Lenses for Road Riding

[gaetank]

I am in the process of building myself a single CREE XR-E bike light inside a 1" aluminum tube. I have never owed or used high power 'to see' bike lights (as opposed 'to be seen lights') so I don't have any actual experience. I have a CRS-RS lens (6 degree FWHM) and a CRS-M lens (14 degrees FWHM) an am trying to decide which to use. Anyone have any suggestions as to which might be better for road riding? I plan to use it for commuting as well as recreational night riding.

Gaetan

 

[znomit]

For road the narrow one will probably be ok, it will concentrate the light a lot more than the wide (around 5x) and you will be able to see a lot further.
Its hard to judge without seeing beamshots, you want a bright area lighting up the lane ahead but you also want a small amount of light to see to the sides, how much is personal preference. If you can, try both.

 

[HEY HEY ITS HENDO]

Hey gaetank :thumbsup::welcome::wave:
.........i`ve found that on the dead straight bits a narrow beam is good but,
on the bends and twisty`s a wider beam is way better ...
so my vote goes to 14 degree, best for both !

 

[waiwak]

I do almost all of my night riding on a paved trail which is mostly straight, but with a few curves. I've ridden the trail enough times that I know it quite well. That said, you'll want throw AND spill. You'll need throw so you can see and avoid someone on foot before you run into them, and you'll need spill so you can see and avoid low hanging branches above you, and potholes below you.

 

[n4zou]

A Luxeon Fraen Elliptical Beam Lens With Holder works perfectly with a Seoul Semiconductors Z-Power LED Emitter (U-bin). The beam pattern is perfect for road use. Wide enough to illuminate curves and narrow vertical width so there is no wasted light. I use it with a dynamo so no batteries are required or wanted. Light output is more than just adequate. I've had vehicles flash their high beams at me in an attempt to get me to dim my light. With batteries and higher current drive even more light will be produced. Here are the links.
http://www.luxeonstar.com/item.php?id=462&link_str=121::125&partno=FHS-HEB1-LL01-H

http://www.dealextreme.com/details.dx/sku.1445

 

[ifor powell]

OK I have tested all the squar lenses. I have a double Led setup on my road bike and have gone for two of the difuse lenses. My road cycleing is mainly around town and the I think the diffuse is beter for being seen at an angle. I would not go for the RS as that's not got much spill. With the double setup I still get plenty of light in the dark lanes on the flat. I would problby think twice if I did any big decents on dark lanes though and probobly go for 2 smouth spots or a combination.

Ifor

 

[gaetank]

Excellent! Thanks for your responses! I think i'll probably go with the CRS-M lens. Depending on how it works, I may build a dual later on, or maybe add another single. I have a XR-E Q5 from deal extreme and an R2 from from cutter so i'll mostly likely be adding to it in the future.

Thanks again!

Gaetan

 

[Zero_Enigma]

I find 5 degree spot to be a good beam for riding on the road and back that up with a 15 degree for spill and to give a wider down range lighting. I use L2 optics ( www.luxeoncanada.com is where I got mine from) which can be found at www.ledsupply.com .

The optics work and fix easy on the SSC P4 from DealExtreme. Also I would recommend either http://www.dealextreme.com/details.dx/sku.3256 single mode regulated driver or http://www.dealextreme.com/details.dx/sku.7425 5-mode regulated driver. You can use any toggle/pushbutton switch that is a on/off switch to cycle the modes. Each time you turn off the light and turn it back on in less then 2 seconds time you advance up to the next mode.

Because both drivers offer you a wide 3.6v-9v/3.6v-8.4v you can use a 4 or 6AA battery pack or heck in a bind stick a 9v battery in and it'll run.

I have used both drivers and they are good bang for buck. I have tested both drivers as well during the fall season but once it warms up I can begin my spring/summer testing to see how the lights hold up.

The 5-mode driver I have tested with 6xAA Duracell 2650mAh NIMH batteries hot off the charger 8.5v on high mode for 4hrs runtime powering 2 x Cree Q5 LED's on a chunky brick sized heatsink. Not bad if I say so myself.