Testing and recording bicycle bells

In most countries of the world it's a legal requirement to have a method of warning people that you are approaching on a bike. In some countries, such as the UK, the human voice is considered to be adequate. In other countries, such as the Netherlands, a bell is a legal requirement on a bicycle.

I've got a bunch of bicycle bells here at the moment as we've wanted for some time to have these available in the webshop, and as with other things in the shop, I've specifically bought in those that we like. However, rather than just listing the bells, I decided we should do this well. Let's test them to find out how loud they are, and also have sound samples so that people can hear what the bells sound like. And here are the results, ranked in order of how loud they are from one metre away, and with recordings of each bell. Click on their pictures if you'd like to buy them:

	Widek 80 mm Ding Dong bell (€9.88)	106 dBA
	"Ping" bell (€2.50)	100 dBA
	Gazelle handlebar grip bell (€25 for pair of grips with bell)	98 dBA
	Spanninga "Turning" bell (€3.09)	96 dBA
	Classic Brass bell (€5.83)	96 dBA

If you have space for it on your handlebars, the Ding Dong bell gives the most sound. Note that there are many copies available of this bell, often painted in different colours, and all that I've heard sound dull in comparison. It's rather subjective, but to me it also gives by far the best sound of the bells. Just listen to that sustain. The Ping bell, which is smallest and weighs just 20 g, is best for those with limited handlebar space or who are concerned about weight, but while the sound is loud, it has little sustain so is not really as effective as a traditional bell. The Classic Brass bell has a remarkably pleasant tone due to the brass, and 96 dBa is still very loud.

And for the geeks amongst us, this is how it was done.

I used my old Radioshack sound-level meter to find out how loud the bells were. Each bell was held one metre from the SPL meter. These tests were all done in the same way, so they are directly comparable with one another. However, because this was done indoors and with reflective surfaces (the wall and table) nearby, you would get different figures if you measured out in the open. Each bell was rung a few times in succession, as you might if you thought you were about to collide with someone. I think it's reasonably representative of what you might do if you were really trying to get someone's attention. With a single ring, the slow rise-time of the analogue meter missed the peaks. As a result, this helped the ping bell result more than the others. A single "ping" doesn't really sound louder than some of the quieter bells. The loudest bell subjectively with a single ring was definitely the ding dong bell.

In any case, the peaks were quite a lot louder than the figures here. By the end of the test, it was not only the bells, but also my ears that were ringing.

These and other practical components for
bicycles are available from our web shop

A Sony WMD6C "pro" walkman was used to make the recordings. I'm not a big fan of Sony, but this was always a splendid product. I found the quietest room in the house, and used a long microphone lead so that I could be at the opposite end of the room from the recorder. I did in in this way for two reasons. First because I wanted to get away from the fan noise of the computer - the walkman is much quieter and easily portable - and secondly because I liked the idea of playing with the walkman again. It's a great piece of equipment which I now rarely use. Yes, an analogue recording on a cassette, but not any old cassette deck. The recordings give a pretty good idea of the sound of each bell, though reproducing the sound at a level anything like so loud as in real life is actually quite difficult to do.

I'm not going to pretend I don't care about technical issues, around cycling or anything else. I don't think it's cool not to know stuff. I'm proud to be a geek...

This blog post can also be read on the DutchBikeBits,com blog.

A proper obstruction

Dutch cycle paths are not completely perfect. Nor are the roads. There are over 29000 km of separate cycle paths in this country and 120000 km of roads. It would be a miracle if all of it was perfect in every detail all the time.

Mostly the problems are quite minor, and the result of older provision not having been updated, or surfaces being a bit past their best. However, very occasionally you find something which is simply bad design.

On a recent ride to visit a friend in Deventer, I came across this example. It was not on the main route, and I shouldn't have been here. I only found it after making a wrong turn into a housing estate. As you can see, I had to get out of the Mango and pick up the back end to turn through this tight corner between unnecessary barriers which had been put in the way.

I suspect this also causes problems for people who have child trailers, bakfietsen, or any other more unusual bikes.

Nowhere that you have to get off your bike and lift it can be classed as good quality infrastructure. It's precisely the sort of nonsense that is so readily and commonly criticised in the UK. Indeed, I used to criticise it myself. And there's a Dutch website which keeps a log.

However, the big difference is in the frequency with which you find such things. This is only the second such obstacle that I've found in the three years that I've lived in the Netherlands, and I had to travel 60 km and accidentally take a wrong turn through a narrow alley to find it. In Cambridge, I could find any number of such things within a very short distance from home. So many, in fact, that I stopped bothering to take photos and update the website on which I put them.


Grotere kaart weergeven

The other horrible barrier that I found is here. It's worth pointing out that the only reason I found this obstruction in Raalte is because I was seduced into going too far along a very nice cyclepath in the town. It was when I decided to change direction that I found this short path and its barrier. Raalte has plenty of other good cyclepaths which make the efficient network needed to support a high cycling rate.

Non-stop relaxed cycling in Utrecht

Another of Mark Wagenbuur's videos. He says: A bicycle friendly junction in the historic city center of Utrecht in the Netherlands. A main hub for cyclists going to the city shopping center and back to its suburbs. It is actually a bridge with a junction on either side. Cars are discouraged to use this bridge. For motorized traffic almost all the streets are cul-de-sac streets. The result is a friendly junction with large numbers of cyclists that weave in a very relaxed way. Note that hardly anyone ever stops. The cycling really is non-stop.

Mistakes are made every now and then (there is even a near collision between a car and a child on a bike in the video) but mostly all traffic flows very well.

And now watch this video explaining about the junction:



Mark continues: A motorway was planned on this very spot in the 1950s and 60s. When building for that road began, there were increasing protests against it and all the demolitions that went with it. The opposition became so strong, that in the 1970s the works were stopped and the road was never finished. Building was stopped just before this area was reached. That is why the bridge stayed as it was.

Since then motorized traffic was diverted and it has decreased so much that even this 1930s bridge became too wide. Half of the bridge is now side walk. The other half is mainly used by bicycles. Cars driving here really have to be in the area.

The unfinished city ring road never really served a purpose. It took the city 30 years to realize that it was best to reverse the situation. After bringing the water back to a place where the road was never built (there the old city moat had been a parking lot for 30 years) it was clear to everybody that this was really what should be done. It took yet another 10 years for the works to start to bring back all the water. Soon the 1970s inner city ring road that should never have been built in the first place will be completely removed.

It could so easily have worked out completely differently...

This type of road often confuses outsiders. It looks initially like any road anywhere else in the world - "shared" equally by drivers and cyclists. Sometimes people who ought to know better but have actually missed the point entirely feel that they have a need to point out that "there are also lots of places when cyclists have to mix it with other traffic" in the Netherlands. However, that is to completely miss the point. Actually, cyclists are nearly 100% segregated from drivers in the Netherlands.

Due to the way that planning of roads works here, this "mixing it" is not on an equal footing at all. Cycle routes are unravelled from driving routes. The second video shows an example. This is is a through road for cyclists, but not a through road for drivers. In fact, drivers are strongly discouraged from using this road, and that's the reason why there are so few in the video. It's not an isolated case, but the norm for most such areas in most cities in this country. Similar results are achieved across the country by using one way systems and bicycle roads.

Cyclists are segregated from the majority of motorists even on roads like this where there are no cycle paths. That is why the majority of cycling happens without interaction with drivers, even though there are 130000 km of road in this country and "only" 35000 km of cycle path. That is how subjective and actual safety is maintained even when the road appears to be open to cars.

I should point out that the priority at a junction like this in the Netherlands works such that everyone, whether driving or cycling, should give way to anyone else, whatever mode of transport they are using, who comes from their right. The speed limit is 30 km/h. And yes, I tried responding directly on Carlton's blog to point out that he'd got the wrong end of the stick, but my reply did not appear there. Explaining such things is a part of what we have tried to do on our study tours.

Preparing for snow

I know it's actually only Autumn at the moment, and we've barely had any frost yet, let alone a single flake of snow, but preparations for the snow and ice in winter have begun.

The video shows what has been happening in Emmen. They've been trying all the equipment out to make sure there are no unpleasant surprises when winter arrives.

As a reminder of what winter is like, and how well these preparations work, take a look at the posts from last winter.

Emmen is the largest city in Drenthe. It's got a larger population than Assen, the capital of the province, where we live.

Oh, and we've got studded tyres if you want them...

Amsterdam video

A nice promotional video from Amsterdam. You'll see a good cross-section of cyclists. It could, of course, be anywhere in the Netherlands.

I first saw this video a while ago, but didn't get around to putting it on the blog. Judy saw it (again) today and said she liked it - good enough reason to put it here in case any of you had not seen it before.

The worst cycle path in Drenthe

Our local paper, the Dagblad van het Noorden recently listed the 12 worst cycle paths in the province of Drenthe (we live in Assen, the capital of Drenthe).

The winner was a recreational cycle path near where we live. While most cycle paths in the Netherlands are wide, smooth and a pleasure to ride on, this one is narrow, not properly surfaced and a bit bumpy. However, it's recreational ! No-one forces you to cycle along it.

Actually, I quite like it. I've ridden along there a few times, and it's a nice change from the normal "perfect" bike paths. It's very much a recreational path.

The winners of this prize, the Natuurmonumenten organisation, are somewhat displeased, as they see it as an old cart track which they made accessible, and which the ANWB then made a part of the local fietsknooppuntennetwork of recreational routes. This caused it to be used more often than it used to be due to signs and maps telling people to use it for recreational trips.

Anyway, here's a short film, which we made back in March when we rode along this path:


See more about normal standards for cycle paths.

Update 2012 - work to improve the surface has made a considerable difference

Thanks to Frits for sending the article - I missed this copy of the paper. The newspaper title reads "Old people fall here in bunches". No doubt a bit of an exaggeration, but it reflects the fact that in this area it's quite normal to come across bunches of old people out in the countryside enjoying riding their bikes. "The worst cycle path in Drenthe" is included on one of our cycling holiday routes :-)

Improving braking efficiency

My Mango velomobile has been a really wonderful thing to ride, but for one thing: the brakes. The Sturmey Archer drum brakes never seemed to quite have the stopping power required. An attempt to stop suddenly was met with a slightly too gradual deceleration and locking the wheels to skid was impossible.

Almost all velomobiles use these same brakes. The Alleweder, Go-One, Milan, Quest, Strada and WAW all also have the same brakes. So do many open recumbent trikes. It's been obvious to me for a while that there was a lot of variation in the performance of the brakes amongst different bikes fitted with these drum brakes. The problem was clearly not inherent in the Sturmey Archer drums themselves as at their best they work very well. I first assumed that the problem was variation in the brakes themselves, and tried changing them, but it made little if any difference. Other people reported improvements by changing the brake cable outers. As a result of this I took a close look at how the cables behaved on my Mango when I pulled the brake lever.

The brake cables on the Mango take the most direct route they could under the circumstances, but relative to the average upright bike it is still quite a circuitous route with a lot of relatively tight bends. The curvature of the cables changes quite noticeably when you pull on the brake lever, and that represents lost braking effort.

Also, these tight bends lead to more friction than normal between the inner and outer cables.

Together, these two things add up to an effect where the inner cable moves a greater distance at the brake lever than at the brake. Much of your effort in pulling on the lever goes into compressing the cable and overcoming friction rather than applying the brakes. They also mean that the springs in the brakes themselves are only just about strong enough to pull the cable back when you let go of the brake lever.

Potentially this could happen on any bike with any type of mechanical brakes, but because cable runs are typically less direct on recumbents than upright bikes, and less direct again on velomobiles vs. open recumbents, I suspect it is more frequently a problem on velomobiles, recumbent trikes and recumbent bikes than on uprights.

A couple of weeks ago I made a change to the brake cables on my Mango which significantly improved this situation. I can stop very quickly with my front wheels skidding. This is how it was achieved:

Good cables are the key to the transformation. I used low compression outer cables to solve the first problem, combined with Teflon coated inner cables for low friction.

Note that while gear shifter outer cable offers low compression it should never be used for brakes. It is constructed differently from brake cable and is not strong in compression. For this reason, it can fail under hard braking, resulting in little or no braking just when you need it.

A tip given to me by a colleague at the Ligfietsgarage a year ago was to remove the rough swarf on new brake cables so that they can rotate more easily within the brake levers. This reduces the chance of the brake cables breaking in the levers, as they often do.

Before and after use of the file.






And the other side...







The wheels are removed with a 5 mm Allen key, giving access to the brake mechanisms. It is a good idea to lubricate the pivots in the mechanisms, but make sure that no oil or grease gets onto the braking surfaces as this will drastically reduce the power of your brakes.

Low compressibility outer cable, with a low friction liner. To make a good job of cutting this you need the proper tool. For the Mango or Quest, the new outer cable needs to be 1.03 m in length.

The easiest way of making sure that the new outer cable takes the same route as the old, including through the hard to reach parts under the bridge, is to use the old inner cable as a guide.

I used a little white grease on the adjusters for the brakes, and also an additional nut to fit against the brake lever for additional rigidity at the lever end. These adjustments should be screwed all the way in. The wheels should then be re-fitted and the brakes adjusted so that they are just free when the brake lever is not pulled. This means that later adjustments can be made, even while riding, if the brake performance drops a little in the first few km after fitting the new cables.

Finally, refit tyres (in this case I have fitted Schwalbe Marathons ready for winter) and pump the tyres up to pressure (the Schwalbe pressure gauge gives an accurate reading of the pressure in your tyres).

Afterwards, it is much easier to pull on the brake lever, with much less obvious friction, the brake lever returns much quicker to being fully "off" when I release it, and the braking is very much improved. I can now lock the front wheels and skid to a halt, stopping in a much shorter distance than I could stop previously. This removes a slight doubt I had with the Mango over whether I would stop in an emergency situation. Here's the evidence:


A slow motion view of the skid. Note how in every frame the label on the tyre is in the same place:


The total list of parts that you need for doing this job is as follows:

• Two lengths of brake cable outer (1.03 m each for Mango or Quest)
• Two Teflon coated inner cables (1700 mm version)
• Four ferrules.

All the parts can be bought individually in our webshop, or we can send you a kit of the parts you need with the brake outer cable already cut to the correct length, at a slightly lower price than buying the parts individually.

Total cost for a Mango or Quest (1.03 m outer cables) is €16.50 + postage (+ 19% tax if you live within the EU). If you've a different bike/trike/velomobile with weak brakes, please check what lengths of cable you require and let me know. I'll add them to the menu.
Read my review of the Sinner Mango Velomobile.