Tag: Tires

Bike tires and bike tire sizes for bike touring.

Categories
Bike Touring Tips

A Few Bike Touring Hacks

garbage bag bellows
The DIY air mattress bellows pump: light, cheap, effective and recyclable

D.I.Y. Garbage Bag Bellows Air Pump
The outdoor gear maker Big Agnes makes a combination stuff sack/sleeping pad pump called the Pumphouse. It sells for $19.95 on their website. A quick Google search reveals several videos detailing how to make one out of a plastic garbage bag, an empty plastic bottle and a garden hose rubber washer. Conveniently, the outside diameter of the input valve on many back packing and bikepacking sleeping pads is 5/8″ or so; the same as the inside diameter of a garden hose washer. So the rubber washer will just fit snugly when slipped over the valve. Here’s how to make the bellows:
– The plastic bottle cap to be used needs to have a diameter of around 1″. Drill a hole through the center of the bottle cap just a little bit larger than 5/8″. (drilling this hole is easier with the cap still on the bottle).
– Cut the neck of the bottle off just below the cap and below the little drip ridge on the bottle. Use sandpaper to clean up all the rough edges.
– Cut off a small corner of the garbage sack to make a golf ball sized hole.
– Take the lid off the short section of the bottle neck and poke the corner of the garbage bag with the hole in it up through the neck. Fold an inch or so of the bag down around the threads and screw the cap back on. Now the cap with the hole in it should slip over the valve on the sleeping pad and the rubber washer will create a decently air-tight seal.
– Open up the top of the bag to trap air inside it and quickly fold and twist the top together to make a big balloon. Then squeeze the air out and into the sleeping pad.
Besides being quite a bit easier than blowing up your pad by mouth, this system has the added advantage of not introducing a bunch of moisture into the pad, which reduces the thermal insulation properties.

A Visual (and relative) Way to Gauge Tire Pressure
Our camp the previous night was in national forest about a mile down an unpaved road. After rolling on the asphalt for about an hour in the morning we took a break and I noticed that there was a black stripe around our tires, contrasted against the dust left on the casing and sidewalls of the tires. These stripes defined the width of the contact patch between the asphalt and the tires as the tire deformed under the weight of bike and rider. The stripe on the rear tire of my bike appeared to be a little bit wider than the stripe on the front tire. For handling and tire wear I prefer to have roughly the same amount of deformation and resultant tire contact patch width on both tires. On a loaded bike with more weight on the back tire, that tire will need more air. I put a few pumps into the rear tire to equalize things a bit.

tire wear
Front tire contact patch. You can see the black stripe of the asphalt against the dust from the gravel road on the sidewalls
tire wear considerations
The contact patch of the rear tire as indicated by the black stripe is a little bit wider than that on the front tire.

Riding a Loaded Bike on a Long Descent
At the top of our first summit G. asked if I had any tips for descending at speed on a loaded bike. The only one I could think of was to gain speed slowly to see how the bike was going to handle. If there was any shimmy in the front wheel I suggested he move his hands to different positions on the bars and/or to move his butt on the saddle to redistribute his weight. No gyrations were required on his part however because his Soma Saga touring bike was designed for this type of use and was solid and predictable at all speeds. At the bottom I asked if he had any insights about descending now that he was a pro. He did say he felt like he had more control when riding with his hands on the brake hoods (he uses drop bars). Riding with the hands on the hoods also makes it easy to reach the brake levers quickly in an emergency. Some people recommend this position because the rider is able to sit up higher and create a little bit of a sail effect with the upper body to help scrub speed. And speaking of shimmy; if the bike feels unstable or squirrely at speed it could be a tire pressure issue. A few more PSI or a few less in the front or rear or both tires might cure it. On really long descents in high temperatures rim brakes can heat the wheel rims to the point where the tires will overheat and a blowout could result. This would be bad, but there is not much to be done except to be aware of the possibility and take it easy.

SPD Bottle Opener

pedal as bottle opener

Thanks for reading. Add your own bike touring hacks in the comments.

Categories
Fenders Touring Bike Tires

Tire and Fender Considerations for Snow and Mud

The temperature is going to be well below freezing this New Year’s Eve day and several inches of snow have fallen in the last 48 hours. A combination of de-icer, sand spread by the highway district and traffic has left the busiest roads mostly bare and dry. But driveways and side streets are covered with (one after another, or all at the same time) patches of snow, ice, slush and gravel. I’m not riding the bike today.

Ice on the street
Would even studded tires help here?

This morning I looked in a supplier’s catalog at tires with 400 or so carbide steel studs in the tread. I’m tempted to buy a pair but I’m not sure if even that would keep me upright on the ice. And the use for such tires is limited…I don’t really want to be taking them off and putting them back on every time it snows. If I had a bike with disc brakes I could try the old zip-tie snow chain trick.

Photo: Dutch Bike Co.

Earlier this month, before the snow was sticking, we went on a day trip from Three Horse Winery north of Eagle, ID to Montour, ID where we ate lunch before riding back. Scott and Aileen scouted this route prior and they were going to show us the fabled passage between Eagle and Montour which we had been unable to discover on our overnight trip last year. This turned into sort of an epic slog through mud and water and emphasized the importance of the right bike for the job… those of us with fenders spent quite a bit of time digging packed mud from between the tires and fenders. We even ended up taking Sky King’s front fender off when her front wheel completely bound up and stopped turning. For those on bikes without fenders and using disc brakes the going was relatively easier.

Here is a map of the route for those who might want to repeat it.

Even with the mud everybody had a great time and there was more smiling taking place than cursing although there was some of both. That is partly a testament to the cohesiveness and the great attitude of our fledgling bike touring group wherein everybody is quick to help others and nobody complains. Plus, every rider is competent and able to take care of themselves on and off the bike.

A touring bike continues to open my eyes to the scenic and solitary places within an hour or two of where we live. Places I never visited in the previous two decades of living here and probably would not have experienced in another 20 years, but which are suddenly accessible on my country bike. Not to mention a new group of friends….a group of thinking, entertaining and interesting people who make this hermit happy to be a part of it.

Categories
Touring Bike Tires

More About the Best Touring Tire

Schwalbe Marathon Dureme
The Schwalbe Marathon Dureme

I enjoy reading the posts and looking at the pictures on the Pondero blog. The latest post happens to be a review of the Schwalbe Marathon Dureme tire. Check it out and look at some of his other articles while you’re at it. Good stuff.

I copied the following from the Road Bike Rider website. While not normally a great source of information for the touring bicycler I think the question and the reply at least provide a starting point for a reasoned decision about tire selection.

Are 25mm Tires Better than 23mm Tires?
Question:

I found out yesterday from my LBS owner that I’m apparently late to the party moving up to 25mm tire width. I’m told all the pros have switched. Is this why I’ve been able to buy 700X23 tires on-line so reasonably? – Seth S.

Coach Fred Matheny Replies:

Yes, there has definitely been a move toward wider road tires, and I suspect that’s why shops and websites are putting 23s on sale.

A number of studies, most notably by Jan Heine in Bicycle Quarterly (www.bicyclequarterly.com), have shown that wider tires roll faster on all but the smoothest pavement if the tires have supple casings.

Wider tires also tend to be more comfortable because of the increased air volume and because they don’t have to be inflated as much to avoid pinch flats. They corner on bumpy pavement better because they don’t bounce around on the rough asphalt like narrow tires tend to do if they are inflated hard.

The weight difference between the same tire in a 23 and a 25 — or even 28 — is minimal. The extra few grams are more than compensated for by increased comfort and performance.

The only drawback is that many race-oriented frames won’t accept anything larger than a 25, or in some cases a 23. Manufacturers are remedying this, in large part because pro racers in events like Paris-Roubaix that features rough pavement and cobblestones are going to wider rubber. A good example of a carbon race-oriented bike that can handle a 28 is the Specialized Roubaix.

I’m a convert. I’m running Michelin Pro Race 25s (which are more like 28s) and Conti 4Season Grand Prix 28s on all my bikes except my old Litespeed Vortex, which will only handle 25s. I made the switch some years ago due to the extremely rough pavement here in western Colorado. We have a variety of chip seal, potholes, convex patches and grass-filled cracks, but while narrow tires beat me up, 28s smooth things out considerably.

I haven’t noticed any difference in speed — maybe a slight increase — but the added comfort is what sold me. I used the Conti 28s on the Pacific Crest Tour this summer and even on the relatively smooth pavement of Washington and Oregon, they made a significant difference in efficiency over the two-week event.

And while we’re at it the Schwalbe tire company has a page about tire size and rolling resistance. It’s interesting to note that, at a given pressure, a wider tire has less rolling resistance than a skinny tire. Obviously a skinny tire can be inflated to a higher pressure but the trade off is a less comfortable ride.
a rolling resistanc graph

So don’t just assume that replacing the tires on your mountain bike or touring bike with some skinny, punishing race tires will make your commute better. Might want to consider the construction and tread pattern too. Maybe a little wider tire will still allow you to punk the other commuters on your route and yet not beat you up before you even get to work!

Categories
Drivetrain Touring Bike Components

Schwalbe Marathon Mondial

(Update 2/20/2012 – The Bike Touring News store now has the Schwalbe Marathon Mondial tires in stock in 700 x 35c and 700 x 40c sizes in the folding version. The 26 x 2″ folding tire is due to hit North America in March,2012.)

Marathon Mondial 622
The new (2012) Schwalbe Marathon Mondial touring tire

The Schwalbe Marathon XR is frequently hailed as the best expedition/long lasting touring tire out there. The ‘XR’ was synonymous with ‘Schwalbe’, in fact, along with the regular Marathon, some think the XR helped build Schwalbe a good name and customer base. Unfortunately, in 2009 Schwalbe decided to discontinue the model. Other tires stepped in to fill the void, namely the Dureme and Extreme and the Plus Tour, but none of those had all the features that made the XR so popular.

Recently I read about a new tire- the Marathon Mondial. According to Sean at Schwalbe North America:
“……the Mondial is not a direct replacement to the Marathon XR, more of the next step in the evolution of the tire. Compared to the XR the Mondial will have the SnakeSkin sidewall which is an additional rubber coated aramid layer which helping to prevent sidewall cuts and abrasions. The Mondial also gets a modified triple rubber compound which we call TravelStar, the compound will increase road performance while also increasing the durability.”
For more information I went to the global Schwalbe website and found this about the TravelStar compound:
The Marathon Mondial has “State of the Art” TravelStar Triple Compound. Under the tread centre lies an elastic mixture for easy rolling, while there is a grippy rubber compound, for cornering traction on the tyre´s shoulder. In the middle of the tread an abrasion-resistant, harder compound offers low rolling resistance for thousands of miles.
Unpredictable gravel roads and potholes, acacia thorns: these are the treacherous tyre killers. Protection may come down to the smallest of margins such as the durability of the rubber mixture. The lightweight extremely densely woven High Density puncture protection belt reliably protects against punctures and ruptures. The light but sturdy “Snakeskin” protection provides maximum reinforcement against sharp objects that would otherwise cut the sidewall.

According to the catalog cuts I have seen, the folding version of this tire will have the TravelStar compound and the Snakeskin casing while the wire bead versions will have Schwalbe’s “Endurance” compound and their RaceGuard casing which is a double layer of nylon fabric.

Look for the folding tire in sizes 26×2, 26×2.15, 700×35 and 700×40. The wire bead tires will come in 26×2, 700×35 and 700×40 sizes. Availability in the US will be October 2011 for  limited sizes and 2012 for the complete lineup. Prices will range from $48.00 to $90.00 depending on size and version.

This thread at crazyguyonabike gets a little out of hand, but in a good, funny way.

 

Categories
Drivetrain Touring Bike Components

Tire Sizes – Actual vs. Nominal

I had a question from a customer about actual widths for some models of the Schwalbe Marathon tires we carry. He is concerned about getting tires that will fit without rubbing on his fenders. I figure others probably have the same questions, so I have compiled a chart showing the actual measurements of some of the tires we carry. I will be updating and adding to the list. If there is a tire you want to know about, and it is not shown, just post it on the comments and I will try to provide actual dimensions for you.

I was going to go into some detail about tire sizing nomenclature but, as usual, the late great Sheldon Brown does a better job than anybody else could. So if you are unsure about what the size markings on your tires mean, check out Sheldon’s page.

All tires will be marked or stamped with the size. 700c and 28″ are two different nomenclatures for the same diameter.

As can be seen a 700c or 28" tire is actually neither. The numbers refer to the diameter of the tire when mounted on a rim and inflated.
The ISO/ERTRO measurement is the first pair of numbers

The ISO/ERTRO number is the most important in determining if a tire will fit on a particular rim. The second number in the pair is the diameter of the rim measured where the tire bead will seat.

This tire has a 622 ERTRO diameter and will fit on any rim with the same diameter measured to the points where the tire bead seats.

So called 29’r tires fit on rims with an ERTRO diameter of 622, but generally have a more voluminous casing so the overall diameter and widths will be greater.

So on to the Tire Width Chart. I measured the width of the inflated tire with a pair of calipers. The “height” is measured from the outer edge of the rim to the road contact surface of the inflated tire.

Measuring width
The "height" measurement
Chart shows nominal vs actual tire sizes.
Schwalbe Tire Width Chart
Categories
Bike Touring Tips Hermit's Workshop Saddlebags

@#!% Flat Tire

There are dozens of videos out there about changing a flat tire. None with background music by Sonny Stitt.  Here’s one!

A couple of things. Notice that I just lay the bike on it’s side with the derailleur up. That’s an easy way to do it when you’re on the side of the road. Also, I shift the chain into the smallest cog. When I put the tire back on it’s easy to remember what cog to put the chain over so that the wheel will be centered.

This is what I carry on the bike to change a flat:

Pump. I use a Zefal HPX frame fit pump. This pump is all aluminum and the barrel is long enough to push a decent amount of air, so the tire is up to pressure relatively quickly. Plus, unlike CO2 pumps,  it has never failed or frozen. It mounts to the underside of the top tube

on  bikes that have a pump peg.

Or it can be mounted in front of the seat tube, but this precludes the use of a water bottle there.

Spare tube, tire levers and patch kit. The simplest and quickest way to fix a flat is to change the tube. But I only want to carry one spare and if I get another flat I need to be able to patch one of the flat tubes.

Seat bag. For shorter day rides I use a Zimbale leather saddle bag to carry these items plus a multi tool.

Categories
Touring Bicycles

Steel Bikes And Comfort

Even though I’m a fan of steel bikes, it’s mostly because of the durability of the material. I certainly like the ride quality too, but I think the idea that steel is a more plush or forgiving ride because it flexes or dampens is hogwash. The idea has almost become gospel now just because it’s been repeated so many times.  Don’t get me wrong, I know my steel bike frames flex…. I can hear my fender and/or brake and/or front derailleur rub from time to time if they are a little out of whack and I am pressing hard on the pedals. But that is torsional flex.

It’s the idea of vertical flex of a bicycle frame I have a hard time envisioning.

Scientific diagram

Imagine the arrows to be balancing the downward force of the rider and the bike.

Continue reading “Steel Bikes And Comfort”
Categories
Drivetrain Touring Bike Components

Bicycle Touring Tires

This is literally where the rubber meets the road. It’s sort of a boring topic but tire problems could end a bicycle tour quicker than almost anything I can think of. And a flat tire is probably the most likely mechanical repair a traveling bicycler will need to master. Luckily, there are many very good options when it comes to bicycle touring tires.
There is a wealth of information stamped on the side of a bicycle tire.  Here you will see the size of the tire. For example 700 X 32 for a 700c diameter tire or 26 X 1.75 for a 26 inch diameter tire.   The second number, after the “X”,  is an indication of the width of the inflated tire. Depending on your bike, you may either have 26 inch wheels or 700c wheels ( there are other sizes of wheels, such as 650b or 27 inch, but those are not as common)
You will want to carry one or two extra tires with you depending on how far it is between bike shops on your route. So make sure you know what size your bike takes. Most tires come in a “folding” version, which means the bead, or the part of the tire that hooks on the rim, is made of flexible material and the tire can be folded or rolled into a small package.

The width of your tires will affect rolling resistance, comfort and durability.
It may be counter-intuitive but for a given inflation pressure a wider tire will have lower rolling resistance than a narrower tire. And lower inflation pressure, to a point, means a silkier ride because of the greater air volume acting as a cushion.
A wider tire with more air volume will also help protect against pinch flats- the pinching of the inner tube between the tire and the wheel rim when hitting a sharp bump.

Tires with a smooth tread, even no tread, will work best for rides which will be mostly on paved surfaces. Bike tires behave differently than automobile tires and grooves in the tread of a bike tire do nothing to increase grip. In fact, the more rubber actually touching the road, the better. The tire maker Schwalbe explains this better than I can. If you’re riding off-road or on un-paved roads a knobby tread pattern is more important.

zion bike trip
note the 650B makes a great touring tire

Look for tires made specifically for touring or urban riding. These tires will have layers of  puncture resistant materials such as Kevlar or Aramid under the tread. Usually the casing of these tires will be strong enough to handle the extra weight and loads of a touring bicycle. Sometimes the rubber tread itself will be significantly thicker than the tread on a racing or training tire.

I have used the Panaracer brand T-Serv tire for my tours the last two years and I have been very happy with the performance. These are not super burly tires but I am not heavy and I travel relatively light. The tread wears very well on these tires and the Aramid belt works well to prevent punctures. The cord used in the casing is strong, but the tire is still supple and feels smooth to ride.

Schwalbe Marathon is a line of tires which includes tires made for bike touring.  Everything from tires for light touring to tires made for the extreme expedition adventure.

Don’t scrimp when it comes to buying tires. You will have enough things to worry about and enough challenges to keep you busy on your tour.