Extra comfort on your bike does not have to be expensive. The Bicycle Fork tested different solutions. We chose a common vowel road as a test course. With simple and cheap interventions, we succeeded in reducing the vibrations on a city bike by 57 percent.
How has it been tested?
With a test bike we have driven at 20 kilometers per hour on the same. For each test drive we have changed one part – a suspension seat post for example – to determine the extent to which it succeeds in damping vibrations. We measured the vibrations on the handlebars and on the saddle. The vibration meter registers the acceleration a hundred times per second. The measured values were then converted to an average value. As a starting point for the vibration test we have taken a bicycle with a fixed saddle, a rigid front fork and Schwalbe Big Apple tires with 4 bar tire pressure. We have taken this bicycle as a standard (100 percent) in order to be able to determine the effects of the different components.
You can increase the comfort of your bike the fastest and easiest by driving with soft tires. A pressure reduction from 4 to 2 bars immediately yields a spectacular result: 32 percent fewer vibrations on the saddle and 35 percent less on the steering wheel.
But of course, you cannot reduce the pressure with impunity. Each tire requires a minimum pressure. If you drop below the recommended pressure, the tire will wear out quickly and you will have a better chance of punctures. The minimum pressure depends mainly on the width of the tire: the wider the tire, the lower the minimum pressure. A tire with a width of 37 millimeters is fitted on most city bikes. The minimum pressure is about 3.5 bar.
If you want more comfortable cycling with soft tires, you will have to fit wider tires. The Schwalbe Big Apple for example. It has a width of 50 millimeters and the minimum pressure is only 2 bars. Unfortunately, many bicycle fork are not suitable for wide tires. The maximum width is limited by the space at the frame, the brakes or the mudguards. Fortunately, more city bikes are equipped with standard wide tires.
Of course, softer tires have a higher rolling resistance. But that disadvantage is highly dependent on the subsurface. On smooth asphalt it is advisable to cycle with inflated tires. But on a bad road surface you can drive faster with soft tires. The vibration reduction not only provides more comfort but probably also more speed because the bike and rider are less shaken.
Not all tires are equally good. Smooth tires appear to be better feathered than rigid tires. We compared the Schwalbe Big Apple with the Schwalbe Marathon Plus. With a Marathon Plus your saddle vibrates 25 percent more, because the belt is stiff and has a thick anti-puncture. For the comfort you better buy the smooth Big Apple. An additional advantage is a low rolling resistance. But because of the thin anti-spill layer you have a greater risk of tire problems.
Suspension seat posts
The traditional solution for more comfort is a saddle with springs. But the saddle of Lepper turned out not to bring any comfort improvement. Now this is a saddle with rather stiff feathers. But do not expect miracles from saddles with smoother feathers.
Resilient seat posts can significantly increase the cycling comfort. We have placed two different models over the klinkerweggetje. The Suntour SP and the Airwings Evolution. The Suntour is a seat post with hinged parallelogram and elastomeric suspension. This combination provides a vibration reduction of 20 percent on the saddle. The Suntour SP has a low price and a solid construction. The Airwings Evolution is a seat post with a normal construction whereby a bar with saddle slides into a tube with springs. With cheap seat posts, this construction provides quick play. With the Airwings not because the pin is equipped with a linear ball bearing. The construction makes the seat post expensive. The Airwings gives a vibration reduction of 27 percent and thus provides a little more comfort than the Suntour SP. But the Airwings tends to mess. You notice that especially when you cycle over a speed bump. Another disadvantage is that the pin springs in the direction of the seat tube. That gives the feeling that your saddle wants to get away from you. The suspension of the Suntour SP in the direction of the back feels much more natural.
Mounting a spring seat post is easy. There are two points to look out for. The diameter of the seat post must match the inside diameter of the frame. If you have too large a frame tube you can buy a filling bush.
In addition, there must be sufficient space between the top of the frame and the saddle rail. For the Suntour SP this is about 12 centimeters and for the Airwings 13 centimeters. If you want your saddle lower, you cannot mount these seat posts.
A suspension fork increases comfort for your hands, arms and wrists. We have tested two models. The RST 801 and the Post Moderne Cozy – SL. These are simple suspension front forks with only steel springs and a simple elastomer damping. These front forks are also frequently used on city bikes. The vibration reduction of these front forks appears to be small. At the RST this is only 7 percent. The Post Moderne performs slightly better and gives a reduction of 11 percent.
Mounting a new front fork is a difficult job due to the parts you have to transfer and cutting the front fork. When you buy, make sure you have the correct size of fork tube (1 inch or 11/8 inch) and the type of steering head bearing (with wire or cordless). And beware: when replacing an ordinary low fork with a high suspension front fork, the geometry of the bicycle fork changes.
Fitting wide, flexible tires and a sprung seat post is simple, inexpensive and delivers a lot of results. Of course, you can also combine soft tires with a sprung seat post. The gain in comfort with Big Apple tires at 2 bar and the Airwings saddle is impressive. The vibrations decrease by 57 percent. The only problem may be that the straps or seat post do not fit. We do not recommend replacing a rigid fork with an inexpensive suspension fork: it is a lot of work and produces little results.