Saturday, October 25, 2008

Video of the 'Week': The Cat Came Back

The Cat Came Back was a minstrel song first penned by Harry S. Miller in 1893. It has been played and rerrecorded n various forms in the century + since it was originally published. This gem I found on YouTube is a modern take on this old classic:



Enjoy!

Thursday, October 23, 2008

My review of the Giant Twist Freedom DX




For the past 8 years I have regularly commuted to work via bicycle. When possible I'll also leave the car in the garage and use my bike to run short errands. Of course living in an area with hilly terrain means lots of huffing and puffing, lots of gear shifts, and a decent amount of sweat. The side benefit is I get some much needed and regular exercise. (We'll discount the occasional trip to the ER from dramatic wipeouts at speed.)

Weather is the biggest limiting factor. Too hot and too cold and the bike stays home. Same for rain and snow. Hot days are the worst since I can't afford to arrive at the office all hot and sweaty and stinky. For some reason my coworkers aren't too happy about it. There also are days when the day seemed to last too long and my legs are lead weights on the ride home. Throw in a headwind (why is it always a headwind and never a tailwind?) and the ride can be miserable.

For this reason I was looking for a second bike to throw into the arsenal, one of those new-fangled electric hybrid bikes that require pedal effort to engage the electric motor. Giant Bicycles built several such models but they always were discontinued after what seemed like a short production run. Their latest entry into the hybrid electric market is the Twist Freedom DX.

The Twist DX features twin Li-ion batteries, a 250 watt front hub motor, 7 speed hub shifter, and a claimed range of up to 75 miles with a rider of perfect BMI, flat roads, temps in the range 60-75F, and no wind. I wanted to know how such a beast would behave in the more 'real' world: semi-hilly terrain, a rider and backpack combined weight close to 215 pounds, fall temperatures, and throw in a nasty headwind every now and then.

Unfortunately it seems the only on-line review I could find was from May 2008 by Popular Mechanics. Unfortunately a late spring ride in flat Central Park in New York City did not satisfy my criteria for a good review. Not to knok the fine folks at PM, but they just did not test it in 'my' conditions.

So one day I received a phone call from Erik at The Bicycle Shop. Erik knew I was interested in the Twist so he was kind enough to loan it to me for a few days. I just hope he hasn't sold my regular bike waiting for the hybrid to come back home!

I rode the bike for a few days to drain one of the batteries down, fully charge it, and run it again until the battery drained so I could get an estimate of range and power required to charge it back up. I also wanted to see if it was as 'un-bike like' as the PM review made the experience out to be.

So let's start with the good:

Power is great! At any time you can be in any 4 of the 7 speeds of the hub shifter. I could accelerate strongly even in high gear, trading range as the motor had to work harder. On my commute home a hill that normally takes me 11 minutes to climb blew by in only 7. I was not pedaling as hard as on my regular non-electric bike but I was still getting a good workout although not as vigorous. You still have to supply some of the motive power. One evening there was a stiff headwind. Not only did I still make good time I arrived at home not feeling all beat up by the wind.

Now for the not so good:

Hill climbing power is good but definitely gave up a few mph. It is certainly not insufficient power and was an acceptable tradeoff. Hoever, pull a lot of hills in the Twist DX's Sport mode and watch the battery drains FAST. Use 'Normal' mode and they still drain pretty quick although not at as rapid a rate. The geek in me wishes there were an ammeter to monitor how much power was going to the motor.

As a commuter I have a backpack with a heavy laptop computer and lots of paperwork. Being slightly overweight myself the Twist DX had a lot of stuff to pull up that hill. I could see right away we were not going to get anywhere near the 75 mile range ('Eco' mode in flat terrain), which of course I did not realistically expect, but I was hoping to get closer to the rated specs for 'moderate hill'. I doubt I could climb PA26 from Pine Grove Mills to Joe Hayes Vista on a single charge (it is one heck of a climb).

I expect the range to get slightly better as the battery packs get conditioned by having a few charge cycles on them but currently have no way to scientifically validate that. I should also point out that temperatures were in the range 40-50 degrees F during my rides and the cold does affect that state of charge somewhat. Overall my range was more in the range of the 'steep hill' part of the range chart Giant supplies rather than 'moderate hill'. A re-review after a change to a warmer season and a few charge cycles on the packs should verify the above hypothesis. At the very least with current observations we have a measured range performed under less than ideal conditions and much closer to real world (or at least real world Happy Valley).

And now, the rest of the story:

I drained one of the two battery packs in appx. 18 miles. In those 18 miles there were some good hills to climb. The Twist DX and I blew past riders struggling in low gear, who watched in amazement as we went by at what seemed like light speed. Miles were mostly accumulated in the DX's 'Normal' power setting although a few hill climbs were conducted in the 'Sport' setting to see how fast I could get up the hill.

At the end of each of my 3 mile legs I always felt like I wanted to ride more. Even after a long day in the office with leaden legs the Twist DX made the ride a pleasure. Even at the end of the battery's charge the motor still pulled strong, losing power in probably the last minute or so of the charge cycle. I don't know if Giant fully depletes the battery or simply cuts it off at some lower level.

Range anxiety is mitigated by having the second power pack to switch to when the first depletes. When the 'Right' battery went down to 0 and cut off, I simply flipped the selector to 'Left' and was happily using the power assist once again.

With he battery depleted I hook the charger up to a power monitor to see how much electricity it would require to fully charge. The charger drew a measured 62 watts and consumed .26 kWh to charge the pack. At $.09/kWh, this translate to a smidge over $.02 electricity for 18 miles or an astounding $0.0013 / mile. It costs more than that just to start mt car!

Random thoughts:

Clearly set up as a single model for both the US and European markets, the charger comes with a European power plug and a dongle to convert said plug to a standard 3 prong one. I don't mind but dongles can be easily lost if not careful.

The Twist DX comes with an LED tailight that runs off its own batteries. Curiously, no headlight.

I have a habit of resting my foot on the pedals while waiting at stoplights. This habit would activate the torque sensor and make the front wheel want to spin. Off the line acceleration is strong so if you're not careful you can fly out into traffic. I almost did! I'm surprised Giant didn't put in brake cutoff switches.

The integrated pannier system hides the batteries and also provide some storage space. They were too small for my laptop computer and might even be too small for a MacBook Air. They were large enough to hold my paperwork folders but since they won't hold the laptop I'm still going to need the backpack. They were large enough to hold my lunch.

Giant does not recommend using a child carrier. My own children are too big for a carrier but I was hoping to use one to haul a week's worth of groceries from Wegman's. One can only fit so much into a backpack!

Top assisted speed is 15 mph. Anything above that you have to pedal to get there.

The power connector for the front hub motor makes for a somewhat wider than normal front wheel profile, making it interesting to park the bike in some bike racks. I had no problems with the rack in front of Wegman's.

Giant states in the owners book to specifically not leave the bike out in the rain.

The bottom line:

I was hoping for range closer to the advertised 75 miles but I suspected this would be too optimistic given the weight I expect it to carry and given the terrain. I find it to be an excellent commuter vehicle, provided you want to live life in the bicycle lane instead of the fast lane. The Twist DX will appeal to those who's litany of reasons not to ride a bike are effort to overcome local terrain and aversion to arriving at work sweaty and tired.

Its $2,200 list price leaves you wondering if you would buy a used commuter car or cheap scooter instead but I'll challenge there's nothing like riding a bike on a quiet uncongested bike path. As the PM review suggests, serious bikers will likely shun this bike, but they're not its intended market. The Twist DX will appeal to commuters and errand runners like myself and it offers a no excuse option for those sitting on the fence saying they'd love to bike to work, but...

I really hope that its asking price of 2 large doesn't relegate it to niche status. Go try one for yourself. You'll enjoy the experience.

The bottom line:

Would I buy one for myself? That is a tough question! Obviously I hated to part with the Twist Freedom DX at the end of the review period. I wuld love to have this bike as part of my fleet. At 2 large it is a tough decision to make. But yes, I am saving my pennies.

Acknowlegements:

I wish to express my gratitude to Erik and the Bicycle Shop for the extended test drive. Not every bicycle shop would loan out such an expensive machine for an open-ended test period, especially with the only collateral being a 6 year old entry-level mountain bike ;) But Erik is just that nice a guy and I think he's a great guy to do business with.