Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater

Sat, 30 Jun 2012

Doing It Right: Vetta RT255L Bike Computer

By way of setting expectations: I am a daily bicycle commuter, usually riding between 10 and 20 miles per day depending on what errands take me out of the way. I ride at all hours and in all weather (including snow, thanks to some Nokian Hakkapelliita studded tires). I don't ride for pleasure, I don't race, I rarely ride with anyone else, I'm just getting from point A to point B. This review reflects that reality.

Introduction

When I was a teenager, riding my cheap Nishiki 10-speed around before I got a driver's license, my grandparents got me an unthinkably cool gift for my birthday one year: a Cateye Cateyemate bicycle computer.

This was the 80s, and I recall having been aware that bicycle computers existed, but I imagined that they had to cost hundreds of dollars. I have no idea what the Cateyemate sold for at the time, but it was, to me, an extravagant gift, and I was thrilled to strap this shining jewel of high-tech to my bike. I logged many a mile on the Cateyemate.

Of course, this presaged things to come. Electronics were getting smaller, and it wasn't long before bike computers were commonplace, and we're now at a point where the cheapest bike computers cost less than the shipping charge necessary to receive them. That $5 bike computer does more than the Cateyemate ever did.

Scroll the narrative timeline forward to the early 2000s. I'm riding a motorcycle every day, and decide I really want a clock on my bike. I don't recall where exactly I got the idea, but somewhere online, someone suggested the Sigma BC800 as a good motorcycle computer, which just happened to have a clock. Aha! thought I, a clock, and an accurate speed readout (my bike's speedometer was well known to be inaccurate). Done.

The Sigma was a good choice, but it had this weird habit that I never got used to: when it woke up from its sleep mode, it always displayed speed and trip distance. No matter what the adjustable lower display had been set to before, it woke up to trip distance. I wanted the clock, so I'd always click the little button five times to get it to the clock. It was annoying, but workable.

Then, in 2006 and 2007, when I shifted back to bicycles for daily transport, I stuck with the Sigmas, because better the devil you know, etc. Still, with increasingly sophisticated models, Sigma insisted on this weird habit of waking up on trip distance. Otherwise, they were great, but this one issue bugged me.

So, when I got my new Surly Disc Trucker a few months ago, I decided to check out the field, and find a computer that more closely met my needs. I wanted to not have to switch modes every time the thing turned on. After a bit of looking around, I added to my list that I wanted to also have a clock displayed at all times, with the option to show some other number, and if I could possibly swing it, I wanted a thermometer.

My Sigmas had all been wired units, and that choice felt right to me: wireless units look to have occasional reliability problems, and it means more batteries wasted, and potentially more weight, depending on the system. The search eventually led me to the Vetta RT255L:

On paper, this hit all my points: two switchable display areas (the top and bottom sections), one of which could be left on clock all the time if I wanted; wired; no serious design flaws (more on that later); appeared to stay on the previously selected mode; and as a bonus, it included a backlight, something I've occasionally wished for. The fact of staying on the previously selected mode is actually something that no one said. The manual didn't say anything about it, online reviews didn't mention it at all. I eventually had a find a store that carried them (and they only had a sample set from the distributor, having decided not to sell them), and test it myself.

In my search, I went through a number of other likely candidates, although I've already forgotten exactly which they were. They were all promising looking, but had some fatal flaw. This one only came in wireless. That one only had one display section. This other one had a reputation for a terrible mounting system. There was one which required, when changing the time (such as you might do twice a year for daylight savings time) that you re-enter every setting on the computer: wheel size, odometer, time ridden, etc. Talk about cumbersome, and how often would I forget to write down those numbers before launching into the time change procedure? Fail.

Installation

Installing the RT255L was pretty straightforward. Installing bike computers usually is, but occasionally I've seen reports of difficult installs.

The mounting bracket, which looks pretty sturdy (one review claimed that the computer flew off the bracket whenever you pressed a button) attaches to the handlebar with supplied zipties. It's a very secure-feeling mount, attaching solidly to the handlebars. Compared to the Sigmas I'm used to, which use a large O-ring to fasten the mount to the bar, it feels welded to the bike. In a crash-prone bike, the solid ziptie mounting might well be a deficit compared to the rubber band mount, though.

The included wheel magnet has a metal spoke mount with a setscrew to fix it in place. Although it feels solid, I found myself wondering if I was doing damage to the spoke. A poorly finished setscrew end surface could easily score the spoke, which would lead to early failure. I repositioned the magnet a couple times, though, and didn't see any marks on the spoke.

The wheel sensor mounts to the fork leg with included zipties. The instructions include clear direction on how to align the magnet to the sensor, something which doesn't always make the cut in manuals. It's not intuitive, either, as most of the sensors out there are most sensitive somewhere other than the center of their mass. This sensor includes a molded-in line showing its most sensitive area, and the kit contains a little rubber cap with a conical point on it that goes over the magnet, and is used to precisely align the magnet to the sensor. With the rubber cap on, you have a clear indication of both distance between magnet and sensor, and radial alignment along the spoke. I really liked this extra thought given to the installation process.

Setup

One of the weirder selling points of the RT255L (and its brethren in the Vetta lineup) is that you can swap faceplates. This allows you to change the color or appearance of the fascia around the display. I'm sure this will appeal to someone, but I just wanted a black computer. The RT255L comes with a red faceplate installed on the computer, and a clear faceplate (which results in a black appearance) in the kit. But if you really want a bright pink bike computer, they sell a faceplate for you. Curiously, the faceplates are hard to find except on the Vetta website, suggesting I'm not the only one puzzled by this particular choice.

Setting all the options in the computer is fairly straightforward, assuming you have the manual at hand. If you don't have the manual with you, half the options are complete head-scratchers, with obscure codes that aren't meaningful, relying on flashing icons to convey meaning. Fortunately, the manual is available online, so even if you lose your paper manual, you're not completely lost. The paper manual is one of those giant sheets of paper folded a million times, with the instructions repeated in 5 different languages. It's laid out well enough, and I didn't have any trouble following the instructions, but the text is tiny, and it seemed like the instructions might have been translated from a different language into English.

The setup menu does give you the option to input your own odometer and time-ridden values, features which matter to me, as I keep a running odometer on my bike when possible, to track maintenance and bolster my "biking badass" self-image. I don't know if the memory will disappear upon changing the battery. The computer uses a standard CR2032 battery, so you won't have any trouble finding replacements.

The setup menu includes a lot of stuff I didn't care about, like freeze frame memory, and lap timing and probably other stuff I've already forgotten. They didn't matter to me, as a commuter, so I skipped over them.

The computer includes a database of wheel and tire sizes, so if you don't want to measure your wheel, you can get close by selecting your bike's wheel and tire size. When I did this, I found my reported speed to be 6% over reality (judging by distance ridden) when compared to a GPS. I ended up measuring my tire's circumference, and found it to be 20mm or so shorter than the database value, but this may only be a factor with my individual setup.

One of the weirdest features of the Sigma computers is that they determine whether your clock is 12h or 24h based on whether you're using MPH or KM/H. The RT255L doesn't have this failing: it just asks which kind of clock you want. This is so much better -- I want to use a 24h clock, whether I'm looking at miles or kilometers.

Using It

In daily use, the computer comports itself nicely. It wakes up in the mode I was last in, so I leave it with the clock on top (this occasionally changes when I accidentally bump the display-1 button), and usually with trip distance on bottom. I occasionally switch to average speed, but just find that depressing -- my last computer was, unbeknownst to me, set to be 6% optimistic on speed and distance, and there's nothing quite as demoralizing as discovering that what you thought was a 13.x MPH average speed is actually 12.x.

Unlike the newer Sigmas, the RT255L will allow you to see all the numbers while you're moving, including odometer. This struck me as a weird choice on Sigma's part, and I'm glad to see Vetta's not following the lead. Honestly, reviewing computers from different companies, I'm not sure they're paying any attention to each others' product lines, they're so different.

Resetting the trip values on the RT255L is a little strange. Rather than using the prominent 3 button (which goes unused in my daily life, but perhaps it's for one of the features I don't use), you have to set the lower display to trip distance, then hold down the 1 and 2 buttons together for 3 seconds. Likewise, to get into the setup menu, you have to set the bottom display to clock, then press 1 and 2 together for a few seconds. This is all rather unintuitive. It's always a tough call how to make this kind of thing work on something as non-standardized as a bike computer, but I like Sigma's dedicated buttons better.

When you reset trip data (trip distance, average speed, time ridden), you reset it all at once.

The backlight has a neat feature, where you can set time limits during which the Auto Backlight operates: press any button and the backlight turns on. Outside those times, the backlight only turns on via the dedicated backlight button.

One thing I don't like in daily use is that the update rate on the computer is pretty slow. It feels like the display only updates every second or two. I'm sure this is done to save battery life, but it means I've looked down immediately after stopping to see 5 MPH still registering on the display for a second. In a world of ever-increasing responsiveness and speed, this feels like a step backward.

A feature which feels related, but isn't, is that the average speed only updates as frequently as the trip distance changes. Since the trip distance is measured (and apparently stored) in tenths of your selected unit, this means that average speed updates once every 528 feet, or once every 100m. It's not a big deal, but it's a bit surreal to look down at the start of a ride, and see that your average speed is 0.0 despite the fact that you're riding along at 16 MPH.

I also find moving to a 0.1 mile resolution on the trip odometer a bit disappointing after having 0.01 mile resolution with the Sigmas. It's a minor quibble, and not one I worry about, but it's there. I'm a precision freak along with being an accuracy freak, and reducing precision by an order of magnitude troubles me vaguely. I could increase resolution by going to metric, but the odometer stores itself in your current unit, so if you switch back and forth between the two, the odometer will go a bit crazy (if you ride in MPH for 500 miles, then ride in KM/H for 500 km, the odometer will read 1000, no matter if you set units to Metric or US).

If I were designing a computer (and I gave this some thought, but discarded it as being too much work), I would run and store everything internally as metric, and if the user was mad enough to request MPH, they'd get converted values. That is, in fact, how it works in my Air Data Instrument, although it doesn't have any persistent storage.

Conclusion

Having now ridden several months with the RT255L, I'm pleased to say that it's met all my requirements, and I recommend it. Here's what I like and dislike about it:

I should note that I bought and installed my RT255L; no one is paying me for this review. I've never used a Vetta computer before, and I have the impression they're not very popular, so I wanted to share my experiences with other bikers who might like the same things I do in a computer.

Posted at 13:26 permanent link category: /bicycle

Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater