vosyer

I just bought a new Soubitez rear generator the type that attaches where a kick stand might go and a german union light. My intent was to this on the touring bike that I am building up. Anyone have experience with this type set up or is it just passe with new technology. I don't intend to do much night riding, but I wanted a backup just in case and batteries didn't appeal to me.

MichaelW

Bottom bracket generators are quite rare but tourists do use them. A useful trick is to fit a cable to the switch, operated by the friction gear lever on the seat-tube or downtube. Clamp-on levers can be found in the old parts bin of a good bike shop.

I use a bottle dynamo for evening trips into town or foggy days.
The old 1970s Union lamp has been superceded by modern computer-designed optics such as Lumotec.

Juha

+1 to Lumotec lamps. I've been riding a couple of winters now with a B&M bottle dynamo and the Lumotec Oval -light. I am pleased.

--J

jakub.ner

Really? A bottle dynamo during the winter in Finland? Does it work because it's so cold that you don't have moisture issues or does it work because the dynamo is of good quality? I've tried a cheap bottle dynamo in the winter here in Canada and it just slipped, so I used batteries. But I've just bought three cheapie bottle dyanmos for exactly the same reasons as the OP, just in case: commuting and long distance.

Lotum

You're quite right--arctic/semi-arctic winters and bottle dynamos don't mix. If you want to see (in addition to not having slipping probs), hub dynamos are the way to go. Battery-powered LED lights are also ok, if you want merely to be seen.

MichaelW

Have you tried expensive bottle dynamos?
The biggest problem with bottle dynamos is the mounting system. They really need a solid braze-on tabe to work at peak efficiency. Clamp-on brackets are useless and the source of most of the problems.
A hub dynamo is better for regular use, esp in bad conditions but sidewall dynamos are great for fit-and-forget occasional use on tours.

lighthorse@eart

Why? Unless you are a commuter who must ride in the city at night, why do you need lights?

MichaelW

On tour, you can run into fog, mist or mountain-top cloud. In the evening, a campsite or hostel is often a short bike ride away from the local pub or restaurant.
On winter rides in more northerly latitudes dusk can start round 3:00 pm.

Juha

jacub.ner and Lotum, it does work. Like Michael W explained, a good bottle dynamo with a proper mounting bracket will have little slipping issues. After tweaking around with adjustments and spring tension for a couple of first rides, I have had none in two winter's time.

I have several rechargeable NiMH battery based lights, both LEDs and halogen. NiMHs don't work too well in the cold, so I decided to try dynamo for winter. I did not want anything fancy or expensive or complicated, so I chose the basic Dymotec 6 bottle dynamo and Lumotec light. I was mostly worried about the amount of light, as the Lumotec has a seemingly feeble 3W lamp (actually, I'm still running the factory installed 2,4W). By now I'm convinced, the light is good for commuting and running errands, because the lense and reflector design and manufacture quality are exceptionally good.

I will upgrade to a hub dynamo, though. It has better efficiency and lower drag when in use. I need the dynamo on almost every winter ride, as we only get a couple of hours of daylight up here. Therefore for me the one advantage bottle dynamo has over hub dynamo (zero drag when not in use) is not so significant. If had less frequent use for the thing, I would not bother with the new front wheel and all.

--J

jakub.ner

Great! What is a good mount for a dynamo then? The OP discusses a dynamo that attaches to where the kick stand attaches. That sounds solid but old skule. How do good (read German?) dynamos attach? You guys mentioned braze ons. Are these the rack braze ons?

vosyer

I am putting the dynamo where there the kick stand goes, but the old school 18 year old Koga Miyata that this is going to has braze on's to attach a rear wheel friction dynamo. First I had ever seen - the braze is just below where the brakes attach. I assume this is common on European touring bikes, but not in the State's

Juha

Re: a good dynamo holder. This is what I use, it mounts to either front or rear brake fittings.

https://www.roseversand.de/output/con...0&detail2=3468

--J