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Carbon8er
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1,407 Posts
Discussion Starter #1 (Edited)
I just got the new DX P7 bike light.
Tore it down and took some close up pics of the guts.

There are few things worth noting.

The P7 is not screwed down.
There is no heat sink grease under the P7
There are alumnium shavings big enough to short something inside the electronics cavity.
The red wire leading to the P7 just fell off the board, it was not soldered properly
Make sure you tear them down and have a look around inside.

The housing looks nice.
The battery and trail tech type connectors look good enough to me.
The charger is pretty light, hopefully it holds up.
The reflector is very short and wide which may make the beam very wide angle. Have to see later when it gets dark.

Bigger pics here.
https://www.el34world.com/Misc/bike/BikesLights35.htm





 

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Carbon8er
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1,407 Posts
Discussion Starter #3 (Edited)
Will do, I may be only able to do some off the porch tonight.
It started raining again a while ago.

Been trying to get out and do some beam shots on several lights for a couple days now but the weather is not cooperating.

I'll post them later tonight if all goes well.

Bigger pics here. Hit refresh to make sure you get the most recent page changes.
https://www.el34world.com/Misc/bike/BikesLights35.htm


Here's a shot of some of the imrovements as I am assembling it again.


see ya
 

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Carbon8er
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1,407 Posts
Discussion Starter #4
Ok, the rain stopped long enough to run out into the woods next to my house. and shoot some beam shots.

I set up four P7 lights on a tripod.

3 of the P7's have a 1.4 amp Low setting and a 2.8 amp High setting.

The 4th P7 is the DX bike light above. The text on the Dx2 light is not correct. Not sure what the actual current is on this light yet. I'll have to measure the Dx2 bike light current for the High and Low settings.

I'll set up a web page with the results when I get to work tomorow, I don't have access to my web editor right now.

For now, I'll just show you one of my P7 lights and the DX bike light.
I actually took a picture of all 4 P7's on at the same time also.
Looks like the woods is on fire. :D

That hump in the background is about 50+ feet away.













 

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I like bloody ankles
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139 Posts
big difference

were all of the lights running off the same battery pack ?

in the "all on" pic, gives you an idea of what too much light would be like.
 

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mtbr member
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890 Posts
Seems strange that they decided to drill a hole right under the LED on the aluminum slug it sits on.

Thanks for the beamshots. It looks like the tints are different, I actually like the DX light's tint more for color (WG I think) where the Hoffman looks like a WC tint and is brighter. I think that the beam pattern may also cause the DX light to look like a poorer performer in the shots. The Hoffman light looks more floody than the DX. It also looks like it is not aimed at the same spot since the DX light is pointed more squarely at the mound, while the other is pointed closer to the foreground.

What was the live impression of the DX light - good, bad or just different?

Forgot to ask, but were these all taken with manual exposure, and the same settings?
 

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Registered
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344 Posts
Hey EL34 thanks for the review and the pics!!

Isn't the high mode on the DX2 P7 only 2.4A???

It seems that the Dx2 P7 has a much warmer tint than the Hoffman and also puts out a litte less light!!!

Edit: damn - i was too slow :eekster:
 

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Carbon8er
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1,407 Posts
Discussion Starter #10
were all of the lights running off the same battery pack ?
No, each light had it's own 3.6 volt 4x18650 battery pack.
The DX2 light has it's own pack also.

in the "all on" pic, gives you an idea of what too much light would be like.
Yeah, that was a silly shot. If I ran 3 P7's, I would aim two on the bars out to the sides just a tiny bit to spead out the beams and the helmet light would be the third one.

Seems strange that they decided to drill a hole right under the LED on the aluminum slug it sits on.
Yeah, I don't understand that either.

Thanks for the beamshots. It looks like the tints are different
The P7's are all from DX and look the same to me. The reflectors have completly different shapes. I'll post the reflector shapes for all four lights later.

What was the live impression of the DX light - good, bad or just different?
Not bad at all. It seems not as bright to me, could be the short stubby refelctor and the supposed 2.4 amps max current?
I may leave it alone or I may do some more modding on it.
The low setting was very very low. I think the low should be a bit higher.
The flashing mode is cool, but not very useful to me personally.

Forgot to ask, but were these all taken with manual exposure, and the same settings?
Yes, F4 at about 5 seconds. It was very dark in the woods and the leaves were sucking up the light like a vacuum.


Just getting up and having my coffee. I'll be at work soon where I can post pics of all four P7 lights I tested. I'll inset a small pic of each light in one corner and a pic of the reflector in the other corner. The reflectors are diffent in 3 of the lights and seems to make a big difference in the beam spread. All four lights itested had the same P7 from DX.
The only difference in the P7's is that the DX bike light is not running at the full 2.8 amps like othe other 3 P7 lights were..

Be back later
 

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Carbon8er
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1,407 Posts
Discussion Starter #11 (Edited)
I just set up a beam shot page with lots more pics and info.
I show the reflectors used in each light

Actually, the Marwi conversion I did was my favorite light.
Even though it has the same LED, same reflector and same electronics as my home brew P7
Hard to say why it looked brighter.
The only difference was the batteries used in each light.
Looks like I aimed the Marwi a bit lower, which would make it look different.

The actual distance out to that mound was 63 ft or 19.2 meters.
A bit further than I guessed in the dark last night.

Here's the link to the beam shot page.
https://www.el34world.com/Misc/bike/BeamShots1.htm







 

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Carbon8er
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1,407 Posts
Discussion Starter #12
Well, in an attempt to get a current reading on High and Low on the DX bike light, something went wrong on the circuit board.

I was able to get two current readings by placing my mutimeter between the battery and the light.

I got 1.4 amps on high and .5 amps on low.
That could explain why it looked so dim in the beam shots last night.

That reading did not seem right and so I took the light apart again and was going to insert my meter between LED and the circuit board to read the actual current flowing to the P7.

As soon as I unsoldered the - on the LED and inserted my meter, the P7 went on real bright, and then it died down to almost nothing.

It's not the P7 itself because I hooked up another P7, same thing.
The circuit board green LED lights up and the battery is reading 8.5 volts.

https://www.el34world.com/Misc/bike/images/IMG_1385_small.jpg

I looked down under the coil on the board and saw what looked like more of the tiny aluminum thread shavings.
I removed the coil and had a look.
There were a couple pieces of aluminum under the coil.
I sprayed the board real good with electronics cleaner and intstalled the wire coil again .No good, same thing.

The soldering on this board is pretty sloppy. There are several blobs on the IC chip legs that look like they are touching more than one leg.
Hard to say what happened, but the light is dead. :mad:

Seems like a great time to go ahead and convert it to my 1.4 amp/2.8 amp/clicky switch mod.
Re-configure the battery pack for 3.6 volts.
Use my good chargers from now on to charge the battery pack.
 

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mtbr member
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890 Posts
That sucks, but it was probably bound to happen sooner or later based on your description of the board and the poorly finished interior of the case.

Do you know what the diameter is for the driver?

What seems odd to me about the beamshots is that the Hoffman P7 appears to have a deeper and narrower reflector, and the beam looks more floody than the other, but the DX P7 reflector looks like it is much wider and it's beam is more focused. I had thought that the deeper, narrower reflectors were usually better throwers. I think the beam on the Hoffman P7 is much better overall though.
 

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Carbon8er
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1,407 Posts
Discussion Starter #14
Do you know what the diameter is for the driver?
The board is 21.75mm diameter.

I like the Marwi and the Hoffman.
yeah, isn't that weird, same exact reflector, same exact electronics, Same exact P7.
Different battery packs, but both packs are brand new.

Could have been how they were aimed?

I just thought about this though, the Hoffman had a real short lead on it and so I made an Anderson PowerPole extention cord about 2 feet long and patched it in between the battery and the light to get more length.

I wonder if those extra connections had anything to do with it?

Anywho, I have the DX bike light tore down.
Not sure I have any time today to mess with it, but I'll do my clicky mod to it just for grins and see how that goes.

I could always sell the Dx Battery pack, Dx charger and Trail tech connector cords to someone who may be able to use them.

I'll make my own 4x18650 battery pack instead of tearing apart the DX pack.
 

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I've just received my light from DX, I unscrewed the top of the light and it looks different to yours, possibly a different revision? Can you explain how to fully dissemble the light as I don't want to break it.
 
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