Mountain Bike Reviews Forum banner
1 - 14 of 14 Posts

Registered
Joined
9 Posts
Discussion Starter · #1 ·
I currently use a mr16 20w halogen light with a 12v 6500ah li-ion battery & was looking to build my own light for both brightness & longer run time.

I have been lurking and researching on this site for several days & kind of have an idea of what I want. I have access to a metal working shop so they fabrication & mounting should not be a problem. I have a few questions about the electronics though.

I was looking at using one of Cutter's 3 or 4 led xp-g pcb's. I will research the optics later. (Any suggestions for a nice tight beam ;) I will probably use a buckpuck 1000mah or
b2flex for a regulator. Could I power 4 led's at 12v at 1500mah with this. Or would a 3 led system be better? I want the brightest system possible. This will be mouned on the handlebars of a Jamis Durango 2.0
 

A waste of time it is is
Joined
6,076 Posts
harvman, from my understanding if its a li-ion battery its not 12v and if it is 12v then its not li-ion but probably ni-mh?

You need to clarify exactly what it is if you wish to use this battery because the b2flex requires up to 1.7v + the led vf . assuming a vf of about 3.3v for each led, that gives you 9.9v total plus 1.7v for the driver gives you 11.6v. If it is a 12v battery you'll be fine till the battery starts to drain down. If its a 11.1v li-ion then you'll be out of regulation for most of the battery discharge, if its 14.8v then you're good to go.

If you have a voltage regulated battery similar to these from batteryspace then again, 3 leds will be OK but 4 won't.

Just to confuse the issue you could run 4 from a 12v battery but you would have to run 2 parallel strings of 2 leds. Problem with this is they'll only see 750mA each, not the max 1500mA
 

Registered
Joined
3,916 Posts
harvman5 said:
I was looking at using one of Cutter's 3 or 4 led xp-g pcb's. I will research the optics later. (Any suggestions for a nice tight beam ;)
Based on your request for a nice tight beam using one of Cutter's PCBs you'll need to go with a triple and the Cute SS optic. The quad may put out more raw light but it won't be tight.
 

Registered
Joined
489 Posts
I'd go for 4x XP-G and maxflex with this battery pack. Optics would be 2x regina for throw and 2x carclo 10417 for flood. With 3up or 4up boards you get very limited with optics choice, using separate pcbs gives you much more freedom in building your favorite beam pattern.
 

A waste of time it is is
Joined
6,076 Posts
Toaster79 said:
I'd go for 4x XP-G and maxflex with this battery pack. Optics would be 2x regina for throw and 2x carclo 10417 for flood. With 3up or 4up boards you get very limited with optics choice, using separate pcbs gives you much more freedom in building your favorite beam pattern.
I would stick with just regina's, he wants a tight beam. Not sure about run time with that set up though
 

Registered
Joined
6,455 Posts
Since it sounded as though he wanted to use either a triple or quad board, I would recommend a quad XP-E in either R2 or R3 if you can find an R3 board(?) Coupled with a good narrow quad optic that could be a good way to go. It won't be as bright as a quad XP-G but the XP-E's have more punch and with four you should have all the light you need on the bars. Trying to run those at 1500ma might not be a good idea though. With all four leds so close together the heat would likely turn the emitters to toast in no time flat. In that configuration, if it were me, I'd keep the max to within 1000ma.

Now if you decide not to use a single multi-led board....well then that changes the whole game..;)
 

Registered
Joined
3,916 Posts
Cat-man-do said:
a good narrow quad optic
Doesn't exist in my experience, at least with XPGs. I have been tempted to try and cut the corners off 4 Reginas to fit the XPG quads that I have. $70 worth of emitters that aren't worth building a housing for unless some tighter optic comes out:mad:
 

Registered
Joined
6,455 Posts
Vancbiker said:
Doesn't exist in my experience, at least with XPGs. I have been tempted to try and cut the corners off 4 Reginas to fit the XPG quads that I have. $70 worth of emitters that aren't worth building a housing for unless some tighter optic comes out:mad:
Yes, I agree. That is why I recommended it be done with XP-E's. Though I've not seen an actual direct comparison, others have commented that the throw with XP-E's is better. I just figured that would also translate out to better throw when used with a multi-led optic. No, it might not satisfy everyone but if it does throw better it would be the better way to go the way I look at it ( if using a multi-led board that is ).

Note: Kerry from K-Lite has recommended the XP-E's for a tighter beam pattern on his triples and I believe WeLight commented ( somewhere ) about the XP-E's being better for throw ( on multi-led boards )...just saying. If I'm wrong about that I'm sure someone else will correct me.
 

Registered
Joined
2,374 Posts
there are some beamshots on quazzles Lux-RC site of triple XP-E, XP-E HEW and XP-G w/ narrow Carclo optics and the plain XP-E does have a much more defined hotspot with less spill. Seems to reflect what a lot of people have said on here in the past, so I think it's pretty indicative.
 

Registered
Joined
9 Posts
Discussion Starter · #11 ·
So far from my research on this site & your input this is my build plan:

Battery is 11.1v 6500mah li-lon (I may buy one of those 14.8v Lipo r/c batteries on ebay.)
4up xp-g pcb from either Ledtech.de or Cutter (Which is better for shipping to the USA?)
Cree GT4 23 degree optic & Cute-4 9 degree optic for the xr-e (will try them both out)
I saw some impressive beamshots on this site of the Cute-4 used on xp-g's
32mm round heatsink for the board
Maxflex5 boost controller

A few things I havent decided on yet include the enclosure (probably a small weatherproof aluminum box from Hammond Manufacturing or something similar on ebay) & switch. I intend on using automotive weather pak connections & cable sleeves.

I settled on using an array vs single leds because it just seems easier for a beginner to build a very bright light.

Does anyone have a recommendatiion on a switch for the Maxflex?
Has anyone in the USA ordered from ledtech.de & how was the service? I don't see them mentioned often here.
 

Registered
Joined
3,062 Posts
harvman5

forget the GT4. for throw with xpgs IMHO it is not a good optic.

you want an easy build. with throw have a look at this thread for a self build kit using the new XMLs

http://www.singletrackworld.com/forum/topic/diy-900-lumen-and-1800-lumen-kits

with the Laura optics you will get a very bright easy to build light it will need a bit of filing and sanding. if you want shiny and smooth
 
1 - 14 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top