Planning on mounting a dyno (Shutter Precision)-powered light on the bottom of my front rack. Will be riding in total darkness quite a bit (brevets and Seattle winter commutes), so lighting the ground is as important is being seen.

Any suggestions?

Thanks!

Cormac

For randonneuring, I would go with an Edelux II or an IQ-X.

Tough to beat the performance and value of the B&M lights. My 80 lux Cyo Senso Premium with its shaped beam is a total game changer. The shaped beam allows control over where the light is cast. Follow the instructions and you'll enjoy riding with an amazing field of view without blinding oncoming traffic. B&M has a 100 lux (IQ-X?) which, considering how nice the 80 lux performs, must be insanely great. I also recommend B&M taillights.


-Kedosto

There isn't nearly the room you think there is under your front rack. Adjacent to the rack might work but leaves the light either ripe for getting hit or one side of the bike blind. Mounting at the axle leaves the bike susceptible to splashes and throws the light too horizontal. B&M specifically say not to mount the light at the axle. Also they say that a dynamo light mounted mounted upside down won't have good optics & is likely to fill with water. Between the fork crown and the handlebars is best.

I am pleased with the B&M Lumotec IQ-X it's 100 lumens, but has a narrower throw & weaker plastic mount than the Luxos U. I think the driven led's are likely the same but The Luxos U IQ-2 is nominally 70 lumen, largely on account of the wider light distribution, thus lower light "density". The Luxos U IQ-2 will do 100 lumens for short periods of time until the internal cache battery depleats. The Luxos U IQ-2 also has a remote switch I don't like because the housing broke after 50 miles, & the switch seems susceptable to water intrusion & has to be mounted somewhere. So yet another wire.

The problem. with dynamo lights rests purely on the number of electrons you have in supply. Bright & focused or less bright & distributed. Either light I mention is plenty bright enough to ride by, but my preference is the IQ-X due to it's simplicity.

Agreed.

I've seen a "mount" that'll hole one of these on a rack, though I can't find a link now. It's basically just an arc of sheet metal, presumably fairly stout, with a hole in either end. One bolt holds it to the rack, and the other holds the light to the mount offset from the rack so you get clearance. IIRC you could buy it for $10-15, although an afternoon in the garage with a Dremel and some aluminum sheet stock might be cheaper. It looked fairly elegant, though I never got a round tuit to mount my troubled light like that. Anyone remember where that was?

E Delux body & mount is Aluminum, lens Glass; B&M, plastic .. Tab, most of body* and Lens
I have the B&M Eyc Senso T on my Brompton, Fork Crown Closer to the ground so seems brighter..

* top of body is aluminum for LED heat sink dissipation..


In LBS, had more than 1 B&M Luxos U* arrive at tour's end, broken off , mounted on the front rack of tour bikes.. getting to the coast..

getting a rack fabricated with a light guard?


* that one includes a USB output..








...

All very good points. No upside down mounting. No sideways mounting. No axle level mounting. I originally mounted my B&M off the front of my porteur style front rack. It stuck out too far for practical use and I got tired of knocking it on things. It was only a matter of time before I broke it. I could have mounted it back at the fork crown, but with the porteur rack anything placed on the rack blocks the headlight. I ditched the rack and went with a Tubus Duo set, and mounted the light at the fork crown. The world is now a well-lit place.

The mounting arms on my B&M headlights are stainless steel and are very stout. It would be a shame if they cheaped out with plastic mounts on the new models.

-Kedosto

With my Koga WTR (short travel) Suspension fork, I used a B&M Nylon Mount on my Schmidt e6 and kept it, for the E deluxe ... its been fine for 10+ years..

so Best , for clarity, if you specify Which Plastic ...

The casing of the B&M headlight is not ductile like Nylons.. its more prone to crack , and have things like the mounting tab break off when hit..

My Eyc is well protected, under my Brompton front bag, use a stamped from Stainless steel sheet metal mount on it (Schmidt made)







....

I am using an IQ-X and love it. I have several trail sections through the forest which are in the pitch black and this little headlight provides a lot of light. I however did not use the standard plastic bracket but used a more sturdy metal bracket.

Another happy IQ-X user. Great bright lighting pattern and flexibility in mounting (i.e. the mounting strap can be rotated around the light body for any orientation). Yes the mounting strap (sleeve?) is nylon but seems to be pretty robust. If it worries you, you could fabricate a metal one with not much trouble.

Totally agree. I am also using an 80 lux Cyo Premium for randonneuring and am very satisfied with it. Like you, I can only assume that the Edelux and the IQ-X are even better. I went with the SON widebody deluxe hub and B&M Toplight in the back and couldn't be happier.

I also vote for the 80 lux Cyo Premium.

What rack are you using? Do you have fenders? If so, what fenders? Here are a couple ways I have that light mounted:

I'd get an upside-down Edelux ii, but I got a great price on a right-side up one so I have it mounted with the Nitto lamp holder #6. I also looked at the soma wingman, but it seemed like a bit too much.

+1 on the Cyo Premium.

B&M IQ-X is the brightest light and offers much bang for the buck.
bumm.de/en/products/dynamo-scheinwerfer/parent/164/produkt/164rtsndi-01-schwarz-164rtsndi-silber.html?

Taillight:
bumm.de/en/products/akku-batterie-rucklichter/parent/323.html?
spanninga.com/en/product/pimento/

Mounting options:
bumm.de/en/products/mehr/gruppe/Mounting%20brackets.html
bikeforums.net/electronics-lighting-gadgets/1126857-minoura-spacer-light-gadget-mount-di-light-fender-hole-mount.html

Moved from Commuting

You can mount the IQ-X upside down too.

I assume you already know this, but just in case you don't, most lights have a vent hole in the bottom and that is one reason (besides light beam) that other posters are saying do not mount it upside down, as rain water can get into the light if it is upside down. But not yet mentioned is the potential for tire spray if you do not run fenders. So, think about where your tire spray is when you decide where to mount the light so that the tire spray does not get into the light casing.