# Nitefighter BT21 or Nitefighter BT40s (first light)



## zerafael (Nov 25, 2015)

Hi there.

I am searching for my first light to be used on the bars.

It will be used mainly on Trail.

I only want a light to be used on the bars.

Witch one is better for the bars? BT21 or BT40s.

I have heard that the BT40s is better for the bars but it disperses the light a lot. Since i am only using one light is it better than the BT21?

There is a better light around the same price?

(Sorry for the bad English)


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## ledoman (Apr 17, 2012)

First of all, DON'T USE JUST ONE LIGHT (EVER). Specialy if it is Chinese light. This is safety rule #1. But it's your life.....

Use both you mention and you can't miss. Of course it's up to you. If you must I would use BT21 for the bar. Again, it depends on speed. If you are slow, then BT40 would be better.


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## zerafael (Nov 25, 2015)

Since it is my first light i want to buy a kit with a decent battery pack. That is the reason for choosing nitefighter. So for now i am thinking buying the BT21 for the bars and in the future might buy the BT40 and then switch them.

Thank you for the response.


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## garrybunk (Feb 12, 2014)

Well according to info in the BT21 thread, the BT21 is no longer available for purchase, so there's your decision - go with the BT40S. The BT40s's beam isn't THAT widely dispersed. I (& Cat) call it "wide throw".

Here's a beamshot "stock" (unmodded). +/- 185 feet to the trees:


Here it is an a "wooded trail" setting:


I think the BT21 would have been a bit too narrow of a beam in stock form for the bars (but changeable with different optics).

-Garry


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## tigris99 (Aug 26, 2012)

If your riding trails, going out with one light is dangerous unless with a group. If you crash or anything that causes damage and light doesn't work anymore, you have no light to get out with. At the very least bring a decent edc flashlight with you so you have a back up light . Its ok if your with a group, but going by yourself is just begging to get hurt or killed if you out on trails somewhere and no back up light.


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## zerafael (Nov 25, 2015)

From the pictures is decided. Going to buy the BT40s full Kit. Thanks


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## tigris99 (Aug 26, 2012)

Here's both being used on trail:


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## rsilvers (Aug 23, 2015)

tigris99 said:


> If your riding trails, going out with one light is dangerous unless with a group. If you crash or anything that causes damage and light doesn't work anymore, you have no light to get out with. At the very least bring a decent edc flashlight with you so you have a back up light . Its ok if your with a group, but going by yourself is just begging to get hurt or killed if you out on trails somewhere and no back up light.


While I would always ride trails with two lights, I could get back with my iPhone LED if I had to. I assume we all carry phones that have a bright LED.

I just rode two hours on a trail with three others, and one guy's cheap-ass Chinese light battery died after 1.5 hours. I lent him my backup CygoLite 550, which was still going strong on max power when we ended after two hours.


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## tigris99 (Aug 26, 2012)

Ya too many ppl dont get the fact that being cheap and buying eBay lights with batteries, the batteries arent going to do very well. Good thing u had a back up lol.


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## rsilvers (Aug 23, 2015)

Well to be fair to the light, it may have only advertised 90 minutes of light.

I do a lot of two-hour bike rides, so I am really not interested in any light that won't do 2.5 hours on the highest power when new. That may mean that I need 6x18650, which is what I would be buying anyway except that they make you buy a BT21 with 4x18650.


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## Big Fil (Nov 5, 2014)

Not sure why people want to ride with the highest setting for the entire ride. Use the lower modes for climbing (you don't need much) and kick up to the higher modes for the descents where your going fast. Usually that is only a fraction of the time riding. There's certain times of the month around the full moon that we don't even use lights on the climbs


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## rsilvers (Aug 23, 2015)

My ride was non-stop endless tight 180 degree and S-turns over rocks and roots and up and down hills. I had about 2000 lumens and it was tolerable, but 6000 would have been better.

https://www.strava.com/activities/439461643

But often 400 is fine.


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## zerafael (Nov 25, 2015)

I bought the Bt40s kit from gearbest. It was shipped today. Next year it will be here lol.

For the helmet is the Convoy S2 Cree XM-L U2 a good fit with Bt40s tint?


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## garrybunk (Feb 12, 2014)

Depends on the tint of the S2. BT40S is a 4C tint per my analysis but a 3C should blend ok too. However, a Convoy M1 is better suited for the helmet. An S2 will be very floody with little throw. The M1 will throw better and also handle heat better. See the link in my signature for my own M1 helmet light builds. 

-Garry


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## 8iking VIIking (Dec 20, 2012)

How would the BT40s on the bars pair with a Niterider Lumina 750 on the helmet? Are the tints similar?

Sent from my SCH-S968C using Tapatalk


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## garrybunk (Feb 12, 2014)

Guessing Niterider Lumina 750 is cool white so you'll have a clash of tints. People will have different opinions, but most seem to very much dislike the mix of tints. Me, I've never mixed tints so I can't say.

-Garry


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## 8iking VIIking (Dec 20, 2012)

garrybunk said:


> Guessing Niterider Lumina 750 is cool white so you'll have a clash of tints. People will have different opinions, but most seem to very much dislike the mix of tints. Me, I've never mixed tints so I can't say.
> 
> -Garry


Yeah I guess I'll just have to try it out to see how I like it. I've been just running the lumina on my helmet but I've got a bt40 on the way.

What exactly is the downside to the mixing of tints? Just the distraction factor?

Sent from my SCH-S968C using Tapatalk


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## andychrist (Aug 25, 2011)

8iking VIIking said:


> What exactly is the downside to the mixing of tints? Just the distraction factor?


That among other things. Our brains have their own automatic white balance, which is why we don't perceive the same blue tint that an unadjusted camera would pick up on a clear day. So even if your single bike lamp puts out either a very cool or very warm light, your eyes will adjust. But, with two lamps of unmatched color temperatures, you coud see a marked difference between them, even if they are close in bin. Here's an indoor test of a 4C and 3C ; they are both considered Neutral White but you'll notice an obvious difference in tint.









Funny though but I run both these lamps on my commtbr bike and it doesn't bother me. Have them set up with the 4C (Yinding) as low beam and the 3C (KD 880 clone) as high, with just enough overlap that the two lights combine to form one long beam. Color changes so gradually within its length, all I can tell is that it is warmer looking in front of my wheel than at the horizon. Actually enjoy this setup, but because the Yinding is fixed to the bike frame and the KD to the bars, when the bike is making a turn the two beams separate and I become more aware of the slight color variance. Not a big deal because the lights are spread out over the terrain, as opposed to the concentrated spots in the test example which were projected onto a solid white background. But if the high beam were really cool then I think the difference would get annoying real quick.​


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## ledoman (Apr 17, 2012)

Andy, on the picture very likely 4C is on the left and 3C on the right, isn't it?


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## tigris99 (Aug 26, 2012)

4c seems almost d range tint lol. Which I have seen and read of the tints varying slightly outside of what you'd expect. So a 3c looking more like a 3d tint and so on. My fenix with 4c is much more yellow, dont get that pink tone.


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## andychrist (Aug 25, 2011)

ledoman said:


> Andy, on the picture very likely 4C is on the left and 3C on the right, isn't it?


Yes, thanks for the correction ledoman. I shouldn't post past my bed time!


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## ledoman (Apr 17, 2012)

No problem. Probably you have had set your camera to Auto white balance since 3C appears cool white on the picture. In reality they should look bit different.


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## andychrist (Aug 25, 2011)

tigris99 said:


> 4c seems almost d range tint lol. Which I have seen and read of the tints varying slightly outside of what you'd expect. So a 3c looking more like a 3d tint and so on. My fenix with 4c is much more yellow, dont get that pink tone.


Well as ledoman noted, I had my 3C and 4C inverted, D'oh! My Yinding 4C also looks more yellow to me, or at least platinum, when viewed alone. But pairing it with a genuine 3C and it will appear more pink/sepia and the 4C kinda blue grey. IIRC you had the same experience once too?

So point remains the same, even two slighty different [white] bins can look very different side by side. Though if you were to look at either individually, each would just appear white. Because the brain's white balance can only deal with one overall hue at a time. Like when you're riding on a highway at night, and a line of oncoming vehicles pass by. Some will have HID headlights, others halogen. Seeing them all together and the HIDs will look ice blue and the halogens almost a burnt ochre I think its called.


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## andychrist (Aug 25, 2011)

ledoman said:


> No problem. Probably you have had set your camera to Auto white balance since 3C appears cool white on the picture. In reality they should look bit different.


Huh, somehow my previous reply must have got deleted. 

Yeah my iPad automatically adjusts, only way to control white balance would be to shoot or edit through a third party app. But the picture above is still pretty close to how I saw the two spots, as my brain cannot adjust white balance for two separate hues either.


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## garrybunk (Feb 12, 2014)

The original Yindings were closer to a 5B1 tint, so even more yellow/orange than a 4C. See my tint analysis on the Yinding here.

-Garry


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## andychrist (Aug 25, 2011)

Agree the [first GearBest] Yinding leans yellow/orange, but one I have is still definitely not as warm looking as the 5B1 appears in the 808 clone I soldered it into. Might be more an issue of single emitter reflector versus dual optics though. Phosphor on 5B1 from FastTech maybe a slightly deeper tone than on Yinding. Either make 3C look cool by comparison.


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