2AA Fenix as backup to a generator hub?

[Super Dave]

Aloha,

I'm stoked, my wait is almost up for a Curt Goodrich frame.

I plan to have a SON generator hub with the IQ Cyo headlight.

Does it make sense to have a 2AA fenix mounted on the front rack as a back up? If so, what current Fenix would be the best bet?

What kind of clamp is made for these lights that can be bolted to the rack? Trying to save Curt some time...

Thanks a lot,
DF

 

[AlexLED]

Hi Dave, sounds like a plan !

I use the TwoFish blocks:
http://www.britelumens.com/TWOFISH.html

They should work perfectly with most AA lights.

Current Fenix models are LD10 and LD20, but both only use a X-RE Q5 LED.
The current 4sevens models, for example, are a bit brighter because of the XP-G R5 LED:
http://www.4sevens.com/index.php?cPath=297_305

 

[BentHeadTX]

Fenix will be updating their L20 series to XP-G LEDs the 5th of March

I have two XP-G lights, a 4sevens Turbo AA2 and a EagleTac P20A2 (both run on two AA cells) Of the two, I would recommend the EagleTac because it has a wider beam and 10% more lumens while having a 20% longer run time. It closely resembles the beam of a Fenix L2D Q5 that I previously used.

For AA use only, get the EagleTac for longer runtimes. If you plan on running lithium-ion, then take your pick.

For the record, I use a EagleTac P20A2 for my bike mounted light and a 4sevens Turbo AA1 (switched it to a single AA body since it has good throw in a narrower beam) the AA1 is used as a helmet light. Love the "AA1" Turbo but it will cost you some bucks since you have to order a $20 body with the $75 light.

The new Fenix lights should be debuting on Friday, should be interesting to see what they have this year.

 

[Super Dave]

Thank you both for the suggestions.
Aloha,
DF

 

[yellow]

You wont use the stock hub light any more, as it will be blown away from the Fenix with ease (and the Fenix does not even need XP-G led for that).

Even a good light for a hub - thats one that is homebuilt and features at least three led - has about no chance against a single die led driven with full power.

 

[znomit]

You wont use the stock hub light any more, as it will be blown away from the Fenix with ease (and the Fenix does not even need XP-G led for that).

Even a good light for a hub - thats one that is homebuilt and features at least three led - has about no chance against a single die led driven with full power.

Hubs drive LEDs at 500mA. A three led setup will be about 2x brighter than a fenix. Commercial dyno lights will have a significantly better beam pattern than the fenix which adds to the efficiency too and some of them put out 680lm, and they don't need XP-G for that.


I just run a blinky as a backup most of the time on the roadie. I have found the dyno lights to be very reliable. If its an epic ride I take a bright helmet light. Always run the helmet light on the MTB too.

 

[yellow]

is a light - like the Supernova - REALLY an option?
aside from overpriced, it is just overpriced

PS: my town bike has a three led setup for years now, atm XP-E R2 and homebuilt of course.
The dyno makes about 600 mA
... so very comparable to all those very new and overly priced "super"hublights.
--> whatever the current speed is, when my main MTB light (an XR-E P4 modded 6P) is powered on with its ~850 mA, the triple light is hopelessly far away.
Of course thats just personal impression, no technical measurement.

 

[markus_i]

Hubs drive LEDs at 500mA. A three led setup will be about 2x brighter than a fenix. Commercial dyno lights will have a significantly better beam pattern than the fenix which adds to the efficiency too ....

- Hubs generate ~500 mA. The LEDs in the b&m and Schmid lights are driven with a little less than the double of what the hub delivers, since they contain a driver circuit.

- Overall efficiencies vary highly, I wouldn't go as far as estimating a mere factor of two just from theory - and that factor of two is basically the minimum you need in order to notice anything.

- I'd definitely support your statement regarding the beam pattern, though. Given otherwise the same conditions, a light with a beam pattern designed for road use will put at least 2x the light on the road compared to a regular flashlight (ok, see above about that factor of 2 ;-) )

As to the original question - you might consider either carrying the light in your pack as backup (where the batteries will have died by the time you need it...) or keep it on the handlebars for these pesky slow uphill sections or simply to errrmm... notify oncoming motorists that you are blinded and would be obliged if they might be bothered to dip their headlights....

Bye
Markus

 

[Super Dave]

Thanks for the replies.

I heard that the SON 20 and SON 20R generator hubs have no problem powering the IQ Cyo (LED) even at very low speeds going up hills.

Thanks,
Dave