per hour while riding more than 90 mins.

So, I have to eat the equivalent of a meal every hour to keep up, and reduce cramp risks. Most of that needs to be carbs that break down in less than an hour. Also, I don’t want to have a bathroom break every hour.

Ride Fuel
Sugary colas have phosphate, glucose, and fructose – all good for refueling. Cookies, sandwiches, etc usually are low roughage, good energy density, and include salt. M&Ms were actually designed to be endurance fuel for the army, and they hold up pretty well in a plastic bag.

Basically, all the things that are bad for you normally make great endurance fuel.

As to proper “race fuel”, honestly, it’s too low calorie for someone my size. Some people only need 200 calories an hour to stay fueled, so half banana, a 2″ square of granola, and a swig of gatorade is fine. For me, that would be a whole bunch bananas, and two quarts of gatorade. Just too much bulk.

Impediments
Add to all that the need for oxygen to build ATP (actual muscle energy chemical). It takes 35% more oxygen to burn blood glucose than intra-muscular glycogen. Fat takes twice as much oxygen as glucose. High heat, humidity, low pressure, altitude, carbonation, and alcohol all reduce oxygen availability. Transport of glucose into the cell takes ATP. Digestion of food takes ATP.

Diabetes, Insulin Resistance, and Metabolic Syndrome
The key there is to not eat much carbohydrate outside of the exercise times. When glycogen reserves are full (muscles recovered), and adipose cells are replete, then why would you need more fuel? That’s the practical wording of the physiology here, despite the perception of a faulty hunger mechanism for the obese, or lack of islets for type I, or the defective signalling in Type II without obesity triggers.

Exercise induced glucose uptake is normal in diabetic muscle cells:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4315445/
https://www.ncbi.nlm.nih.gov/pubmed/3899806
http://www.medscape.org/viewarticle/438374

Exercise may increase glucose sensitivity:
https://www.ncbi.nlm.nih.gov/pubmed/3899806

While glycogen is being replenished, glucose uptake by muscles in normal. GLUT4 is transported to the membrane during exercise, even in absence of insulin.
http://diabetes.diabetesjournals.org/content/62/2/572
http://physiologyonline.physiology.org/content/20/4/260.full
http://www.sciencedirect.com/science/article/pii/S1550413107000678


Bicycle cross-chaining

Mark loves to prod me about cross-chaining, because it’s formally a naughty-no-no. I thought I’d give some observations, since I am a chronic cross-chainer.

Cross chaining wears the sides of the sprockets, which is never what wears out. I ride like I am a 1×9 unless I’m on hills. No problems. All major makers support 1×11 (single gear in front, all the way back and forth in the rear).

Cross chaining puts a side load on chain pins, so use a chain whose plates don’t pop off. Most are made by KMC, with a brand label on them. I found SRAM branded chains hold up better. SRAM was the first to offer 1×11 drivetrains. KMC branded, Shimano branded, etc would pop a link by 600 miles. Maybe better now, but I have no reason to change brands. Bell chains are just too heavy/slow/frictiony, but work fine. Whippermsn chains are super durable, but expensive. Chains with a dimple or flat pin edge are better than the ones that look like a wite cutter went after them.

Wear on the teeth, ramps, and pins of the cassette/chainrings is due to shifting. Side loads don’t matter much, but heavy loads do. Don’t shift under high load, and they will last longer. If you hear a crunch when shifting because you waited to downshift, that’s more damaging.

Wear on chains is mostly from higher wattage, incorrect lubrication, and grit abrasion. Clean and lube your chain any time you can hear it at all. Try different lubes and see what you like. You can even throw it in a jug of 50wt motor oil, or molten candle wax if you like, but make sure to wipe it off well. Oil only needs to be inside the rollers. Anywhere else attracts grit.

Wattage, well, whatever power you can put into a chain is part of the fun, but if you are 285 pounds like me, and stand to power up a hill, expect more wear.

Lastly, when your chain gets to 0.5% stretched, replace it. Letting it go longer causes additional wear on the sprockets.

The only other issue to bring up is practical, not wear related, and that’s dropped chains.

If you are all the way tiny in the back, and shift up to the big ring in the front, expect to drop the chain off the outside, onto the crank arm.

If you are all the way small in the back, and try to shift to the small ring up front, expect to drop your chain between the cranks and the frame.

If you are fast, you can soft pedal, shift 2-3x in the rear, then shift up front, before losing much momentum. Chain guards and idler arms are not super effective at preventing drops caused by cross chaining.


Bicycle Tire Pressure

Optimal tire size and pressure isn’t always known. Here is a great calculator I use when I set up bikes.

The “Bike + Rider” weight is usually about 10% over your out-of-the-shower weight, and includes your clothes, tool bag, bottles, bike, etc.

The middle calculator automatically shows front and rear tires separately. I recommend that.

For tire sizes, you can pick what you have installed, and see what’s the best pressure for front and rear.

I like to run 2 different sized tires so I can keep the same pressure front and back, but due to frame limits, my rear tire is still too narrow.

If ideal for a road bike is under 80psi, (light riders), then you might consider going with a thinner tire. You’ll find it easier to spin up.

If ideal is over 120psi, you might consider a wider tire, because higher pressures can be harder on rims, tire casings, etc.

If you’re riding dirt, then lower pressures are better, to a point. Under 30psi usually means rock crawling, low speeds, and a tubeless setup. Over 80psi usually means you’ll have traction issues on softer surfaces.

Also. this person’s domain is “Dorky Pants R US”, which is just really great fun.

http://www.dorkypantsr.us/bike-tire-pressure-calculator.html


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Disable Strava Live Segments on Garmin

Garmin support says to disable individual segments on your device. Well, new segments show up still, and things get re-enabled. When Segments are enabled, it chews up more battery, just like following a course. Also, Garmin support takes DAYS to respond, and seems to send you to a level zero support queue first.

Strava support was awesome. I got a simple, exact response in three hours. To disable live segments, go to garmin connect. From the hamburger menu in the top left, click the arrow next to segments (way down in the list). Click the button to add it to your dashboard. Now, you’ll see the widget on your dashboard. From there, click the gear on the widget. Choose “Use Garmin Segments”. BLAM! You’re back to not using Strava Live Segments. You can toggle it on and off there, even though the initial enablement is on Strava’s webpage.

I wanted this disabled, because every time I would go near a segment, it would beep at me a few times. If I crossed over the start of a segment, it would beep no less than 15 times before it gave up. This is from an Edge 520 on version 7 code. Maybe it’ll be better in the future, but it’s just a distraction to me. YMMV


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Spinal Health

My critical stretches are:
* Calf stretch just because it reduces referred pain on hamstring stretches, and because I tore a gastroc once.
* Hammies get a hurdler stretch or similar. Tight hammies are big, bad back things, and a major problem for me.
* IT bands get a figure-four, or a leg over stretch to help reduce piriformis syndrome.

Others I enjoy when remembered:
* Pidgeon pose gets adductors AND IT bands a little, because I cannot really do the splits. This is mostly for 2 days after a long bike ride.
* Quad stretch, usually just grab my foot behind me and get as much stretch as I can. This is more for my knees than anything.

Core strength I need more of:
* Planks in all 4 directions also help core. Front plank can be replaced with pushups if form is good. Modified planks/pushups as necessary to prevent strain.
* Rows, whether off a doorframe, or a table, or with proper equipment, are important. However, a year post-op, and I’m still not really comfortable with twisting under load. I do one arm at a time, and keep my shoulders square. YMMV.
* Walking / hiking are great for core if it’s more than a few minutes, and more than just on a track or treadmill.

Aerobic/Calorie Burn
* Road bikes are low impact, but the bending is not always best.
* Spin bikes are easy to sit upright and get comfy, while burning calories, but the class matters a bunch.
* Some people run, but if your heel hits the ground, it just hammers your spine.
* Swimming, if that’s your thing. More of an upper-body thing.
* NOTE: Stretching after a good warm-up will be much more effective. Also, a good warm-up will break down some of the tight strands the same as stretching, just smaller amounts per step/stroke/whatever. Also, if I don’t stretch after a long bike ride, everything goes bad faster.

Other Stuff
* There are other body stretches I should do, but I don’t suffer when I don’t do them. The /r/bodyweightfiness has good enough reference that I mostly ditched all of the other lists, charts, and PT printouts for it. http://www.reddit.com/r/bodyweightfitness/wiki/kb/recommended_routine.compact
* Aspirin for NSAID since my family has a history of clots, and Ibuprofen/Naproxen increase clot risks when used long-term.
* Hot Tubs/showers are awesome for relaxing muscles, preventing cramps, etc.
* Extra salt when I exercise, because I’m a salty guy. Seriously. I cramp up if I don’t get enough, and this could be 1-2 grams of salt per liter of water consumed, depending on the temperature outside.


HEATMAPS!

I updated my GPS heatmap on Strava. They only do for Cycling OR Running, but nothing else, nor a combined map. *sigh*

So, my walks that had GPS were converted to runs. Some had a little running. It zooms way out, because most of it was in the Bahamas, but there’s a little blob on the trail behind my house. I also have non-GPS chunks at a couple campsites, and in Argyle, but they’re not on any maps.

Anyway, here they are:
Cycling: http://www.strava.com/athletes/2411233/heatmaps/755521fe

Running: http://www.strava.com/athletes/2411233/heatmaps/58a361f3


Sanger Chase Ride

Ride to Sanger with the Sharon group. I was 22 mins late leaving the house, so I told them not to delay the start time. They waited 5-6 mins for me at Hwy 377 and Bonnie Brae. It was a hard push to catch up, and Sharon pushed hard once I got in sight.

Unfortunately, this sort of punished/burned out some of the others as well, especially Jim F. Jim tried to hang on, but at the end he finally admitted he needed to work his way up to this length of ride. He completed it, but with our waiting, it was 2-3 hours extra. That being said, for being about 3 months post-op for hip replacement, he’s doing awesome.

Becky took the SAG wagon back from lunch because of other committments.  Karl took it because he broke a drive-side spoke in the middle where it’d been notched by the chain about 2000 miles ago.

http://www.strava.com/activities/190791492
http://connect.garmin.com/modern/activity/584287752

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