Dynamo hubs

am about to pull the trigger on this shimano xt disc dynamo hub.

https://www.rosebikes.co.uk/article/shimano-deore-xt-dh-t785-1d-disc-hub-dynamo/aid:742795

should I be worried in any way that it's 6v and 1.5w??
Most hubs seem to be 6v and 3.0w, wanting to pair it with a B + M IQ Cyo and a B + M Toplight rear brake light, will there be any issues, will the lights be underpowered???

thanks in advance

I read into this a bit as I could have gone for the 1.5w Alfine hub.

Internet wisdom suggested that a 1.5w hub will have a little less resistance than a 3w hub but that in reality the difference was so negligible it would be impossible to detect.

Most of what I read suggested that 1.5w was still more than most modern lights would need so there'd be no difference in brightness but that a 1.5w hub wouldn't be able to run a charger like a Plug etc.

thanks for that, was hoping someone had done the hard research yards. Don't think they'll be using a charger anytime soon, and the price is too good on that hub to pass up..

Online reviews seem to differ between it being the greatest thing in the world to it utter keech with not a lot in between.

Something about this
youtube video makes it look pretty draggy when he spins the wheel at the end.

I didn't think you could use the supernova e3 rear with any light other than a supernova e3 front? The rear uses dc where as most other lights have an ac feed. Worth double checking.

Yeah I saw the video - maybe some of the draggy look might be down to disc rubbing?

I thought it was that you couldn't plug the E3 directly into the Dynamo, you had to run though a front light, any front light would do?

I've asked in the dynamo lights thread so hopefully someone will know.

youtube video makes it look pretty draggy when he spins the wheel at the end.

They all look (and feel when turned by hand) more draggy than you'd think they should, but the reality is that the momentum/kinetic-energy that 80-100kg of you+bike has makes the extra little drag barely noticeable in normal riding.

You'll need to pair it with a 1.5W optimised headlight as you'll never get anywhere near to max light output on the Cyo (1.3W after you take out the 0.2W for the rear). Would be a waste of a decent headlight IMO...

https://www.bike24.com/p2144796.html

D1 just arrived, will report soon how it works with SP PD-8X hub, in parallel with a Supernova Triple + Tail light. Thanks @acharnley!

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Where are you planning to mount it?

Thanks have found the 6v 3w version of it, just a tiny bit heavier and a bit bigger so will be grabbing that one instead...

Definitely a better bet if you want to charge things in future too.

The E3 works together with other frontlights, but misses the standlight if not paired with a supernova front. Better choice would be http://www.bumm.de/produkte/dynamo-ruecklicht/toplight-line-small.html

Hmm, not much use without the standlight.

I've contacted Rose's UK guy to try and swap that B&M Toplight for the E3 but he said his German colleagues were so efficient that my order may already have been dispatched (this was when I called him yesterday, 2 hours after placing the order!) but he doesn't seem to share their work ethic as he hasn't gotten back to me to let me know yet.

Best part is, the B&M is about 30 eur cheaper. There's a SON tail light that looks just like an alloy version of the B&M but it's even dearer than the Supernova.

Actually no, the best part is the URL for the B&M website, bumm.de Megalolz.

The USB cable has detached from the on/off switch on my Luxos IQ2. Can anyone recommend a fixer?

Should be too hard a job to disassemble, strip the wire and solder?

The SON rearlight is just the B&M with a different caseing.

The alloy casing is nice but not worth the 30eur + difference.

I haven't found any suitable place yet :(, so it will be inside the framebag meanwhile... Maybe with a very long stem faceplate screw I could attach it to the other end...

A device that accepts 3W of charge power will take twice as long to charge. If the 1.5W is less than its power consumption it will indicate it is charging but will discharge (more slowly). 3W is on the threshold for many devices (smartphones especially). Personally I wouldn't buy a 1.5W dynamo.

The 3W XT version isn't much more, it's what I use (over here in the UK it's called the 3N80). There's also the cheaper 3n72 (LX) version if you can stomach the 100g weight penalty. The internal electrics are identical. These are the only Shimano hubs worth considering in terms of resistance -v- efficiency.

As I recall the 3n72 was painted black and became an Alpine. Can't remember the model number however.

Thanks for that, have found the 6v 3w version on rose bikes, think I had a bit of a brainfart when putting stuff into my basket.
It's not for me but for the girlfriends commuter, but I'll probably be in the market for another disc Dynamo hub when I buy/build up the titanium super commuter in the next year or so. So it's all good info to have stashed away..

The Alfine versions are DH-S501 (3W, a DH-3D72 in disguise) and the DH-S701 (1.5W a DH-1D70). Dont bother unless you want matchy Alfine logos, get the DH-3D80/DH-T785 instead.
The DH-3D80 and DH-T785 are both sold in the UK, polished silver and anodised black respectively, and are identical other than finish.

Dynamo noob question, will wheeling my bike backwards out of the garage fry anything within my Dynamo hub/lights?

No.

http://bikepackersmagazine.com/k-lite-review/?utm_content=buffer09f9e&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer