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Topics - Old Guy New Hobby

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Gear Talk / Review: charging batteries with a SON hub
« on: March 15, 2012, 10:59:46 pm »
I use a smart phone, which provides communication, internet access, a camera, and an E-book reader. If used lightly, my phone can stay charged for 2 days. Used moderately, it needs joy juice every day. I have occasionally had problems finding a place to charge the phone when on the road. I decided to see whether a hub and charger could keep my phone well fed. In addition, I use a GPS unit (2 – AA batteries) and 4 flashers (12 – AAA batteries). When riding around home, I use Eneloop rechargables. It would be nice if I could also charge those batteries, at least once in a while. I zeroed in on a SON 28 hub and a BioLogic ReeCharge
http://www.amazon.com/gp/product/B004EBZNSU/ref=oh_o06_s00_i00_details.

Before spending a bunch of money, I looked at whether this could possibly be helpful. Reviews I could find were spotty. I have an electrical engineering background, so I was not surprised when I saw a mishmash of electrical terms. Electrical units are not hard. Power is measured in Watts – electrical watts are exactly the same as the watts we generate when pedaling. To get power, one needs force (V, or Volts) and current flow (current, measured in A or Amps.) The relationship is very simple: W = V x A (Watts = Volts x Amps). To keep my review simple, I will always use Watts. This is a valid thing to do because electronic circuits can trade off volts for amps as needed, keeping the power constant. The circuits act exactly like your bike’s gears, trading force for speed. Of course, these circuits aren’t 100% efficient, but we can talk about watts and get a good idea of how well this should work.

I started by looking at the hub. The performance of the SON 28 hub is available here:
http://www.nabendynamo.de/produkte/pdf/Prospekt_SON_28_Firma_2012.pdf
(Red graph on the first page). As the bike goes faster, the hub generates more power, up to a point. Hub power is limited to 3.5 W. The hub generates 2 W at 6 MPH, 2.5 W at 7.5 MPH; 3 W at 9 MPH; and 3.5 W at 12.5 MPH. If I’m bombing downhill at 30 MPH, I’m not pedaling, I’m having a great time, and my hub is generating 3.5 W.  The power generated is not related to my average speed, but to how slowly I climb. If I stay above 9 MPH, I get essentially all the power. If my speeds drops to 7.5 MPH, I’m still getting 2.5 W. Below that, the power drops quickly. The key point is 7.5 MPH for two reasons. First, 2.5 W is the power drawn by a USB charge (5 V x 0.5 A = 2.5 W). Secondly, the hub starts limiting at 7.5 MPH. Going faster gives a little more power. Going slower gives a lot less.

My first conclusion is the hub generates enough power for a USB charge, but not much more than that. For example, my laptop charger is 65 W. There won’t be any laptop charging going on.

Using the hub to charge a smart phone or batteries requires several electrical conversions. This is what the Biologic ReCharge does. There are other, similar, units. I chose the ReCharge because it is available from Amazon and it has a reasonable price. The plastic blob that attaches to my fork converts the hub’s alternating power to direct power. A circuit inside the battery case charges the battery. A second circuit converts the battery voltage to 5 V and delivers up to 5 W of power to a standard USB connector. The charge status of the battery is indicated by three lights. When I press the center button, a full charge is indicated by all three lights turning on. If no lights turn on, the battery is discharged.

To test charging my Eneloop batteries, I also purchased two Sanyo USB battery chargers
http://www.stefanv.com/electronics/sanyo_usb_charger.html
(use some Velcro strips to strap the batteries in) and a 2-port hub
http://www.amazon.com/Plugable-USB-2-0-Port-Hub/dp/B005HKIDF2/ref=cm_cr_pr_pb_t
AA batteries will charge just about as fast as AAA if I put one battery in each charger. In this charger, one battery charges twice as fast as two.

I am a slow rider, about 12 – 13 MPH average. In hilly areas, I spend plenty of time riding less than 7.5 MPH. In spite of this, everything works reasonably well. I did an out-and-back in a moderately hilly area. I started with a fully charged Biologic battery. Here are my results:

Elapsed Time   Device               Charge         Biologic level
1:45              phone               39% to 93%      3 lights
2:15              2 – AA (1/charger)         charging              2-3 lights
(break for lunch – charger turned off)
4:00              2 – AA               1 done, 1 charging   2 lights
5:00             4 – AAA               2 done, 2 charging   2 lights
6:00             none                       none                 still 2 lights
6:30             none                       none                 3 lights

I don’t know how close to fully discharged my batteries were. I used batteries I would normally throw into the battery charger at my desk. My GPS had issued a “low” warning for the AA batteries. The AAAs were from a front flasher light that ran about 10 hours. The last hour and a half was to let the ReCharge battery recover its charge. It had not recovered after 1 hour, so I rode another half hour to see what would happen. I conclude that if I am not climbing all day, I can easily keep my cell phone charged, and even charge some of my flasher batteries. If you climb faster than I do, you can do a little better.

If you want to try the same thing, here are some tips to keep in mind.

Like many smart phones, when I plug my phone into a computer, it does a “USB” charge (2.5 W). When I plug it into the wall wart charger, it does an “AC” charge (5 W). How does it know? USB devices are supposed to ask the computer how much power they can draw. It’s part of the USB protocol. That’s how the phone knows that 2.5 W are available. How does the phone know when it is plugged into the wall wart? It’s possible the wall wart announces it has 5 W available. Or it’s possible the phone uses some other way to detect the wall wart, either as part of the USB protocol or through some proprietary method. What happens when I plug my phone into the ReCharge? Does the ReCharge have a chip to tell my phone that 2.5 W are available? Or does the phone see no response and assume it should do a USB charge? I don’t know. I have a Samsung Android phone. Biologic includes a USB adaptor they say makes the ReCharge compatible with some Apple products. Some people have reported their Apple device won’t charge from the ReCharge. Did they not use the adaptor? Is the device looking for some Apple-proprietary signal? I don’t know. To mis-quote Abe Lincoln, you can fool some of the smart phones all of the time.

I use a dedicated GPS for two reasons. First, my phone is too expensive to put out on my handle bars. It simply is not made to withstand the punishment it can get out there. My phone goes inside a padded case, inside a zipper compartment, inside my waterproof handlebar bag, with the top firmly latched. Secondly, these little devices draw a lot of power when they are active. It is very likely that some smart phones draw more than 2.5 W when they are used with mapping software and GPS active, and the display on continuously. It’s very possible that some smart phones would lose charge if used as a GPS while receiving a USB charge. (Maybe this is why those Apple products “didn’t charge”.)

When charging batteries, it’s not necessarily important to charge them all the way. When a battery gets to 90% charge, the charger slows the rate of charge to keep the battery from overheating. When using a USB charge, my phone takes the same time for the battery to go from 40% to 90% as it takes the battery to go from 90% to 100%. That’s pretty typical. Of course, if the phone is charging more slowly, the charger is drawing less power, and the ReCharge battery has an opportunity to charge up a little bit.

There’s no way to know precisely what the difference is between 3 lights of charge and 2. It might be that the ReCharge battery loses no charge while charging my cell phone. I have reason to believe that the two battery charges plus USB hub together draw more than 2.5 W. The ReCharge can deliver up to 5 W (until the battery drains). Some hubs “shut down” to avoid damaging the computer if the devices try to draw more than 2.5 W. Just add this to the list of things I don’t know.

I don’t run lights from my hub. I just stick with the flashers. However, the ReCharge can be wired in with lights if you want. If you try to use the ReCharge and the lights at the same time, that meager 3.5 W will be shared between the two devices in some wonderfully wacky way. It might be totally unpredictable. It might depend on the sequence you turn the devices on. Power might rock back and forth between the two. Whatever it does, 3.5 W is not a lot of power to share. If you wire lights with the ReCharge, you should pay particular attention to the SON hub manual. As they state, turning the lights off while riding can create a very large voltage. For many decades, cars ran by having points turn the current off in a coil, which easily generated 1,500 V to fire the spark plug. I’m not saying the SON hub will generate that much voltage when you turn your lights off, but the principle is exactly the same. High voltages can be rough on electronic circuits. So if you wire both of these devices together, you might want to take care to come to a complete stop before turning your lights off.

2
Gear Talk / Folding tires
« on: January 07, 2012, 05:20:57 pm »
I hope to take my first tour this spring. It's nothing special for most of you folks -- Baltimore to Bangor -- but it's a big deal to me. I'm getting new Continental Gatorskins. The bike shop recommends folding tires. I understand the advantage of folding tires for spares, but he's recommending I get all folding tires. He was going through all the advantages of folding tires. When he was done, I was wondering why they make wire bead tires/ Are there any disadvantages to folding tires? I noticed the widest tires come only in wire bead (on at least one site).

3
Connecting ACA Routes / Atlantic Coast Route to Hermon, ME
« on: December 26, 2011, 04:29:58 pm »
I want to ride from Baltimore, MD to Hermon, ME in the late spring. Fortunately for me, the Atlantic Coast Route works great for that. But I don't know the roads in ME. I could take Rte 1A from Stockton Springs to the Hampden area, then pick up Coldbrook Rd to Hermon. Google bike seems to prefer smaller streets starting at Winterport. Or I could shoot up a series of back roads from Belfast. Is one of these better? Is there anything that's important to avoid?

4
Gear Talk / Rain
« on: May 22, 2011, 07:01:37 am »
This is about more than just gear, but gear is part of the question so I decided to post here.

Until this year I avoided riding in the rain. I'll be on some short (2 to 4 day) tours in the coming months. Cold weather won't be a factor, but the dates are fixed; I have to be prepared to rid in the rain. We had a good shower this week (plenty of rain, not too cold, no lightening) and I took a short 45-minute ride. My brakes didn't work very well. After a quick forum search, I installed salmon Kool Stops. My REI Novara rain jacket worked quite well. I didn't feel the need for rain pants, but then again it was a short ride. My plastic shoes were fine, but my cotton socks soaked up the water right down to my toes. Taking care of the bike when I got home was easy, since I had a nice dry garage handy.

I'm finding I can't imagine how I would cope on the road and in a tent if it rains. I could bring a towel to wipe the bike down, but in the morning I would just have a wet towel to go with my wet bike. Wiping the bike down sounds futile if it's raining anyway. I can't imagine how I would lube the chain in the rain. How would my beloved Brooks saddle survive an overnight soaking? Are rain shoe covers useful, or do the feet just get too hot for comfort?

What are your suggestions for riding in the rain?

5
Gear Talk / Handlebar bag
« on: February 07, 2011, 07:05:13 pm »
I'm 62. I've been slowly working up to touring. I'm riding a Trek 520. Last year I was able to ride 65 miles once / week. This year, I plan to do several multi-day rides with some level of support. I will use a tent, but I'll be using restaurants for meals. I have identified most of the items in my touring kit, but I'm struggling with the handle bar bag. I plan to put my wallet, phone, etc in the handle bar bag. I was looking for a waterproof bag that "clips on" for secure mounting and easy removal. So far, the only bags I found are Ortleib and Banjo Brothers.

http://www.amazon.com/Banjo-Brothers-Waterproof-Quick-Release-Handlebar/dp/B003D4EYI4/ref=wl_it_dp_o?ie=UTF8&coliid=I23W4V4XZ474HI&colid=1ML6NQ8HNFZNM

I'm not very happy with either solution. Sometimes I use a map for navigation; sometimes a GPS. (My GPS is a waterproof outdoor unit.) It doesn't seem there will be room to mount both GPS and bag to my handlebars. The Ortleib has both a map pocket and a GPS pocket available, but if purchased with both, it seems quite expensive for what it is. Banjo Brothers doesn't seem to have a way to let me mount the GPS to the bag.

I can't be the first person to want to do this. What am I missing? Any advice?

While I'm at it, are there any books that give great tips about life on the road?

6
Gear Talk / Trek 520 chainring
« on: April 25, 2010, 03:02:22 pm »
I'm just starting out. I rode 2K miles last year on a hybrid and decided I am interested in touring. I bought a new Trek 520 this year and have about 500 miles on it. I'm still working up to my first tour, but I have noticed the gearing is too hard for some of the hills. (At least for me.) The new Treks come with a 11/32 9-speed cassette which I like a lot, and 26/36/48 chain ring. That gets me down to about 22 gear inches. I would like to swap the 26 T for a 22 T, which would get me down to 18 gear inches. But even with the 26 T, the chain starts dragging on the front derailleur 4 gears up from the bottom on the cassette. 

Can the front derailleur be adjusted to work with a 22 T chain ring and give me at least 5 gears on the cassette? Will it work dependably? Or should I settle on a 24 T, which at least gets me to 20 gear inches? Does anybody have experience with this?

I plan to take advice offered in several other posts and include a chain stop to prevent the chain from rolling off the inside of the cassette.

7
Gear Talk / New 520 - setup questions
« on: January 24, 2010, 10:53:52 pm »
I feel like I graduated from being a Nube at bicycling only to find myself a Nube at touring.

Last year was great - I rode 2000 miles on a Schwinn hybrid. I am doing all road riding, but some roads are hardpack + a little gravel. I ride most days. When the weather is bad I ride rollers about half an hour. When the weather is OK or good, I ride about an hour on work days, plus a longer trip on the weekend -- 30 to 50 miles, depending on how much time I have.

I decided I am interested in touring. I will start riding longer as the weather improves and maybe look for a 2-day or 3-day "credit card" trip this summer. After quite a bit of research and reading (including these forums), I decided I will buy a Trek 520. I like the component set, I love the bar-end shifters, and the bike rides well for me.

I have a dealer who will help me with my bike, but like many dealers he's more into road and mountain bikes than touring. I don't need to set up my bike perfectly right now, but there are a couple of things I want to get right from the first. It's OK to spend a little money, so long as I won't have to spend it again later for making a lame-brain decision.

Fenders: I want full fenders that will leave plenty of room for wide tires. Do you-all have a recommendation?

Tires: I currently have 26 x 1.5 inch wide tires with a road tread, and I like them a lot. Plus the Trek feels a little harsh, which I attribute to it's relatively narrow tires. I want puncture resistant tires, but nothing extreme. It looks to me like I should be able to fit 38s on the 520 with fenders. Is this reasonable, or am I looking for trouble every time something brushes up against the fenders? Many folks say good things about Continental Ultra Gatorskin, but they don't come very wide. What would be a good tire?

Lights: I don't ride at night, but I won't ride without flashers front and rear. It's easy to install an inexpensive flasher on the Trek's rear rack, but I can't imagine what a good front light setup might be, considering I may well want to put a front bag on the handlebars later on. I also like to keep the handlebars as clean and clutter-free as possible. I started to look at a couple of sites, but the options seem pretty overwhelming at the moment. Can somebody point me in a good direction?

Saddle: Normally I wouldn't worry about this right away, except that I rode the Trek and found the saddle to be pretty bad. The B17 seems to be the hands-down choice. I was thinking of the Champion Flyer, which I believe is a B17 on a single rail with a spring. Did I get that right? What are the advantages / disadvantages of the B17 -vs- the Champion?

I believe everything else can wait until I get more experience. Thanks in advance for any advice you care to give.

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