[Someone]

FTA: Can we verify the folklore that on a long bike trip the back-tire wear is less than that of the front tire?

I’ve never heard that folklore. I thought ‘everybody’ knew back-tires wear out a lot faster because the load on them is higher and because they’re the one being powered. https://www.sheldonbrown.com/tire-rotation.html:

“It is common for a front tire to outlast a rear tire by as much as three to one. Rear tires have more weight on them, and also have to deal with drive forces.”

[Moru]

It depends on how you use the bike. When I was a kid I used to turn the front wheel left/right to go forward instead of using the pedals. This ofcourse wore out the front tire realy fast :-)

[fluoridation]

How does that work? I don't see any way that just turning the bars would imprint forward momentum.

[matsemann]

By "pumping" it's quite easy: https://www.youtube.com/watch?v=5tVlAlZ9wfM

You can to some extent do it without that much motion as well. Basically, you're "falling" to one side and getting momentum, and then you "save" the fall by twisting back getting the bike under you, and that instead puts the momentum forward.

[anthomtb]

I would like to add that you are not just "turning the handlebars" - you need to apply a lot of force to get the forward action to take place.

Pumping is fun skill, easy to get the hang of with a little dedicated practice, and a prerequisite for BMX racing or any advanced MTB riding. Its also extremely inefficient for forward motion. You don't see any TDF guys using pump motion unless they're saving a crash.

[Moru]

It was 40 years ago, what I remember it works but not very good. As they say lower down, you need more movement to actually get any sort of speed forward. It was just something I liked doing while waiting for someone to show up.

[leoedin]

Yeah - that just seemed completely wrong based on my experience. I've commuted by bike for years, and my back tyre is always the first to go.

[matsemann]

Same. Also same on my road bike, which I bike in a very different manner (not as much stop&go, short turns etc). And I even do most of my breaking using the lever connected to the front tire.

[navane]

From my experience, front tires only wear of age, not use. Backtires experience (frictional) shear forces, pushing along the earth. This erodes the surface.

[c0nsumer]

Cornering and braking does wear the front tire, and it is more notable when mountain biking where cornering tends to be more forceful and the tire knobs concentrate forces on more noticeable parts of the tire.

[michaelteter]

And from those glorious big fishtailing skids we do as kids...

[giraffe_lady]

never stopped being fun this is why fixed gears are still a thriving niche

[convolvatron]

I picked up riding again after .. 40 years and a car braked in front of me and I did a perfect skid stop without even thinking. we are really amazing things.

[OffensiveIdiom]

This has been my experience as well. The back tire gets worn down and the front tire lasts until the rubber starts cracking from age.

[InCityDreams]

At €70 a pop, my tyres get rotated front to back, as required. Back wears out much faster.

[adrianN]

70€ for 15k kilometers or so is really cheap. It's incredible how cheap cycling is per kilometer. At least an order of magnitude cheaper than driving.

[wiredfool]

15K is an overestimate for most bike tires. It might be accurate for ultra hard commuter ones, but my experience is more like 2k miles for a rear (at 700x25c, single racing bike) and 5k for the front. At that point, the rear is a pretty square shape, with thin tread in the center, and starts to have some interesting handling issues.

Wider, more supple tires might do better than that, the 26x2.2 rear on my tandem is 2k miles in, and probably has another 50% of its life left. Tandems are kind of noted for eating tires due to the loads on them.

[ljf]

I was about to agree then I did my own maths.

I used to use GatorSkins - as they are perfect for London cycling. I used to commute 29 miles a day, 5 days a week, plus complete a 60ish mile ride on weekends - so times that by 47 weeks (5 weeks leave where I wasn't commuting) gives 9,635 miles. My gatorskins easily lasted a year, usually more - in fact I still have one of my London tires on my good bike, 7 years later (as the front tire) (I no longer cycle commute and only ride for leisure now.)

So I think those miles really are possible on a good tire. I used to use cheapo tires but ended up changing them 3 or 4 times a year and burning through inner-tubes.

[_Wintermute]

2k miles is only 2 months for someone doing decent mileage, but even pros don't train on thin racing tyres.

[wiredfool]

The 2k figure was from a Michelin lithion 2, which was a decent for the price cheap (15 eur) 700x25 tire. It’s not an event tire. Mainly chosen for its relatively price and predictable performance (1 compound).

The tandem and wider tires are not the cheap ones though, they’re Rene Hearse, roughly 90eur or so. I’d say they’re worth it, but they are about the same price as my last car tires.

[adrianN]

My Schwalbe Marathon Plus last around 20k. That's about five years for me.

[uoaei]

And if you can do your own maintenance, and buy used frames and parts, you can probably say 2 OoM difference. You'd spend more on the calories that fuel your commute than on the bike and accessories.

[faeyanpiraat]

I've just done a back-of-the-envelope calculation about fuel costs, and the extra food you have to eat if you are cycling vs the fuel cost for the car for the same distance is in the same ballpark.

So if we also assume that during the lifetime of the vehicle the cost of fuel you'll burn will be in the same ballpark as the cost of the vehicle, then the total cost of riding the bike will only be around 50% of using a car.

[matsemann]

How are you calculating that?

Normally, one assume about 24% efficiency in human pedaling, so that 1kJ of energy going forward = 1 kcal consumed.

Now, fuel cost is anyways a small part of owning a car. My 1k bike + food has lasted me years, while that's less than a newer car loses in value each month.

[newaccount74]

https://biketips.com/calories-burned-biking/ says I burn ~600kcal to ride 20km.

600kcal is ~200g of bread + 20g of butter. Bread costs about 5€/kg, butter costs 2€ / 250g so 600kcal is roughly 1,25€.

My car uses about 6l gasoline per 100km, current price is ~1,60€ per liter, so 20km need 1,90€ of gasoline.

So if I just eat cheap food riding a bike is cheaper.

If I eat at McDonalds, then 600kcal is a hamburger with medium fries, which costs ~4,50€. Then taking the car is cheaper.

This is quite surprising!

[uoaei]

The costs of sitting idly every time you travel, compared to doing some low-impact cardio over the same distance, for trips shorter than about 3 miles, definitely adds up over the years.

The results looks absurd because the math is ignoring a lot of real-world considerations.

[uxp100]

I think bicycle calorie burn calculators are basically just nonsense. 600 calories is a ton to burn for a relatively short leisurely ride. Maybe 5x too much.

I have an older garmin that has told me I have burned 9000 calories in a weekend, and uh, I didn’t. No evidence for that, but I simply don’t believe it. Bicycle tourists would have to have wild food intake to sustain that for weeks.

[matsemann]

What if the added calorie need comes from rapeseed oil or something really cheap? :D

But I think there's some factors at play here. One is that if I didn't commute to work, I would have to work out some other way to get my daily movement in. So it's not necessarily that I eat more just to bike. I just use that energy to move myself to work instead of on a treadmill going no where.

Another interesting factor is what about electrical bikes? The amount of kWh needed to move a small person vs multiple tonnes of car should make it a huge win.

[woodruffw]

If we do this kind of calculus, it’s probably worth including the expected health costs of not exercising. Especially if your normal meal is a hamburger at McDonalds :-)

[johannes1234321]

Even when just sitting around your body requires energy.

[adrianN]

2000kcal of noodles costs like one Euro and fuels you for like five hours of cycling, 100km open road maybe. An average car burns 7l or 12€ of gas. But if you're concerned about calories, just buy an ebike.

[pharmakom]

You should still need to exercise if you drive.

[fluoridation]

You're not actually saving anything in the long term, though.

Let's say you start with brand new tires on both wheels. Let's further suppose that you completely wear out your rear tire in 1 year and your front tire in 4 years. If on the first anniversary you rotate and place the new tire in front, you'll need to repeat the procedure after 9 months, and then every 9 months after that. On the 4th anniversary you'll have bought 5 tires: on the 12th, 21st, 30th, 39th, and 48th months. If you simply replace each tire as it wears out without any rotation, on the 4th year you'll have bought 5 tires, 1 to replace the front tire once and 4 to replace the rear tire 4 times.

[matsemann]

True. What you do have is a more consistent / good front tire, which is important for handling curves in wet weather. So still worth doing, instead of riding with a front tire on its last 20% of life.

[fluoridation]

IME as long as the tire is not flat there's no difference in handling between a new and a worn front tire, at least on asphalt.

[relwin]

Road tires wear unevenly on the sides due to crowned streets. You should also flip rotating direction, assuming unidirectional tires.

[newsclues]

Rear tires do must of your braking. If you hit the front break too hard/fast, you flip over the front tire, hit the rear brake hard/fast and you burn rubber/lose traction.

[lonelygirl15a]

As a bicyclist, I use my front brake vastly more than the rear.

https://www.sheldonbrown.com/brakturn.html

[doubled112]

I don't even have a rear brake.

Weight is transferred to the front on heavy braking, and if you have proper technique, you will not go over the bars. The front tire does all of the actual stopping.

[snozolli]

The rear brake is very important for initial braking, in order to transfer weight to the front, which allows harder braking without locking up the front tire.

When you initially hit the brakes, your braking potential is split around 50:50. At absolute maximum potential braking force, your rear tire is near lifting, so it's around 100:0.

That said, if you only have one brake, it's better to have it on the front than the rear.

[JohnFen]

Interesting. I have to replace the shoes on my rear brakes about 10 times more often than my front brakes.

But then, if I'm not going very fast, I only use my rear brake. That might explain it.

[snozolli]

I have to replace the shoes on my rear brakes about 10 times more often than my front brakes.

That just means that you brake with your rear the most. I'm talking about maximizing braking potential.

I've been riding motorcycles for decades and it's drilled into you to practice panic stops regularly, which habituates the transition from 50:50 braking to 90+% front brake. I don't think many cyclists do this exercise, but they'd probably benefit from it.

[jackvalentine]

Do you ‘ride the brake’ to control your speed a lot?

[pharmakom]

Agree that front brake is more important.

However, I like to have both (and suggest you do too!) because:

1. Brakes can fail

2. In slippery and inconsistent conditions, locking up the rear is preferable to the front

[newsclues]

If you don't have a rear brake, perhaps listen to people who have front and rear brakes, and thousands of kilometres of riding.

I have literally seen people flip over their handle bars by solely using their front brake going downhill.

[doubled112]

I have done thousands of KMs of riding.

[newsclues]

Cool, I've done thousands in a month. Do thousands every year.

But if your bike doesn't have two brakes as you have stated, it doesn't matter how many KMs you ride, because you are not getting that experience to inform you.

[jackvalentine]

I’ll back him up - I do thousands of kilometres a month and log component changes when they happen!

My rear brake pads last about 5000km before they need a change, my front brake pads last about 3500km.

It would appear by observation of the consumables that the front brakes do the most work. This is in-line with my expectations from the experience riding the bike and established knowledge about how weight transfer works in vehicle braking - there is a reason cars always have bigger discs on the front and some cheap hatches still have drums on the rear.