Rene Herse 11-speed Chainrings in New Sizes

Chainrings choice. It’s one of the main attractions of our Rene Herse cranks – together with light weight, supreme reliability and, dare we say it, good looks. So when we presented our first 11-speed chainrings, it was only a matter of time until the program was expanded. Now we are introducing our 42/26 and 44/28 chainrings, which complement the 46/30 rings already available in our program.

More than two years ago, we asked our chainring suppliers about 11-speed chainrings with shifting aids. Their answer was: “No problem. We can machine generic ramps into your rings and rivet in a few pins, too. We do that for many companies.”

But that was not what we had in mind: We didn’t want ramps and pins that are more cosmetic than functional, and don’t really help with shifting. As with all our parts, we wanted our 11-speed chainrings to equal the performance of the best in the business.

That was the start of our most ambitious R&D project to date. Since that first conversation, it has taken more than 2 years, hundreds of engineering hours, dozens of computer models, and thousands of testing miles.

As always, our first step was to research what others had done. It soon became obvious that only the very largest component makers have developed well-shifting ramps and pins. Understanding their thinking allowed us to come up with improvements and modifications that would make our rings work at least as well as theirs, while preserving the shape and interchangeability of our Rene Herse rings.

After we had developed our new chainrings in concept, we printed models on our 3D printer. These rings weren’t strong enough for riding, but they allowed us to visualize how our ideas work in practice.

Then came the big step: Commissioning prototype chainrings – easily recognizable by their unpolished surface. The complex shape of the teeth requires a 5-axis CNC machine, so we can’t make them in-house. As one-offs, they are very expensive, so we had to be sure of our design before we ordered them. Fortunately, they worked as well as we had predicted. I rode them for a few thousand kilometers last year, including in the Volcano High Pass Challenge and at the Bicycle Quarterly Un-Meeting. I’m happy to report that they really do perform as well as the best rings you can get from the big makers.

After we introduced the 46/30 rings, we continued developing the other sizes. Each ring is a separate project, and each ring is designed to work only with a single inner ring: The teeth of both rings must line up in a particular way to get a good shift. The pin must hit the chain in the middle of a link and not at the pivot, otherwise, it doesn’t really do much to lift the chain. And then the chain must mesh seamlessly with the teeth of the big ring. That part is actually the hardest. Most makers look at the problem from a static point of view, but to optimize the shifting, you need to consider that the chainring is spinning at 90-120 rpm. The downshifts require other parts of the chainrings to be relieved, so the chain can pass to the inside without having to climb over the teeth first. There is a lot to it, and much of it is a trade secret.

What happens if you use the new rings with different inner rings? Nothing bad, it’s just that the upshifts aren’t much better than without ramps and pins. During downshifts, you’ll still benefit from the optimized tooth profiles that allow the chain to move smoothly off the big ring. (With downshifts, the chain always lands on the small ring, so it’s not important to have a matched pair of chainrings.)

I’ve been testing the new sizes over the summer on some epic rides. I’ve really appreciated the smallest combo, the 42/26 during a solstice ride around Mount Hood in Oregon. I ride it like a 1×11 most of the time, but with smaller steps between the gears. And when I need a really small gear, I shift to the granny.

Natsuko really likes the 44/28 combination, and she can’t wait to try the new rings on her C. S. Hirose. The 46/30 is perfect for fast road riding. I use that combination on my randonneur bike. We are excited to offer all these sizes with 11-speed compatible, smooth-shifting chainrings.

The new chainrings work equally well with 10- and 9-speed. They are designed to work with all shifting systems – STI, Ergopower, DualTap, but also bar-end and downtube shifters. There is only one thing to keep in mind: They are designed to work with Shimano’s Ultegra chain. The pins have to be designed with a specific chain in mind, and we found that the Shimano Ultegra chain works best. Use the Ultegra chain that is appropriate for the number of cogs you run, and you’ll enjoy the fastest, smoothest shifting you’ve ever experienced on a bike – while running chainring combinations that perfectly match your riding style. Coincidentally, the Ultegra chain shifts better on the rear, too, no matter which cassette and derailleur you use. (On my Firefly, rear shifts became a lot crisper with the Ultegra chain, even though the bike uses Campagnolo derailleurs and cassette.)

Many of you will like that we’ve made the chainrings backwards-compatible. If you have a set of Rene Herse cranks, you can just swap the large chainring for an 11-speed one. The rest of the crank is unchanged. It’s part of our commitment to sell you only what you need, rather than forcing you to buy a complete new crankset just because you want to upgrade to 11-speed. The new chainrings are in stock now.

Click here for more information about Rene Herse cranks.

Posted in Rene Herse cranks | 16 Comments

Myth 13: Leaning without Countersteering

Glancing at the photo above, you might think that I am turning right (seen from the rider’s view). Actually, I am beginning a left turn. What you see is countersteering – literally the only way we can lean a bike into a corner.

This post is part of our ‘Myths in Cycling’ series to celebrate Bicycle Quarterly’s 15th anniversary. In these posts, we examine things we used to believe, but which we’ve since found not to be true.

Countersteering is how a bike leans: You move the wheels to the outside of the corner, so the bike becomes unbalanced and leans into the turn. The video above illustrates this as I take BQ’s most recent test bike, the Surly Midnight Special, through an S-bend.

At first, you see the bike leaning to the right (seen from the rider’s perspective) as I finish the right turn. Then I quickly have to lean the bike to the left. To do this, I first steer further to the right. This pulls the bike upright again. I continue to steer to the right, and now the bike begins to lean to the left. Only when the bike is leaning at the desired angle do I turn the handlebars to the left to steer the bike around the turn.

The section in the middle, where the bars are turned to the right while the bike already is leaning to the left impressively illustrates how countersteering shifts the bike’s balance. On most bikes, this happens intuitively – I never thought about steering to the outside of the curve while riding the Surly around those bends. Countersteering is intuitive, because we do it when we walk and run, too. Only when a bike’s geometry is too stable, then we have to actively countersteer to get the bike to turn.

Can’t we simply shift our body weight to one side and make the bike lean and turn? It’s not that simple, because inertia keeps the bike balanced (2): If you move your body right, the bike will move left: Your center of gravity remains centered above the wheels.

That is why you can rock the bike when you climb out of the saddle, yet continue to ride in a straight line.

However, if you continue to lean the bike to the left, the bike’s front-end geometry turns the handlebars to the left. The wheels move to that side, and you get the same countersteering that makes the bike lean right. That is how riding no-hands works: You lean right, the front wheel automatically countersteers, and then the bike leans right and you turn. Presto!

Similarly, ‘steering from your hips’ can turn the handlebars to initiate that countersteering move. However, I suspect that even riders who ‘steer from the hips’ actually turn the bars to countersteer – otherwise, the bike would react very slowly, as it does when riding no-hands.

In BQ 34, we examined these factors in detail. Back then, Jim Papadopoulos and others had just revolutionized our understanding of bicycle geometry: They showed that even a bike without trail and without gyroscopic forces can be stable. We worked with Jim to translate these findings into a clear understanding of how a bike balances and corners. The article provides fascinating insights that have made me appreciate bicycles all the more.

Conclusion: Whether we realize it or not, we are always countersteering when we lean our bikes into a turn.

Further reading:

  • Bicycle Quarterly 34 with the full article on balancing and cornering.
  • The current Bicycle Quarterly with the test of the Surly Midnight Special.
  • Other posts in this series:
    Myth 1: Wider tires are slower
    Myth 2: Titanium is lighter than steel
    Myth 3: Fenders slow you down
    Myth 4: Stiffer frames are faster
    Myth 5: An upright position is always more comfortable
    Myth 6: Tread patterns don’t matter on the road
    – Myth 7: Tubeless tires roll faster
    – Myth 8: Modern components are lighter
    – Myth 9: Fork blades don’t flex
    Myth 10: Stiffer forks steer better
    Myth 11: Rear tires should run at (significantly) higher pressures
    Myth 12: Disc brakes work better than rim brakes
Posted in Bicycle Quarterly Back Issues, Testing and Tech | 29 Comments

BQ Un-Meeting 2018

road_forest

The Bicycle Quarterly Un-Meeting is just a month away! The Un-Meeting is our annual get-together with those who share our joy of riding off the beaten path. It’s not an organized event – we just publish a date and time, and everybody is welcome to join. There are no fees, no registrations, and no services are provided.

When: Sept. 8-9, 2018 (Sat. & Sun.)
Meeting point: Bremerton Ferry Terminal exit (Starbucks Coffee shop)
Meeting time: 9:30 a.m.
Ride distance (approx.): Day 1: 95 km (60 miles), Day 2: 35 km (22 miles)

There are two ride options: The unpaved ride (above) hugs the Hood Canal with beautiful views on a challenging route with many short, steep climbs. For those prefering to stay on pavement, there is an inland route that bypasses the gravel with longer, but less-steep, hills.

ferry

This year’s Un-Meeting is easy to access – the downtown Seattle ferry terminal is just minutes from the train station. We’ll take the 7:35 ferry to Bremerton. Make sure you board the right boat; the ferry to Bainbridge leaves from the same terminal.

We’ll meet at the exit of the Bremerton ferry terminal around 8:45 in front of the Starbucks coffee shop. (This has changed from the previously published time, as the ferry schedule for September is now available.) From here, we’ll start our ride. It’s not an organized group ride, but we usually fall into small groups that stay together.

clouds_hood_canal

Soon after leaving Bremerton, we’ll find ourselves on small roads. After a brief stop in Belfair – the last ‘services’ on the day’s ride – we’ll head along the Hood Canal. These are favorite roads that we’ve traveled during many rides. If the weather cooperates, we’ll enjoy sunshine and great views of the Olympic Mountains beyond the narrow fjord of the Hood Canal (above). (Despite its name, the Hood Canal a natural body of water.)

fog

As we head into the Tahyua Hills, the gentle rollers make way to steep climbs, and the road turns to gravel. Riders who prefer to stay on pavement can use inland roads that climb higher, but are less steep. That route is equally spectacular.

bay

Both routes converge again as we approach Seabeck. We ride along beautiful bays and finally reach the appropriately named Scenic Beach State Park. We’ve reserved three campsites that can sleep 24. If you have a small tent, you are welcome to share our sites. Otherwise, please book your own accommodations. There are also several hotels in the area for those who prefer to sleep under a roof.

seabeck

Also make sure to bring food! Seabeck, the town near our overnight spot, doesn’t have much in the way of services. There is a lovely general store, but don’t expect a huge variety of food options. It’s best to bring your own and augment that with what you find at the store.

On Sunday, we’ll meet at the store at 9:30 a.m.

small_road

From Seabeck, we’ll return to Seattle on beautiful backroads – unless you want to use the Un-Meeting as a jumping-off point to further exploration of the Quimper Peninsula with historic Port Townsend to the North, or the Olympic Mountains with Bon Jon Pass to the West.

bainbridge

When we’ll board the ferry back to Seattle, many old friendships will have been rekindled, and new ones started.

A last word about logistics: The ride is within reach of most cyclists, but the first day’s stage is almost 100 km (65 miles) long; and the hills are steep. The Un-Meeting provides no services and no sag wagon; you’ll carry your own gear. You don’t need a special bike, but there are no bike shops along the route, so make sure your bike is in perfect condition for this ride. And with many sharp corners on both the paved and gravel routes, please use caution and ride within your and your bike’s capabilities.

For me, the Un-Meeting is a highlight of the year. I hope to see you there!

Click here for a preliminary link to the unpaved course. The paved course will be published later.

Posted in Rides | 4 Comments

15 Years of BQ: Plus Ça Change

With Bicycle Quarterly celebrating its 15th year, it’s been fun to look back over the decade-and-a-half of publishing the magazine. A lot has changed, most of all the size:

The first issue was a slim 20 pages, the latest one is more than five times as large!

As BQ grew and resources became available to hire professionals, black & white photos that charitably might have been described as ‘adequate’ have been replaced by beautifully reproduced color photography. The layout has improved, too. The first issues were little more than newsletters; the most recent ones are almost books in their own right.

What hasn’t changed is the quality of the content. The very first issue featured the story of the great French constructeur Alex Singer in comprehensive detail. It started with a fascinating interview with Singer’s successor, the late Ernest Csuka. We published previously unseen historic photos. And there was our first bike test, a 300 km brevet on a 1962 Alex Singer with a Nivex rear derailleur. With a mix of historic sources, original interviews and first-hand experience, this issue remains the best documentation of Cycles Alex Singer to this day.

That first issue also set the tone in another way: Rather than merely reporting what exists, we examined how to improve bicycles. I tested a 1962 Alex Singer in a 300 km brevet and found it to perform extremely well. I especially liked its gearing with 46×30 chainrings. A second article titled “Who Needs a Triple? Get Rid of Your Big Chainring!” suggested that component makers should offer compact cranks. This was at a a time when road bikes still came with 53/39 chainrings, as if we were all gearing up for a downhill Tour de France sprint finish.

Over the following years, Bicycle Quarterly continued to discover the great French cyclotouring culture. Inspired by photos of gravel roads in the Alps, we marveled at bikes that had been perfected for adventures off the beaten path. We realized that our bikes needed wide, supple tires and fully integrated fenders, racks and lights.

This was followed by more research into why these bikes worked so great. First, we studied front-end geometries and discovered that the best-handling bikes had much less geometric trail than most ‘experts’ (ourselves included) considered necessary. Then came our famous tire tests, which showed that wider tires can roll as fast as narrower ones. Later we studied frame stiffness and found that tuning the stiffness to the rider’s pedal stroke (and vice versa) could make bikes perform better. All this revolutionized our understanding of how bikes work.

As this research came along, small custom builders were among the first to adopt our findings. Hence most of our test bikes were what you might call ‘classic’ bikes made from steel tubing. We loved those bikes, and we continue to love them.

For a while, we seemed to inhabit a small niche in the cycling world, where adventurous souls rode beautiful bikes over long distances on scenic gravel roads.

Then the mainstream cycling industry realized that ‘allroad’ cycling (a term we had coined in 2007) presented a real opportunity. There wasn’t just the marketing appeal of rugged adventure, but these road bikes with wide tires actually were a lot more fun to ride than their narrow-tired predecessors. It was a rare case of marketing is backed by substance.

As these new bikes became available, it was natural for us to test them. When carbon and titanium bikes began appearing in Bicycle Quarterly, some readers wondered whether Bicycle Quarterly had changed its focus, or perhaps even ‘sold out’? The reality is that the mainstream bike industry finally has caught up with us.

For a long time, we lamented that it was almost impossible to buy bikes suited for the rides we enjoy. Today, you can go into a bike shop and choose among a large number of bikes designed for spirited riding on all kinds of roads, from smooth pavement to rough gravel. Our readers want to know how good these bikes really are – so we test the most interesting ones. Bicycle Quarterly never was about being retro; it’s always been about having more fun on your bike.

Where does the future lead? There are more discoveries to make. Rinko allows disassembling a complete, fully equipped bike into a small package with minimal tools and almost no modifications to the bike. Perhaps the mainstream bike industry will adopt this idea in the future, making life easier when we travel with our bikes.

We are exploring new tire treads that roll as well on pavement as they grip in mud. And we’ll keep pushing for bikes that fit our adventures, which include riding in any weather, even at night, unsupported. We are looking forward to the next 15 years. If the past is any indication, it’s going to be a fun journey!

Click here for more information about Bicycle Quarterly, including a sample issue you can browse online.

Posted in Bicycle Quarterly Back Issues | 32 Comments

Disc Brakes in the Tour de France

This year’s Tour de France has had its share of drama, and the winner won’t be the one most observers predicted. Among the sporting achievements, the technological innovation was easy to overlook: Finally, the UCI approved disc brakes, and the Tour is the first big stage race where they’ve been used.

Reading the previews of Tour bikes, it sounded like all racers would make the switch. Just in time for the big race, several big bike manufacturers rolled out new race bikes with disc brakes that approach the UCI-required minimum weight. With no weight penalty to speak of, adopting disc brakes seemed like a no-brainer.

After all, brakes are maybe the most important components of a racing bike. When Mafac introduced their first centerpull brakes in 1952 (above), it didn’t take long until almost all racers adopted them, so superior was their performance. It didn’t matter whether they rode for French, Italian or even the ‘International’ teams – braking hard before the corners was more important than allegiance to national sponsors. And when Campagnolo rolled out their sub-optimal ‘Delta’ brakes, racers refused to use them. Campy backpedaled and resurrected their old sidepulls in a hurry. With disc brakes being heralded as the most important innovation in decades, most expected shiny metal circles to appear on the hubs of the entire peloton.

And indeed, during the first stages, most teams rolled out on bikes with disc brakes (above the finish of Stage 5). Ironically, most of the disc brakes were on aero bikes used for flat stages, where brakes make no difference in the bike’s performance.

As the race continued, most racers quietly switched back to rim brakes. The yellow jersey contenders had used rim brakes from the beginning. Why?

The racers were concerned about flats. Through axles require extra time during wheel changes. Worse, the inevitable manufacturing tolerances change the alignment of the disc rotors on different wheels, even if the same model of hub is used. Unless the disc calipers are adjusted, the new wheel’s rotor will rub. (We realized this during our most recent tire tests, where we thought we could speed up the changes between different wheel sizes, but had to adjust the disc brake calipers after every run.)

BMC Racing found a work-around solution to the problem: When a rider flats, they don’t change wheels, but the entire bike. However, this also means they no longer can use neutral support. Most other teams weren’t willing to run that risk.

When the Tour entered the mountains, many observers expected the racers to switch back to disc brakes.

If disc brakes have an advantage, it’s on the vertiginous descents of the Alps and Pyrenees. Since racers have moved to wider tires with more grip, descents have become much more exciting, with higher speeds and more attacks than in the past. Braking is more important than ever. And yet, there was hardly a disc brake in sight.

What happened? I asked a former mechanic of the French national team. He indicated that the introduction of disc brakes was due to sponsors’ demands. With the big component and bike makers pushing discs, it was useful if pro racers used the new technology.

So why did the racers use rim brakes when their sponsors wanted them to use discs? If discs were superior, racers would have used them, especially in the mountains. After all, a real advantage on the many descents of this year’s Tour would have outweighed the relatively small risk of losing time due to a wheel change.

The answer is simple: Really good rim brakes stop just as well as even the best disc brakes. And many riders find that rim brakes offer superior feel: The brake lever is directly connected to the rim via a cable, rather than having the feedback dulled by the wind-up of the spokes and by hydraulic fluid. It’s refreshing that even today, where bike racing has become big business, winning races still is more important than pleasing sponsors.

In the future, I expect that the problems with wheel changes will be overcome by standardizing the disc location. A friend has already done this, using thin washers to make sure all his wheels fit all his bikes without adjusting the brakes. It’s a lot of work, and team mechanics will not be happy…

Rotors will also have to be standardized – currently, teams use both 140 and 160 mm on the front – to simplify neutral support. And then, the sponsors finally will be able to showcase bikes with disc brakes in the Tour. For now, it’s clear that disc brakes don’t offer a big advantage over the best rim brakes.

Back in 1952, it was different: Centerpull brakes swept through the pro peloton. With their pivots placed next to the rim, they offered greatly superior stopping power and modulation to previous brakes. In fact, the rim brakes that dominated the 2018 Tour de France use the same principle – only the actuation is different to eliminate the need for straddle cables and cable hangers.

Further reading:

Photo credits: A.S.O./Tour de France.

Posted in Brakes, Testing and Tech | 65 Comments

New Products and Back in Stock

We are excited about a number of new products. MKS has reworked their popular Sylvan pedals with silky smooth cartridge bearings. Now called the Sylvan Next, we’ve carried the Touring version for a while. New in the program is the Track pedal (above).

The new Track pedals are a great choice not just for track riders, but for all riding with cycling shoes and toeclips. The cut-away pedal body provides better cornering clearance and reduces the weight, while still offering full support for the shoe. Eddy Merckx used to race on track pedals because of these advantages.

What is the difference to the Touring version (above)? The platform of the Touring pedal is wider, so giving you the option of riding comfortably in street shoes, too. And since it’s double-sided, you can use it with or without toeclips. The Track pedal is easier to use with toeclips, since the flip tab at the bottom helps with rotating the pedal to insert your foot into the toeclip.

Both pedals are available in ‘EZY Superior’ Rinko versions, which allow removing the pedals in seconds without tools – great for travel bikes and for cyclists who ride one bike with multiple pedal systems. Removing the pedal couldn’t be simpler: Turn the ring on the adapter, push it inward, and the pedal releases.

Our Compass Switchback Hill 650B x 48 mm tires have been very popular, but until now, there were no fenders to go with them. We asked Honjo to custom-make their smooth 62 mm-wide fenders in a new XL version for us. With a larger radius, these fit perfectly over ultra-wide 650B tires (up to 50 mm wide).

To provide clearance for the chain with road cranks, fenders cannot get wider than this, so this fender does not wrap quite as far around the tire as our fenders for narrower tires. It still provides better spray protection and more tire clearance than any other fender we’ve tried.

Pacenti’s Brevet has become our most popular rim: strong, reasonably light and without the cracking problems that bedeviled many recent rims, it’s proven reliable and easy to build. It’s also tubeless compatible. We are excited to offer this excellent rim in new 700C versions, as well as the well-known 650B.

The HED Belgium Plus is one of the best modern 650B rims out there. It builds straight and the diameter is spot-on, making tubeless installations a snap. We’ve persuaded HED to keep it in production, and the rim-brake version now is back in stock. Disc brake rims will arrive soon.

Gilles Berthoud’s underseat bag is a great way to add carrying capacity to a bike that doesn’t have provisions for luggage. It holds a rain jacket, arm warmers, a wallet and some food in addition to spare tubes and tire levers. It’s made from the same waterproof cotton with leather edging as Berthoud’s famous handlebar bags that last (almost) forever.

We now carry these bags with a more secure leather buckle closure. The previous elastic has worked great for me, but since you won’t access a saddlebag while riding, the two-handed operation is no problem, and you no longer run the (admittedly small) risk that the elastic breaks, spilling the contents of the bag onto the road.

The Berthoud saddle bag attaches either with straps to the rails of your saddle, or with a KlickFix adapter directly to most Gilles Berthoud saddles (above).

Our handlebars combine modern materials with classic ergonomics. Their generous shapes provide room to roam during long days in the saddle. Now all sizes are back in stock.

The Compass taillight has been very popular. It combines a beautiful shape with modern electronics: a powerful LED and a standlight circuit so you remain visible when you stop. It incorporates a reflector. Mounted between the seatstays, it’s visible from where it matters, yet it’s well protected. Our taillights are made by a good friend right here in the U.S., and we’ve had a hard time making enough to keep up with demand. Now they’re back in stock.

Click on the images above for more information, or click here to check out the complete Compass Cycles program.

Posted in Fenders, Pedals, Product News, Tires | 7 Comments

How Wide is Right for Me?

open_corner

Our ideas of what is a performance bike have changed a lot in recent years! One of the most exciting bikes of the moment is the Open U.P. – a carbon race bike that accepts 50 mm-wide tires!

Not too long ago, every performance road bike had 700C x 23 mm tires. Now you have to choose not just how wide you want your tires to be, but – thanks to disc brakes – even which wheel size you want to use! For the Bicycle Quarterly test, we rode the Open with 650B x 48 mm tires, but our second tester, Nate King, raced his Open with 700C x 44 mm tires. Which is better? Or should you get several wheelsets for different courses? Is there a reason to switch tires and wheels on the same bike?

tire_test

Let’s first talk about some fundamentals: Wider tires don’t roll slower than narrow ones. Bicycle Quarterly‘s latest tire tests, published in the Winter 2016 issue (BQ 58), have shown this once again: In a real-road scenario, even 54 mm tires don’t roll slower than 32 mm – or any size in between. Before this, we already tested tires between 20 and 32 mm tires and found that the 20 mm and 23 mm were slowest, and all the others offered the same performance.

By the way, we tested at 22 mph, so this factors in the greater air resistance of the wider tires. It appears that wider tires have slightly lower rolling resistance, which cancels out the small increase in wind resistance. This means that at lower speeds, wider tires probably are faster than narrower ones. We tested on very smooth asphalt. On rougher roads, wider tires also are faster.

Yes, I know it’s not what we used to believe – we were quite surprised when we saw the results of our testing, but we’ve confirmed this time and again. And so have others in recent years.

To summarize all this research: Narrow tires (<25 mm) are slow. Above 25 mm, the width of your tires are won’t change your speed (at least up to 54 mm wide tires).

That doesn’t mean you can just slap any wide tires on your bike and expect it to go fast. What will change your speed is how supple your tires are: Tires with high-performance casings are faster, more comfortable and offer better traction, regardless of their width. If you choose heavy, reinforced ‘touring’ models when you switch to wider tires, you’ll likely to be disappointed – they’ll roll slower than racing tires because of their sturdy casings, not because of the extra width.

So we know that supple casings are key, and that width doesn’t matter. What size tires should we run then? Is wider always better? And what about wheel size?

open_paved_corner

Wider tires offer more cornering grip. This is true for racing cars and motorbikes as well as bicycles. On bicycles, there are two reasons for this: More rubber on the road gives you more traction. And wider tires are inflated to lower pressures, which means that they stay in contact with the road. If your tires don’t bounce over small irregularities in the pavement, they have even more traction than their width alone would suggest.

If you like to corner fast, you want the widest tires possible. Even on smooth pavement, the difference between 38 mm and 48 mm-wide tires is noticeable, and on rough surfaces or even gravel, it’s no contest.

WheelTest

Wheel size is another important consideration. The photo above shows three Bicycle Quarterly test bikes with identical geometries (head angle, trail, BB height, etc.), but different wheel sizes. What we found in that test: Wheel size greatly influence the handling of your bike. Larger wheels make the bike more stable, and so do heavier wheels – it’s the rotational inertia that matters, not the outer diameter.

Since wider tires are (slightly) heavier, you’ll want to decrease the wheel size to keep the rotational inertia – and thus the handling – the same. That means that your wheel size should be chosen based on your tire width and tire weight. That way, you can enjoy the nimble handling of a great racing bike even with wide tires.

Let’s a look at a few tire sizes that I enjoy riding, with their pluses and minuses:

ritchey_swissx

38 mm wide

  • To me, tires narrower than 38 mm don’t really make sense any longer. 38 mm tires still give you the “connected to the pavement” sensation that makes a racing bike feel so fast. Below 38 mm, all you gain is harshness. The bike doesn’t feel any better, just more jiggly.
  • 38 mm tires are great for pavement and occasional gravel riding.
  • To go with 38 mm tires, you have a choice of wheel sizes:
  • If you like the nimble handling of a racing bike, then choose 650B wheels for 38 mm tires.
  • If you prefer a bike that locks onto a cornering radius and won’t be deflected even if tense up in mid-corner, then use 700C wheels for 38 mm-wide tires.

hahn_shiretoko

42 – 44 mm wide

  • Adding 4 mm to the width of your tires gives you some added plushness – compared to 38 mm, you’ve increased the air volume by 22%.
  • In exchange for that added cush, you lose a little bit of connection to the road. To me, that isn’t a big loss, and I enjoy the greater traction and go-almost-anywhere capabilities of the wider tires.
  • For tires this wide, 650B is the optimal wheel size.
  • 42-44 mm tires are fine for most gravel riding. They have the advantage that good rim brakes (like our Compass centerpulls) fit over them – even with fenders. In fact, fender mounting becomes a compromise with tires wider than 44 mm (see below).

gravel_hairpin

48 – 54 mm wide

  • Now we are getting into some seriously wide tires for a road bike! A 54 mm tire holds twice as much air as a 38 mm tire.
  • Tires this wide change their feel depending on the pressure you run:
    • With the tires inflated to 38 psi (2.6 bar), our Open U.P. test bike felt like a road bike. The tires made more noise as they rolled over the pavement, but otherwise, the feel wasn’t all that different from narrower tires.
    • Letting out some air and reducing the pressure to 26 psi (1.8 bar) changed the bike completely. Now it was super-plush. The tires still had enough air so they wouldn’t collapse under hard cornering, but I could feel the ‘suspension’ when riding out of the saddle. At this pressure, the tires were ideal for rough gravel.
  • For tires this wide, I definitely recommend 650B wheels. With 700C rims, your bike will just plow straight ahead like a 29er mountain bike, and you’ll need suspension to absorb the bumps that you cannot steer around. On my Firefly (above), I went with 26″ wheels for a more agile handling. As a result, the bike feels remarkably similar to a good racing bike.
  • Fender mounting is an issue with tires this wide and road cranks: Ideally, a fender should be about 20 mm wider than the tire, but the chain will hit a fender that is wider than 62 mm when riding in the smallest gear! The solution is using a 62 mm fender that doesn’t wrap around the wheel very much and mount it a bit higher above the tire. It works, and we now offer a 650B fender specifically for 47-48 mm wide tires.

otaki_07

How about tires wider than 54 mm? That might be interesting, but you can’t really fit them between road cranks with narrow Q factor. 54 mm tires already are quite wide: They have the same air volume as 2.3″ mountain bike tires – it’s just that they don’t have knobs on the shoulders, so they measure out a bit narrower. Below is a comparison of the air volume of my three favorite tire sizes (to scale).

38-54-mm-tires

To summarize, if you want your bike to feel connected to the pavement like a good road bike, I recommend 650B x 38 mm tires. Compared to narrower tires, you get added comfort and speed on rough pavement, and more cornering traction, too.

I prefer a little extra rough-road performance and even better cornering traction, so for paved rides, my choice is 650B x 42 mm. You lose a little of the connection to the road, but during hard cornering, you actually get more, not less, feedback of how much traction you have in reserve, because the tires can really key into the pavement.

If my ride includes a lot of gravel, I’ll pick 650B x 48 mm or even 26″ x 54 mm. On pavement, the downside is that you get some tire roar – how much depends on the diameter of your bike’s frame tubes that provide the resonance chamber for the noise – and the tires’ feel is more sensitive to tire pressure. On the plus side, the traction in paved corners will blow your mind.

If you are using lightweight carbon rims and superlight tires, like our Compass Extralights, then it makes sense to go up one wheel size to compensate for the lighter weight. So for 38 – 43 mm tires, I’d recommend 700C wheels, and 44+ mm tires, I’d use 650B. Otherwise, your bike gets that ‘small-wheeled’ feel: The bike doesn’t hold its line on its own, but requires active input from the rider to go straight. It’s not a big deal, but we are talking about optimizing your bike here.

It seems that more and more riders are converging on these tire sizes: BQ‘s second tester for the Open U.P. recently received the latest model from his sponsors (above), and he spec’d it with 650B x 48 mm tires – like our test bike. And he tells us that he loves it!

With these suggestions as a starting point, I recommend test-riding a few bikes with different wheels and choosing the ones you like best.

Resources:

Photo credits: Toru Kanazaki (Photo 8), Natsuko Hirose (Photos 1, 3), Nate King (10).

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