Electronics, Lighting, & Gadgets - Dual MTE P7s modded for use with battery pack

Hello,
I just thought I'd show my new light setup which looks to be very good for the amount of money invested. It consists of:
(2) MTE 5-mode P-7s modded to run on external power
(6) 18650 Trustfire 2500mAh protected batteries in parallel
(2) Fenix light mounts superglued on the 90 degree position
(1) Viewpoint spacebar
Also anderson power pole connectors and wiring for the connection.

Beamshots coming soon, I haven't really aimed it properly or anything yet either and the battery pack needs to be dressed up abit.

http://img.photobucket.com/albums/v320/Jam_Master_J/light1.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/light2.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/light3.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/light4.jpg

Ride Impressions:
I took the bike out for a quick 25km ride that covered many lighting conditions. First the ride started at my home out in the country with potholed roads and very dark. The lights worked great here, I ran both lights on high just to really get the best look at the potholes and cracks in the road. Throw was not a problem at all, I could see very far ahead so 25 km/h was just like during the day. After about 10km I got to a new area lit with streetlights periodically, this was a hard test but with both lights on high I was able to push through that light and still have useable light. Then I pulled into a MUP that is surrounded by trees/bush, wow, this is where a floody light dominates! I could see everything, everything. I pulled it back to just one light and was still seeing everything I could possibly need. And then for a little I got to ride some smooth, straight roads so I went one light high and one medium, this grants the most uniform beam when the high is aimed up more.

Conclusion: Very happy:) The light output is great (I've had cars overtake me and my lights were not being washed out at all), the beam is great with one aimed low and one at medium range and the flexibility of 2 lights lets you find the ideal setup for almost all scenarios.

Let me know what you think.

I like the bike.
Where do you have the battery pack?

Thanks, its wrapped up in a green shirt on the back rack just for testing. It has a quick disconnect so it can be removed easily for charging. It'll be zip tied to the rack for short runs and put in my panniers when I have them on.

Enjoy your rides.
Looking forward to More pics.
Thanks for the post

Can you post close-ups of how the flashlights were modded to accept power from the pack?

I have the same sort of setup with dual P7s (no external batt like yours however). works best if you use one on high and one on medium.

how waterproof are the cable leads coming out of the light?
I know mine were rain proof even in this weekend's downpour.

Looks nice. Shouldn't have trouble lighting up the road with that setup.

glad someone tried this!!!

Can you post close-ups of how the flashlights were modded to accept power from the pack?

It may be a bit difficult to open the lights back up again since I don't want to twist those wires too many times and fatique them. But heres what I did at least and I'll get some close ups of the entrance at least:

1) Remove the battery and disassemble the light (remove tail cap, head, unscrew pill/heatsink from the body). Note it is a little hard to remove the heatsink and pill, I just gently anchored the brass part in a small vice with rubber edges and turned the body and it came right off.

2) Drill a hole in the body, the location isn't extremely important but I put it on one of the flat edges (like the MTE logo is). I also installed a rubber grommet to hopefully water proof the entrance.

3) Route two wires into that hole and route one of them to the head (this will be your positive connection) and one to the tail cap area (for negative).

4) For the positive connection, pull some slack in the positive wire to work with, then solder that wire to the base of the spring on the brass heatsink (which is not screwed in the body at this point). I feel the base is more stable than the end of the spring and there is already some solder there to give you a good point to connect to.

5) For negative, repeat but for the tail cap. In this case however the base of the spring is not easy to reach so wrap the wire around the end of the spring and solder it.

6) At this point, if you have a multimeter, test and make sure there is no continuity between the positive and negative wires just to be sure.

7) Reassemble the light, try not to twist the wires too badly when doing this but it seems inevitable so use stranded wire not solid core.

8) Do whatever you want with the other ends, I put them on power pole connectors so they can be removed from the bike.


You want to keep resistance as low as possible, there is enough current flowing here that even a small amount of resistance can lower the performance in high modes where the lights would be pulling around 5 amps. If you use disconnects, I like the power pole style and make sure you get a strong crimped connection. The wire should be of reasonable gauge, I used 14 awg for the long run and that seems good. I wouldn't go smaller than 16awg. For the short connections to the lights at the end I used 20awg silver plated copper to each light (remember these only carry half the current and are shorter so its not as important to be big). Make sure your soldered joints are strong, any resistance is going to bleed energy.

I have the same sort of setup with dual P7s (no external batt like yours however). works best if you use one on high and one on medium.

how waterproof are the cable leads coming out of the light?
I know mine were rain proof even in this weekend's downpour.

I agree, one on medium up close and one high aimed further is quite good. I run both on high when there are street lights so it will cut through. The leads seem quite waterproof since I sealed them with grommets but I'm going to keep an eye on it for sure.

This gives me a great idea. My Soho that was converted to a Single Speed has internal cable routing. I could fashion something like this and run the wires through the frame where the rear derailleur cable used to be and mounting a battery pack below the bottle cage mounts (or even attached to both to the seat tube bottle cage mounts and under the cage)

Beamshots:

Set 1:
Control, L2D Turbo, Single P7, Double P7
http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2456.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2455.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2457i.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2458-1.jpg

Set 2:
Control, L2D Turbo, Single P7, Double P7, Double P7 High aim

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2460.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2461.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2462.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2463.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/DSCF2464.jpg

As you can see, in very dark conditions one P7 is almost as good as two. Two pushes the range a little further while giving a better hot spot but overall not needed in dark conditions. Two would help during dawn and dusk though to increase your visibility and help your beam become more visible.

I use this Q5 light from Shiningbeam in addition to my MTE 8 mode P7:
http://www.shiningbeam.com/servlet/the-60/MF-PL1-18650-Cree/Detail

The MTE is bar mounted. The other light is a thrower and is helmet mounted. This gives me significantly improved visibility over just the MTE P7. I rode home through Toronto's pitch dark Don Valley trails yesterday, and had no visibility problems.

As you can see, in very dark conditions one P7 is almost as good as two. Two pushes the range a little further while giving a better hot spot but overall not needed in dark conditions. Two would help during dawn and dusk though to increase your visibility and help your beam become more visible.

Thanks for the shots. They confirm my decision to stick with one P7 for now. During dawn and dusk, I use the 3/sec strobe, as it provides even more passive visibility than the high mode. When I need to affect traffic, I use the rapid strobe, which is even more of an attention-getter.

I use this Q5 light from Shiningbeam in addition to my MTE 8 mode P7:
http://www.shiningbeam.com/servlet/the-60/MF-PL1-18650-Cree/Detail

The MTE is bar mounted. The other light is a thrower and is helmet mounted. This gives me significantly improved visibility over just the MTE P7. I rode home through Toronto's pitch dark Don Valley trails yesterday, and had no visibility problems.

I also ordered a Q5 for a helmet light. the P7 don't spill enough light to the sides to look around corners on the pitch black don valley trail.

I've got my L2D on the helmet, it's nice being able to look around a full 360 degrees while moving forward :)

I've got my L2D on the helmet, it's nice being able to look around a full 360 degrees while moving forward :)

Aha....weren't you in "The Exorcist" ?

Hello,
I just thought I'd show my new light setup which looks to be very good for the amount of money invested. It consists of:
(2) MTE 5-mode P-7s modded to run on external power
(6) 18650 Trustfire 2500mAh protected batteries in parallel
(2) Fenix light mounts superglued on the 90 degree position
(1) Viewpoint spacebar
Also anderson power pole connectors and wiring for the connection.

How do you charge the battery pack ?

How do you charge the battery pack ?

I soldered wires terminated with anderson connectors to my 18650 battery charger, I unplug the battery pack and plug it into the charger.

I soldered wires terminated with anderson connectors to my 18650 battery charger, I unplug the battery pack and plug it into the charger.

Are the batteries soldered together ?

How about a photo of the modified charger ?

Hello,
I just thought I'd show my new light setup which looks to be very good for the amount of money invested. It consists of:
(2) MTE 5-mode P-7s modded to run on external power
(6) 18650 Trustfire 2500mAh protected batteries in parallel
(2) Fenix light mounts superglued on the 90 degree position
(1) Viewpoint spacebar
Also anderson power pole connectors and wiring for the connection.

Beamshots coming soon, I haven't really aimed it properly or anything yet either and the battery pack needs to be dressed up abit.

http://img.photobucket.com/albums/v320/Jam_Master_J/light1.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/light2.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/light3.jpg

http://img.photobucket.com/albums/v320/Jam_Master_J/light4.jpg

Ride Impressions:
I took the bike out for a quick 25km ride that covered many lighting conditions. First the ride started at my home out in the country with potholed roads and very dark. The lights worked great here, I ran both lights on high just to really get the best look at the potholes and cracks in the road. Throw was not a problem at all, I could see very far ahead so 25 km/h was just like during the day. After about 10km I got to a new area lit with streetlights periodically, this was a hard test but with both lights on high I was able to push through that light and still have useable light. Then I pulled into a MUP that is surrounded by trees/bush, wow, this is where a floody light dominates! I could see everything, everything. I pulled it back to just one light and was still seeing everything I could possibly need. And then for a little I got to ride some smooth, straight roads so I went one light high and one medium, this grants the most uniform beam when the high is aimed up more.

Conclusion: Very happy:) The light output is great (I've had cars overtake me and my lights were not being washed out at all), the beam is great with one aimed low and one at medium range and the flexibility of 2 lights lets you find the ideal setup for almost all scenarios.

Let me know what you think.

I am definately a newbie. Is there anyway you could take more pictures of how the battery pack connects to the flashlights along with how you have secured your battery pack along with what it looks like? Your setup is EXACTLY what I am looking for. I appreciate any of your help. Thanks.

My battery pack is nothing special, it's two pieces of aluminum with springs soldered to it and PVC tubing to hold the batteries. It works but I'm about to switch over to this: http://www.candlepowerforums.com/vb/showthread.php?t=213929

Unfortunately I can't really reopen my P7s to take pictures, I may strain and twist the wires too much with all the turns needed. But all you have to do is drill a hole in the side of the body and put two wires in, solder the wires securely to the base of the battery springs (or the ends if you can't reach the base). Make sure it is strong and don't leave any extra, you don't want the positive connection touching the sides of the body, that'd be bad. Use a grommet or some kind of sealant to seal the hole to waterproof it somewhat. With the hole and sealant you've pretty much made this bike light for life unless you want to undo the entire mod and seal the hole.

Now for wiring you've got a ton of options, you're dealing with high currents (in bike terms) here (as high as 6 amps with both lights on high and fully charged batteries). If you're going to use quick disconnects, I recommend to use them near the lights and near the battery pack so both can be detached if need be. You want something low resistance here, I use anderson powerpole connectors.

The main wire can be routed whereever but I just ran it along the bottom of the frame and up below my seat, you want a decent gauge here since it's long and high-ish current. I'd recommend no smaller than 18awg, 16 or 14 is better.

Here's a somewhat dark picture of where the main wire comes off near the back rack to connect a battery:
http://img.photobucket.com/albums/v320/Jam_Master_J/bikebattery.jpg

Now for wiring you've got a ton of options, you're dealing with high currents (in bike terms) here (as high as 6 amps with both lights on high and fully charged batteries)

If those torches aren't direct drive and use a circuit board to drive the LEDs then the current to the LED should hopefully be constant.

If that is the case then the current being taken from the batteries is likely to be at it's lowest when the batteries are fully charged.

As the supply voltage (battery) drops the puck will take more current to maintain a fairly constant power in (W).

The current is likely to be at it's lowest with fully charged batteries and at it's highest just before the batteries are completely drained.

:thumb:

Yep, if the light was really regulated but I'm skeptical of that. But you're right, if current across LED is constant and the voltage of the battery is dropping the current will start low and end high til it drops out of regulation.

If it's got 5 modes it's almost certainly regulated.

How long does it run for ?

Does it dim or stay bright to the bitter end ?

The light just slowly drops down, it seems like direct drive to me. The 5-modes are just created by PWM I think. I don't even know if it's possible to easily make an 18650 P7 light regulated since a fully charged 18650 will push over 2.8 amps briefly and then less as it drops so a simple boost or buck setup wouldn't work.

I don't even know if it's possible to easily make an 18650 P7 light regulated since a fully charged 18650 will push over 2.8 amps briefly and then less as it drops so a simple boost or buck setup wouldn't work.

2.8A is the most a 18650 can supply ?

2.8A is the most a 18650 can supply ?

No it can supply more, but the Vf needed to push over 2.8A is too high for an 18650 except when fully charged.

No it can supply more, but the Vf needed to push over 2.8A is too high for an 18650 except when fully charged.

Wouldn't that only apply to direct drive ?

If you had a 2800 mAh driver it would pull more amps as the voltage decreased ?

Wouldn't that only apply to direct drive ?

If you had a 2800 mAh driver it would pull more amps as the voltage decreased ?

2800mA you mean but yes it should. When I get home I'll measure Vf across the LED as the battery drops down and see if it changes. If Vf holds steady, it is indeed regulated. But I suspect it isn't because when I experimented with some thinner gauge wire, the minor voltage drop across that wire had a visible effect on the brightness of the light which shouldn't happen.