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-   -   Brompton bottle vs hub dynamo? (http://www.bikeforums.net/folding-bikes/851082-brompton-bottle-vs-hub-dynamo.html)

trrubicon06 10-07-12 08:10 PM

Brompton bottle vs hub dynamo?
 
I've been looking at some sort of dynamo system for my brompton. My goal is to basically use it to charge my phone or a gps, but would probably add lighting eventually. I've read a good deal on both systems, but get equal pros from each. I can get the shimano dynamo wheel for $160 and a bottle dynamo by Axa for $39...then the expense of the charger/lighting.

What I like about the bottle dynamo is that I can completely disengage it when not in use. The previous brompton dynamo was a Axa bottle dynamo and people had nothing but problems. But, I'm wondering if its bromptons choice of attaching it to the bike, smaller wheels, or user error.

Anybody have experience with either?

LWaB 10-07-12 09:17 PM

Bottle dynamos never last long on a Brompton. Vibration and corrosion of bearings are a powerful combination. Many bottle dynamos will flick themselves onto the tyre when going over a bump (the catch often isn't good enough), due to being mounted on a small suspended wheel.

jur 10-07-12 09:23 PM

I bought a wheel with SP hub dynamo and light - these are getting rave reviews and are much lower than the expensive Schmidt. Plus they work better. Here's a fb page:
http://www.facebook.com/SpDynamoSystem
I found a vendor on ebay who sells complete Brompton wheels. For reasons I don't remember we concluded the transaction off ebay, probably because I wanted something different to what was offered.

[edit] here's a link but my vendor was someone else:
http://www.ebay.com.au/itm/SP-hub-dy...ht_1624wt_1163

trrubicon06 10-07-12 09:54 PM

Quote:

Originally Posted by LWaB (Post 14817162)
Bottle dynamos never last long on a Brompton. Vibration and corrosion of bearings are a powerful combination. Many bottle dynamos will flick themselves onto the tyre when going over a bump (the catch often isn't good enough), due to being mounted on a small suspended wheel.

That's what I'm afraid of with the smaller wheels.

fietsbob 10-07-12 11:01 PM

You can buy a hub from Brompton sources 28 hole ,
or a Caprio hub like bike friday offers in 24 hole .

happen to have had a Mk2 Brompton 3T
its bottle dynamo hydroplaned when rolling on a wet tire
and so was useless on the Oregon Coast 3/4 of the year
so I adopted a Battery light.

http://www.cyclofiend.com/working/20...clark1110.html

there is also a Schmidt hub dynamo in both drillings and
an 8 and 9mm axle.. Brompton Spec 28 hole 8mm dropout.74mm wide..

once Shimano had a cheap enough Hub dynamo..
the bottle dynamo Option was dumped.. by the Mfg.

for zero drag bring the USB cable and charge your stuff when you get there.

badmother 10-08-12 12:26 AM

http://globalcyclesolutions.files.wo.../p10009411.jpg

http://gcstz.com/products


Scroll down to item 3.

Not sure about putting anything electric that close to the ground on a Brompton (apart from a hub dynamo).

fietsbob 10-08-12 11:36 AM

B&M bottle dynamo has an optional wire brush like wheel,
that will dig into the tire better in wet weather, But ,
I expect it will be hard on the strip around the tire it contacts.

so setting it up to roll on the thick tread rubber will be better
than the thinner on the sidewall..

trrubicon06 10-08-12 12:33 PM

Quote:

Originally Posted by fietsbob (Post 14818829)
B&M bottle dynamo has an optional wire brush like wheel,
that will dig into the tire better in wet weather, But ,
I expect it will be hard on the strip around the tire it contacts.

so setting it up to roll on the thick tread rubber will be better
than the thinner on the sidewall..

I have Marathons on my brompton and they have the dynamo strip on the sidewall. I'm probably gonna go with the Shimano hub, even though its a bit more then the bottle. Everything would be contained and have little worries...hopefully it lasts though.

Non folding/brompton question... Anyone have experience with the USB chargers from bike2power.com? They basically plug into the dynamo and then provide a switch for lighting or USB.

trrubicon06 10-20-12 09:16 AM

Thought I'd add an update of my Brompton dynamo upgrade.

Shimano dynamo with Biologic Reecharge dynamo kit attached to the fork. Don't mind the light...hadn't received my dynamo light yet.
http://farm9.staticflickr.com/8188/8...08e9dc12_z.jpg

I ran the Reecharge wiring along the front brake cable.
http://farm9.staticflickr.com/8327/8...d010d315_z.jpg

http://farm9.staticflickr.com/8325/8...814b079e_z.jpg

http://farm9.staticflickr.com/8468/8...d9cedd5e_z.jpg

I wrapped the wiring around the handlepost until I figure out my phone/gps mounting. Then I will cut to length. The Reecharge wire end is universal male end and comes with a micro-usb adapter.
http://farm9.staticflickr.com/8469/8...4429b3aa_z.jpg

Avenir 3w led dynamo light. Decent light for $27.
http://farm9.staticflickr.com/8323/8...f20b934d_z.jpg

http://farm9.staticflickr.com/8470/8...410c4dcc_z.jpg

I did heat up the mount and bent it to clear the lower headset cup and over the brake. Could probably use the Bromptons factory light mount as well.
http://farm9.staticflickr.com/8331/8...930a9491_z.jpg

GlowBoy 10-21-12 11:15 PM

When there's no electrical load, modern dynohubs cause very little drag. Something like 2-3W IIRC; if you're concerned about that amount of drag, you're not going to be riding on small wheels in the first place. I converted my Swift to a dynohub this summer, and have absolutely no regrets about it.

My understanding is dynohubs are quite a lot more efficient than bottle dynamos, even their newer, more modern iterations.

trrubicon06 10-22-12 06:15 AM

Quote:

Originally Posted by GlowBoy (Post 14866160)
When there's no electrical load, modern dynohubs cause very little drag. Something like 2-3W IIRC; if you're concerned about that amount of drag, you're not going to be riding on small wheels in the first place. I converted my Swift to a dynohub this summer, and have absolutely no regrets about it.

My understanding is dynohubs are quite a lot more efficient than bottle dynamos, even their newer, more modern iterations.

I chose the hub route as my post above shows.

GlowBoy 10-22-12 10:46 PM

I know. Just chiming in with another confirmation that you made the right decision.

elzy0000 10-23-12 12:25 AM

Quote:

Originally Posted by trrubicon06 (Post 14861340)

I like the luggage release thing you have rigged up there.

rifraf 12-21-12 08:31 AM

I believe you made a much better choice going with the hub dynamo. Its fitted so now you can basically forget about it. I went with a similar setup in that I used a Sondelux dynamo hub and an Edelux headlight.
To utilise the dynamos power to charge my gps I went with a B&M E-werk with cache battery which will also charge my phone. I'm very happy with my set up and have no regrets about the initial setup cost. Anyone whose had to sit in a caravan park laundry or bathroom for hours to charge some batteries knows what a pain this is whilst on tour. Glad I spent the money as I now have to give no thought at all to lighting nor gps/phone charging. The convenience is well worth the expense.


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