Hiker news #3

After some holiday time-off from Hiker and other work, we are now back in our offices and starting to roll things forward again.

Just before christmas we heard that our second round of test forks did not pass the safety test either. We still had made them too flexible, and they bent quite massively in the “Static braking test” where a 1000N force is applied for 60 seconds onto the tips of the fork blades. It begins to seem like it is not possible to make a very thin and supple front fork while fulfilling the EN ISO requirement, which is not a huge surprise. But we had to try, even if it cost us a small fortune. Our next idea is to use a super strong material, a heat treated high end steel which will resist cold-setting more and thus should do much better in static bending. This should help the forks pass the test without making them overly stiff and heavy. We will still probably need to make them more stiff than they are now.

We are quite certain that even the non-approved forks would be safe to use at least for the small and medium sizes. I don’t remember ever seeing a front fork that had bent due to hard braking, and searching on the internet I couldn't find any examples either. But we are not sure if we can afford to take a risk like not having the safety certification.

Some other stuff to do is to try and think on the final colours, continue on the stem/decaleur/rack designs, plan on the possible complete bicycle and which parts would that use and so on. And of course to try and work on some advertising!

To let you better understand our point of view on bicycles, we present to you the following article which hopefully sums up the most important ideas concerning why and how we designed our first model. It’s written by me, Aki, and I believe my colleagues will agree for the most part if not completely.

Hiker design philosophy

The world is being filled with crap at an ever increasing speed, which makes me doubt the whole idea of producing more bicycle frames in the first place. Old bikes work fine. But then I have to admit I have a very particular taste in bicycles, and there are not enough used mid-century french cyclotouring bikes to go around for everyone. And not everyone considers restoring one a nice and fun project… And because I believe in my own opinions and feelings, I think other people might find similar bikes fun and useful as well. This is how I ended up in the Hiker project.

So, if we’re going to introduce a new product to this world, let’s try and make it without cutting too many corners. True economy, meaning least resources spent, is not the same as “economy” in the everyday sense, meaning cheap. This is why our design has lots of stupid and difficult solutions considering efficiency of production. Three different wheel sizes, three different forks, 7 different frame sizes with most of them with every tube of different strength all adds to the cost. Add the fancy fork bend, custom chainstays and minor details like that. Most customers aren’t going to see that cost, but many will just think that “Oh, the Hiker costs 40% more than a brand-X steel frameset, but it’s just an ordinary TIG-welded powder coated frame like the other one.” This is why we need to believe there are enough geeks out there who will see the added benefits… Those who believe that the whole is more than its parts listed in an excel sheet or a product description list. Best would be to have people test ride it of course, but that will be tricky to arrange for most customers outside of Helsinki.

Geometry

I'm not the type who believes in linear progress. I'm more bent on cyclicism and golden-age thinking. Like digging Minoan culture in 2000 BCE: peaceful, prosperous, artistic, led by a belief in the Goddess, before aggressive hordes of barbarian men ruined everything for everyone, that sort of thing. This is why I don’t have a problem using a 1950s geometry that someone would consider outdated. To me, it’s tried and true. Possibly the world has even gone in a worse direction since then! At least the laws of nature which finally dictate bicycle handling are not evolving, I think? The Hiker geometry is based on bicycles from the cycle touring golden age, inspired by designs of makers such as René Herse in France and Jack Taylor Cycles in Britain. Most measurements on the Hiker have been also compared to my late 1940s french touring frame by Allegret & Desbeaux that I have ridden extensively and have been very happy with. We wouldn’t buy geometry in a bag without trying it out first!

My bike called Myyrä, the proto-Hiker. The frame dates to the late 1940s

Anyway, much more important than “progressive geometry with insert-new-radical-design-here” is to make the different sizes fit well. First of all, you can’t claim to have the best geometry for everyone and everything in a production frame. That’s why we have chosen to optimize the frame for relaxed-ish and comfortable long-distance and everyday riding. The frame will be too tall for most people concerned with short-term aero-optimization or those who want to be positioned aggressively for high power outputs. Having a “fast” and aggressive geometry can be fun when you’re feeling fresh, but after that feeling is used up and you’re getting tired, you will appreciate completely different characteristics. 

To make the frame fit really well, we decided to scale not just the frame but also the wheels. The framesets use 3 different wheel sizes. This makes it possible to avoid many compromises in design. Take for example the smallest size: most production frames have much longer top tubes, and thus longer reach to not run into the problem of toe overlap. This makes it very difficult to use drop bars comfortably on these small bikes. Most manufacturers dont want to use the difficult 559/26” wheel size that is going out of mainstream fashion. And also because they dont want to make separate runs of front forks for this size, which would decrease their margins. 

Frame design

Frames used to have level top tubes for almost a century. I consider this “pure” geometry, with no long cantilevered things sticking out of the too-small frame of so-called compact bikes. Compact frame design is a different approach, and it can work: a small steel frame with long non-steel seatpost and stem is naturally a lighter assembly, and you get a possibly stiffer frame and a longer, more flexible and thus more comfortable seatpost. This design is not necessarily as strong though. But on (all-)road bikes where standover is not really an issue, I prefer the simplicity of the level top tube. With my mind’s eyes I can imagine the bike under the rider, with force vectors from the saddle to the handlebars bending the frame sideways. To me it makes sense to have the top tube align directly with these vectors, and not be in an angle. It’s quite hard to prove anything completely and finally, and this is maybe one of those things.

We use chainstays a few centimeters longer than the minimum, which is what most other designs aim for. Making them longer adds space for fenders, tires and chainrings, while at the same time making the bike more stable. Which is exactly what you want on a comfort-oriented bicycle. The bike will track a straighter line. Also bumps hitting the rear will be offset further from the saddle which decreases their magnitude when they reach your body parts.

To keep the chainstays stiff laterally even with the added length, we use a round/oval/round chainstay that is stiffer than the nowadays standard fully oval chainstay. The medium and large sizes (57 and up) also use custom made extra-thick wall chainstays from Columbus.

Tubing stiffness and strength

Here is our tubing chart for the frames. The colors indicate stiffness progression, green being most flexible, yellow medium and so on. SL, ZONA etc indicate the manufacturers’ model name. The first number below is the tube’s outer diameter in millimeters, and the second number is wall thickness. For example, the top left corner is a Columbus SL top tube with an OD of 25,4mm and butted wall thickness of 0,8mm in the ends and 0,5mm in the middle. 

As you can see from the chart, the 7 different frame sizes scale not only in size but with progressive rigidity of the frame and fork tubes. The small sizes use thinner, thus lighter and more flexible tubing. The medium sizes use tubes that are a bit stiffer, and the largest sizes have already considerably heavier tubing.

This is due to the fact that tubes will flex more as they get longer, so by scaling the tubes the overall rigidity does not decrease when going to a larger frame size. We also assume people get heavier as they get taller, so the larger frames are built more robustly.

The progressively stiffer tubing used across the range is specified with a light-ish, careful and not-overly-powerful rider in mind. The type of riding we imagine the bicycle doing is quick and steady but not hurried nor forced pace, and without the need for a final sprint, where extra rigidity might be needed. A flexible, more comfortable frame is easier to pedal without large power-input. This might hold you back in a race if you have that large power, but the softness will aid you on a ride when you are tired and weary, or even better, keep you from becoming tired and weary in the first place. 

We could have made the frame a bit lighter by using oversized extra-thinwall 0,4mm tubes instead of the thicker wall but smaller diameter tubes. But this would make them more prone to denting and rust. The tubing has been chosen for comfort, decently light weight and durability.  Like you might notice, not every tube is different between every size, which would be ideal of course, but I do think our system is quite elaborate already. I don’t think most manufacturers scale their frames even close to this extent.

Many high-end steel framesets nowadays use ovalized tubes, but honestly we did not have the capacity to think that far. How I see it, they might add some marginal benefits, but they might also add some marginal oddities that round tubes will not have. There is some overly theoretical computer aided design -vibe in oval tubes, like you could take one part of the bicycle frame and optimize that without considering all the other variables. Round tubes are proven to work well all-a-round. Maybe Hiker version 2 one day will have ovalized tubes, maybe not.

Size 53 from the first batch of prototype frames. Subject to change.

Fork design and brake choice

Like stated, comfort is one of the main priorities of our design. The front fork plays a very big role here, as it has the potential to flex much more than the rigid diamond shaped frame. This is one of the main reasons why we did not choose disc brakes, as this would make it impossible to design a properly flexible front fork. The disc brake acts on one side only, highly stressing the left fork blade, which then needs to be made extra strong.

For the brakes, we did consider using braze-on centerpulls, which probably are better than cantilevers, but as they limit the fender and tire clearance to about 52mm and 42mm, we opted for the more common cantilever brake instead to be able to run 48mm tires with 60mm fenders, or even larger tires without.

The original idea was for the fork to have extra thin blades with plenty of rake concentrated near the dropouts for maximum suspension. But as the demands of the EN ISO tests have made themselves very apparent, we need to figure out how to sacrifice the least amount of compliance and still pass the test.

Whatever the final strength and stiffness of the fork will be, the three different wheel size specific forks are of course adjusted for the different loads of the different sized riders. We might even end up making a not-EN-ISO-approved fork for the smallest size, as the test is thought to cover a system weight of up to 100 kgs, and our smallest frame is designed for riders much lighter than that.

Wide tires

The reasons bikes had wider tires back in the days (pre-1950s) were a bit different: there simply were no good smooth roads. Now there are “good roads” but those are taken over by automobiles, and the good roads for cycling now are mostly byways and small gravel roads. So the end result is the same: one will want about 42-48mm wide tires to ride on those roads too bumpy and slow for cars. And if you use high quality supple tires, the wide ones won’t slow you down much at all even when the road is smooth.

The Hiker fits a 48mm true-to-size tire with fenders. Or about a 54mm tire without fenders. This is with decent clearance left over that won’t be filled with debris too easily, or if you break a spoke you can most probably still ride home. 

Real-world compatibility

The weather here in Finland doesn’t suck completely, but it can be challenging! I had to check some statistics: on average it rains on 192 days of the year in Helsinki where we live. This means proper mudguards are a great help in staying comfortable. And it is very dark half of the year… You will need lights. This means dynamo systems are super useful. Also the comfort-oriented geometry, not overly thin tubing walls etc are all designed to work in everyday life.

A bag to carry things with

In the real world one needs supplies. This means it’s handy to have a bag attached to the bike. This is a crossroads in bicycle design: do you load the front or the rear? Both have their merits and pitfalls. Someone might argue that a framebag is the best answer, but I don’t consider it very handy in everyday use as it’s tricky to take off and the shape doesnt accommodate random shaped objects well at all. 

One could argue, and this is what we chose, that loading the front distributes the weight better on the bike, as most of your body weight is already on the rear wheel. The load is also constantly visible, and with a smartly designed bag can be accessed while riding. For photography it’s quite handy to not have to get off your bike to take out your camera. Or to eat some fruit, add or remove pieces of clothing and so on.

The geometry of the Hiker is optimized for this front load. The steering can feel a bit too sensitive without any front load, depending on what you are used to. But with a few kilos in the bag, the steering slows down just the right amount, while still maintaining agile handling.

We cannot recommend loading the bike up super heavily. We wanted to ensure a light and lively feel instead of high carrying capacity. You can load it up for a tour, but make sure you pack sensibly. Large rear panniers are probably not going to work well with the flexible frame.

The vision

We started out with the basic idea: a comfortable lightweight steel frameset for real-world conditions. The important decision was to try and make it as well as possible, not fearing the added cost too much, while also avoiding unessential add-ons that do not directly contribute to the usefulness or ride feel. The second important decision was to clearly outline the nature of the bike, and not end up making an overly compromised product that kind of fits everything and everyone and can be built up in any way. Even with, or maybe because of its limitations, we feel the Hiker is a good all-rounder for most types of riding, with the exceptions of racing, mountain biking and heavily loaded touring. A good standard bicycle.

Until next time,
Hiker Crew