Jan
22
2010
I have been successfully using the jawetec bikecharger in combination with several devices for several trips at my bicycle, and I really like it. Today I received the information Jawetec’s web page is no longer available. Currently I have no clue whether their bike charger is still available somewhere. Since this great little gadget has been mentioned many times within this blog, please be aware that any links to the Jawetec page from this blog have become obsolete. I do not know, what happened to the company. In my opinion the Jawetec charger is one of the most useful accessories with bicycles and dynohubs, and I very much regret if production is stopped. There are similar products out there, but those are more expensive than the lightweighted, sophisticated, reliable and small Jawetec bike charger.
By the way, in spite of the fact that this blog has not seen updates for quite a long time, the Big Dummy is in happy use. 2009 milage compares to 2008′s. Snafu Knob Job tires, however, show far better durability than the Fat Franks used before. Apart from that, the Token bottom bracket again shows up some outer slackness, so I will probably use ordinary Shimano square tapered or whatever in the future.
Dec
06
2008

GPS device installed to 31.8mm bicycle handlebar by use of bicycle holder and rubber tubing

GPS device installed to motor scooter by use of bicycle holder and rubber tubing
Bicycle Holder Installation
Within the last weeks I have been gathering some practice with my new Garmin GPS, an Oregon 400t model. It was attached to my MTB, the Big Dummy, a motorcycle and a scooter. Finally I installed two bicycle holders, one at the Big Dummy and one at the scooter. I will need to buy at least two more of them. The Garmin bicycle holder for Oregon and Colorado models is simple and cheap, but it is not ready for hard bumps and impacts, probably dropping the device incidentially. Thus I had to feed in some layers of soft rubber tubing to prevent heavy shattering of device. While this was possible in an easy and efficient way at the scooter due to its thin handle bar stay providing space for a thick rubber layer, at the Big Dummy I had to keep my anti vibration layer quite thin due to thick 31.8mm handlebar. See images to compare both mounts. Nevertheless, I am hoping there is enough rubber to make it absorb hard shaking and keep device in place.
There are several GPS mounting systems available as like Bikertech customized, Ram Mounts, Touratech and probably lots more, most of them fairly well addressing the oscillation issue, but in my opinion they are way too big and heavy for my small vehicles, also quite expensive.
Power Source
Lengthy trips require some thoughts about GPS power supply. Batteries may be sufficient for one or at most two days of continuous use. Some battery charger will be needed most likely, since the Garmin would never recharge its batteries inside when plugged to some USB power supply.
Trying to avoid another battery charger in my baggage, I connected the Garmin to my hub dynamo via the JaweTec Bikecharger mentioned previously here. Basically this works, but it is far from being a perfect solution:
- With the SON 28 dynamo a continuous speed of at least 10km/h is required to provide enough power for the device. As soon as riding slower the GPS will start beeping and switch to battery if possible or just shut down.
- The charger is not recognized as a simple power supply. By default the GPS goes to mass storage mode when the charger is switched on. To prevent this, the devices USB interface needs to be set to Garmin Spanner mode, which means, for every short power outage one needs to confirm switching to GPS mode instead of mass storage mode at some popup window coming up with a nasty beep, again and again. Thats sort of cumbersome.
For the motorcycles there is no problem about power supply since it can simply be wired and plugged to the battery via some modified USB converter taken from my previous navigation device. Thus I can run it without any battery inside which is strongly recommended with offroad usage. For the Big Dummy I am still in search for a better solution. I may probably connect a special battery charger to the JaweTec charger and keep a pair of fresh batteries there, but actually I do not really like this, since it requires taking along too many small devices and batteries. I may probably just get a small and lightweighted charger and recharge batteries every night, leaving the JaweTec charger at home.
Another feasible solution would be the dynohub driven Zzing USB charger providing internal battery buffering (unlike the JaWeTec charger) for devices not being capable of USB charging. This way the Oregon GPS could be used totally without its batteries (keeping it lightweighted with better protection against bumps and vibration). However, the Zzing charger is quite big.
As to some readers comment the Australian company Pedalpower+ provides DC hub generators and several more interesting mobile power supplies for bicycle usage.
I finally decided to stick with my reliable JaWeTec charger and put some USB chargeable power buffer, called PowerTank by SwissBatteries in between the charger and the Garmin Oregon. I will give it a try and report about it.
Tags: 400t, batteries, battery, bike charger, buffering, Garmin, GPS, gps holder, handlebar, navigation, Oregon, power supply, powertank, routing, rubber, swissbatteries, tubing, unbuffered, usb, zzing
Filed in Bicycle Electrics, Technical | flatboarder | Comments (0)