Notes on fitting Dynamo Lighting

So, as is traditional at this time of year, it is with great relief that the artificial tree is packed away. The excesses of the weekend are consigned to history and the ice is a-thawing.  In the mean time, I have fitted dynamo-powered lighting to the Thorn.  Here is what I learnt:

I have already written about the process of selecting light and dynamo.  I have now also ordered a rear light from Bike24, but I will deal with that later.  I ordered a wheel and hub, plus a light, on 21st December and resigned myself to receiving it some time between Christmas and the New Year.  After all, the newspapers have spent days proclaiming with glee about how the country has ground to a halt and deliveries are piling up at sorting offices.  But I had not reckoned on German tenacity and efficiency [Bike24 is an online bike shop based in Dresden, Germany, if you are not already au fait].  On Christmas Eve, I got my parcel and within an hour or so, I had fitted the light and hub / wheel.

On the left, the old front wheel, soon to be usurped by the new dynamo-hub wheel, right.

The box contained one new wheel, with a Mavic 317 rim and a Shimano DH-72 Dynamo Hub.  This is a lovely bit of engineering, with Ultegra-quality bearings and a 3 watt, 6 volt output.  The wheel was beautifully made, and true running. After fitting the tube and tyre to the rim, which incidentally is far more suitable for my kind of riding than the old Mavic 721 rim, which is only built for wide, low-pressure tyres, I fitted the skewer and locked the wheel in place.  Next, I unpacked the light, a Busch and Müller IQ Cyo [175qndi, if you wanna get geeky].

The light is a beautiful, solid item, and obviously German – made.  B&M make the lighting for BMW among others, so you know you’re getting a quality product.  One note – you may find, if you have a Thorn like mine, that the standard-fit bracket fouls against the bottom part of the FSA headset.  If this is the case, then a stout pair of pliers will soon sort it out, although I opted for an old SJS bracket that was in my spares box.  I fixed the light onto the fork crown, and then began the fiddly process of clipping the wires to the fork, being careful to avoid the recently installed Cateye wireless computer [I have cleaned the bike since this picture was taken, you will be reassured to know].

**NOTE: In the picture below you will see two mistakes I initially made.  One, the Cateye sensor is, as Cateye advise, BEHIND the fork.  I have now repositioned it in FRONT of the fork.  If an obstruction got caught up in the spokes, the sensor would have been pushed into the wheel  The second is the wire from the dynamo, which is now routed INSIDE the fork to protect it from damage.**

Having fitted a lavish number of cable clips, the only really irritating part of the install was to insert the bare wire ends into the two little greased connectors on the dynamo hub.  This seems to be a process that has to be repeated every time the front wheel is removed, which I shall have to learn to deal with.  Then, I gave the wheel a quick spin and, behold, light issued from the small black pod.

I lost no time in getting wrapped up in my thermals, and then hitting the road for a ride.  I used the light as a day light running light, and could barely wait until darkness descended so I could witness its legendary output [I chose the 60 lux version, which throws the light beam further forward that the 40 lux version of the same light, which simply has an altered beam pattern designed for slower riding].

A fuller report of the light’s qualities and the rides I have done so far with it will be along shortly.