dcrowell

I have a B&M IQ Cyo headlight with a wired tailight powered from my SON hub. I really like it, but I'd like to run two headlights.

If I wire them in parallel it *should* work, but I'm worried about what speed I'd have to go to hit full brightness.

Has anyone done this? I'm running the standard SON28 hub on a 700c wheel. If I can hit full brightness at 10mph or less I'll be happy.

Richard Cranium

Your lights may never get to full brightness. The "brightness" of each light is dependent on the current it draws which in some part is dependent on the resistance of the circuit with both lights wired and switched on.

I don't think there is much "extra" power in generators - isn't it a six watt device?

pdlamb

I'd kick this question over to Peter White. It was apparently common back in the dark ages (before LED headlights) to run two halogen lights in parallel, with a switch to turn the second one on when you exceeded a certain speed (12 mph?). I don't know if you could do this with LEDs like the IQ Cyo.

dcrowell

The "rating" is 3W, however this is reached at quite a low speed. The hub has no regulation, that's left to the lights. Most decent hubs can output substantially more at higher speeds.

My understanding is that Peter White will poo-poo the idea and not even research it (someone has asked). He says one IQ Cyo is enough light. Some of the old halogen lights were specifically made to run as secondary lights... that idea hasn't made it to modern LED lights, hence wiring in parallel.

I was hoping someone had tried it. I have another bike I need to outfit with dyno-lights, so I'll have two lights in the house to experiment with... although it'll be a few months.

znomit

Cyo is around 2W output. Bit of headroom there.
There are brighter dyno lights than the cyo.
Get a supernova if you really need more... Or get a battery light to supplement for those odd sections when the cyo is not enough.

DogBoy

On a 700c wheel I hit "bright enough" with a single light somewhere around 3 mph. I assume that both lights will be "bright enough" at around 6 mph. I have also thought about this, and considered trying it last spring, but then summer came and I didn't ride much at night anymore. Now that I will be riding to work every morning in the dark, I'm toying with it again. I'll post back if I try it with some stats on brightness and let you know if I'm going to keep the setup. It'll probably be a few weeks before I get to it.

PaulRivers

I don't believe the Supernova is significantly brighter than the Cyo. And getting a battery light would obviously be completely the opposite of the point of owning a dynamo light.

With such a shaped beam I would wonder how much benefit one would get out of having 2 Cyo's though...

dcrowell

One would be the nearfield version... the other not.

pdlamb

Ooooh - kay.

I'll go out on a limb and make a prediction: if you do this you'll find there's an enormously bright spot where the two overlap that leaves you with night-blindness such that you can't see anything in the near field nor in the far field.

But do report back and let us now how it works when you do try it, please?

PaulRivers

+1, I would...wonder if that would end up being the case...and am really curious if you do do it what you think of the results...

I'm not saying anything for sure, just my thoughts at the moment. :-) If I personally was going to hook up 2, I would be highly tempted for the second one to be a supernova e3 because it would put some light on the ground to the sides (and also in the dark spot between the bike and the Cyo beam, though that doesn't bother me personally).

znomit

Clever cycles can probably advise:

https://clevercycles.com/products/com...ator-lighting/

dcrowell

That's beautiful. Apparently it does work. I still need to figure out how to mount them, as my bikes don't have those rack braze-ons near the top like that.

DogBoy

I did it with mine this weekend. It does work. I mounted one on the fork crown and the other on a crono nob with the PWC adjustment to a flight-deck computer mount. I hit full bright around 5 mph...or at least that's when I can't tell it gets any brighter from there.

dcrowell

Great! I'm glad you were the guinea pig.

I can actually have a setup like the photo above now as I'm the proud owner of a new (to me) Big Dummy.

hybridbkrdr

Wow, do you have any instructions on how to split the wires and all that? Do you still have to replace the connecors when installing a Lumotec Cyo? I saw a video on Youtube and it showed someone modifying the ends of the connector.

Could anyone post a photo/video of the beam with two lights?

fietsbob

E6 halogen run in series, the secondary is wired different , on or through.. ,
those you do have to be moving at a good clip to gain the benefit of the second light,
it is there to not out run your lights, on Brevets and such..




Alternators have a fixed amplitude , the sine wave only goes so high and low,
on an oscilloscope , but the frequency is increased with speed.

dcrowell

You would just run the two Cyo is parallel - meaning connect each to the hub. It would probably require crimping or soldering the wires from each on the connectors.

hybridbkrdr

I just thought of something though. There may be a double adapter where you connect the light to the dynamo hub, unless I'm wrong.

EDIT: Whoops, I just searched and now I don't think it exists.

CaptCarrot

Just crimp up some y cables using the same miniature spade terminals they Cyo uses.