Friday, April 27, 2012

Techie Tuesday: Mounting Helmet Lights

After crashing in Feb, I replaced my Bell Ghisallo with a Bell Volt, and have had to experiment a little to find good mountings for my summer lighting. The Blackburn MARS 3.0 taillight was pretty easy, and very similar, but mounting the Fenix LD01 flashlight in front, to use as a map light, and/or emergency headlight, required some innovating.
Overall, a pretty light and slippery lighting system. The Fenix starts in Med mode, and is switched by quickly twisting the front of the light to toggle it through its 3 settings. Med-Lo-Hi. Nice that that's a 1-handed operation!

MARS 3.0 taillight is offset 2.5" from the back of the helmet, which makes it visible except from directly ahead. Combined with the headlight, it makes it easy for motorists to figure out where I'm looking at night.

The Blackburn mounting system uses what is essentially a plastic hose clamp. It works very well with the addition of a wooden dowel as a "soft" spacer. No need to over tighten. Easy does it!

Mounting system is minimally intrusive on the human side of the helmet

Bug's-eye view of the Fexix LD01 "headlight"

At .5oz for the Fexix, and whatever the AAA weighs, this little guy (20mm) is 1/10th the weight, and 1/5th the size of most headlights, so it doesn't grab much wind, nor block your helmet's cooling vents

A little hook-side Velco stuck to the helmet, and then a Velcro wire bundle tie looped over the top, makes a nice soft, movable/adjustable mount for lighting the cockpit, and/or, the road.

The back of the flashlight body was wrapped in a 3" strip of soft rubber gripper, held in place with a tiny zip-tie. It was pillfered from another mounting kit. Hollow back aids cooling.

Detail of inside of Velcro mount. Note it is "clamping" on solid Styrofoam, so not compressing two unsupported slots together.

I left a small slot at the top of the flashlight uncovered when wrapping it with loop-side Velcro, to allow for better cooling. The light, if anything, tends to push air into the front slot, and suck it out of the rear slot, improving overall ventilation
Based on a suggestion made on, I inserted a LION 10440 cell into the Fexix LD01. It's very bright anyway, but the 72 lumens jumps to about 225 with 3.7 volts pushing it, instead of 1.25 volts. On the lowest setting it produces about the same light it's supposed to on the 27 lumen setting. On med, about 100 lumens, and I'm scared to leave it on high for more than a minute as it gets hot fast.

I'm going to experiment with this setup a little, but can't recommend it at this point. On low the 10440 cell only lasted 2.5 hours, so not much on endurance. I may try the medium setting with the flashlight in my freezer just to see if it's the LION cell's voltage regulation circuit that is limiting it's burn time, not power drawn. Happy trails!

Friday, April 20, 2012

Techie Tuesday: Mavic Open Pro - How Tough Are They?

It's been a little over 2 months since I crashed in the rain, ruining my custom built Mavic Open Pro wheel, laced with 32 DT Swiss Revolution spokes 2X to a Shimano Ultegra 6700 hub.

No wheel ever built would have withstood sliding 3-4 feet sideways at a 40 degree angle, at 15mph, into a notched utility cover slot. After rebuilding my wheel with a DT Swiss RR454 rim, with Revolution spokes laced 3X, I took a closer look at the OP, and think it stood up to a tremendous amount of damage with some remarkable results.
  1. None of the eyelets pulled through, despite tremendous damage to the rim
  2. The tire did not go flat, nor come off the bead
  3. None of the DT Swiss Revolution spokes broke
  4. None of the alloy nipples were stripped, with all the threading intact
While the advertised weight of the OP is 425 grams, it's measured weight is 440 grams, but even still, the RR465 is 465 grams, so the OPs are very light. I believe the 2012 OPs have lost 5 grams, weighing in at 435 grams now.

I went with the DT Swiss rim because I've had so many problems with SUP welds on my OPs. First, my custom-built Colorado Cyclist rear wheel's braking surface started to buckle right ahead of the SUP weld, and when they rebuilt it (at no charge) they were either vindictive about selecting a new rim, or I had very bad luck.

Without ever riding the replacement wheel, I took to to MadCat here in Sacramento and had Eddy inspect it for usability. As a result of photo consultations, and caliper measurements provided to Mavic, that wheel was rebuilt a 2nd time, again at no charge to me, as Mavic paid for everything. I am extremely happy with the OP wheel Eddy built for me. Even after sticking a heel into the drive-side spokes when I crashed, the spoke did not break, and Eddy charged me $0.87 to fix and true the wheel. Excellent customer service all around!

This front wheel jammed hard into the fork and front brake calipers, leaving some deep gouges on the inside of my fork, but, as you can see, the wheel held together, although just barely at the SUP weld. I think the rim strip was actually holding the SUP joint together, or at least, the small stress of removing it so I could unscrew each and every spoke to check for stripping, broke the SUP weld.
Very Egg-shaped, but still a cohesive object, and it held air for 3 weeks, until I carefully disassembled it.

Enormous stresses borne by this wheel are evident in the tearing of the Maxal aluminum alloy. Serial number front and center for the folks at Mavic, who I hope will have a look at this
Note the seperation of the sidewall from the rim here. About 1" (25mm) of seperation here was the extent of this mode of failure

Mavic's SUP weld plug. It looks like concrete, but I'm sure it's aluminum alloy of some sort. Note the "T-shaped" slot
The other, mating side of the SUP weld, with some kind of plastic alignment plug protruding. Note the massive amount of damage here. Somehow, it did NOT break all the way. Very, very impressive!

 So this brings me to some observations, and conclusions. First, all metal rims are going to have joints, so you can chose between sleeved joints and welded joints. Carbon rims have no joints. Advantage carbon. This does bring up an interesting option though - alloy rims with carbon joints. I'm thinking of something like an inch of ExoGrid structure.

Second, anyone that says DT Revolution spokes are weak, and break easily is lying, and I would encourage you to tell them they're speaking from ignorance if you read this claim, or hear it in person. Demand they show you proof, as I have done here.

Revolution spokes are so elastic they are virtually impossible to break. I bent one around the heel of my shoe, putting a 35mm indentation in it, and it still didn't break, and neither did even one of the spokes on this wheel, in spite of totally destroying the wheel and rim. Beyond that, the 300 stainless that most spokes are made of is so elastic it can stretch to nearly doulble it's original length before failing. Titanium spokes? Yes. Aluminum spokes? Absolutely! Butted stainles steel spokes? Never!

Wednesday, April 4, 2012

Techie Tuesday: Riding in Cold & Darkness

One by one I've attacked the challenges attendant with riding in winter, mostly those of riding in the cold and the dark, since it has been dry this winter, and I don't consider riding on the road safe with motorists looking through rain-spattered windows. A great litmus test for whether you've got your gear nailed, it will test you to the limit at times, but it's also been very rewarding. In Dec, and Jan I set a new PB for mileage, and then broke both of those in Feb and then again in March.

--- COLD ---

Before going any further, I should warn you that riding alone at night in the cold is dangerous, and very unforgiving. If you have a flat, or take a spill, or can't ride and make heat for any reason, hypothermia is almost a certainty, and that could be fatal if you're riding alone at night. 

There's an art to riding in cold, some finesse, endless clothing combinations to work out, and some thoughtful planning.

It's important not to over-dress, but rather, keep extra clothing dry, and in reserve. Overdressing just creates hydration problems, leaves you chilled and soaking wet, and with nothing dry to augment your protection, likely to make things worse, not better, if stopped in the cold. Always bring a foil blanket along in the saddle bag. It will make up for a few poor choices, or unfortunate circumstances.

A convertible jacket with zip off sleeves, a dry balaclava, a 2nd balaclava, 2nd vest, or leg warmers you can pull on over tights, can all save your life. Keep your legs warm at all costs. If they get cold enough to start cramping, which is a constant threat for me personally, you can't pedal hard enough to make enough heat to stay warm. Let your arms and core freeze if you must, but keep your legs and head warm.

Climbing out of the saddle on a steep hill is the best RX for warming up - if it's not already too late. The lower speed minimizes convective, motion-generated wind losses, while the extra effort of climbing out of the saddle maximizes muscle work – especially in your core. Cold legs that won't spin will still mash, and using the gluts and lower back draws on muscles that are hopefully still fairly warm.

The worst-case scenario is crashing and being knocked unconscious. You might well wake up dead, having succumbed to hypothermia while unconscious. Keep this in mind when planning your riding gear for the day, and have sufficient lighting to avoid rocks, sticks and debris.

Dressing right for cold weather riding relies on having an accurate thermometer, and a very deep pool of clothing to draw on. You can mix and match clothing to adjust for various weather conditions, but only if you have to have a good thermometer on the bike, and take note of those temps. (I'd buy a GOOD thermometer, masquerading as a cadence sensor, in a heartbeat. Garmin are a bunch of dimwits, and have added a thermometer so BAD, it's next to useless)

SMUD, our local municipal utility company, passed out some energy conservation kits last year, and part of that kit was a cheap digital thermometer which fits in my map clip perfectly. It reports to tenths of a degree, and seems as accurate as my more expensive household digital thermometer. It reacts in seconds to temp changes, unlike the Garmin 500, which has so much lag built in, it's almost useless for the 5 degree drops in temp when rolling down into a low draw along the river. 

Dressing for those transient cold spikes is important, because a couple of thousand yards of that kind of cold is enough to bring on cramping, and if that shuts down your legs, you're in serious trouble.

 Knowing where it's cold, and when, is invaluable in planning your clothing for the day. For example, upstream from Sunrise is about 5 degrees warmer than downstream, and since temps can drop as much as 25 degrees after sunset, I've taken to riding the cold part first, while it's still warm out, and the warmer part after sunset when temps are plunging. The more uniform temps make dressing much, much easier. (I set out in 75 degree temps recently, which became 79 degrees up in Folsom, and dropped to 52 a few miles from home below WBP. A 27 degree temp swing in 2 hours)

Besides temperature, wind, cloud cover, and humidity are significant factors. While temps typically fall 10-15 degrees, and as much as 30 degrees about 30 minutes before sunset, to an hour after on clear nights, overcast skies rarely allow temps to drop more than 5 degrees an hour around here.

In addition, very cold, clear nights are often created by cold, dry arctic winds here, and the dry wind greatly increases evaporative losses. These are the only nights I want to wear a jacket, which covers my armpits, because human skin tends to sweat even when cold to maintain a minimum surface humidity. (there was a lot of research into "vapor barrier" clothing in the late 70s, which I haven't read anything about lately, but it's for real) "Wind burn" is also more problematic in such dry air.

The biggest threat I've found from wind is quads quickly chilling until they start cramping, but to a lesser degree, this is true of all the leg muscles, and the feet and hands as well. The PI Barrier Balaclava does a good job keeping my face, forehead, and neck protected, but below 45 degrees cold, dry wind needs to be stopped with a helmet cover to prevent ice cream headaches and stiffness in the back of the neck.

There are lots of little changes that have to be accounted for as well. Powerbars I slip into jersey pockets are hard as bricks, so I've gone back to slipping them under the right leg of my bib shorts, against my skin. The foil wrapper helps keep my thigh warm to boot.

Water bottles, especially the Polar ones, become almost impossible to squeeze, but even the wonderful Camelbak bottles get hard to squeeze. You might also need to start your ride with warm Gatorade and an insulated bottle.

Batteries, especially NiMh batteries, don't work very well in the cold. They don't produce as much voltage nor store as much energy, as the voltage curve is shifted lower, and drops off aggressively after about 30-45% of normal durations. If you carry spares, an excellent idea, carry them close to your skin to keep them warm.

On the plus side, LED lights never have heat problems in the winter, requiring them to temporarily drop down to a lower setting. Also, running them at cooler temps may extend their lifespan somewhat. (although, 50,000 hrs is probably longer than you'll ever need them, as the technology keeps improving)

--- DARK ---

Planning for riding in the dark is much less an art, and much more straight science, than dealing with the cold. Dark just requires good lighting, although that did turn out to be a significant trial and error process. With the addition of the small Fenix E05 flashlight though, I'm pretty close to finished with lighting. With the G.I.T Lit plan, implemented as a 5-light system, you can safely ride anytime, anywhere, within reason.

The greatest danger after dark, is hitting something that SHOULD be lit, but isn't. Just after sunset there's a high risk of meeting other cyclists head-on who gambled on getting home before dark, and lost. Their bad - just make sure it isn't yours too. 

Other risks are gravel, stones, branches, road debris, trash cans, pot holes, cars coming out of driveways,  cats, dogs, wild animals (deer, especially bucks with big racks, freeze in headlights, and are likely to gore you, and they're never lit), rushing water, and low-hanging limbs. Think your lighting through carefully, but also, look around corners, and think around corners. Ask yourself if it's just unlikely, or really and truly impossible to encounter something. 

For example, it isn't very likely you'll encounter a drunk driver speeding down a bike trail at night with no lights on, but it sure isn't impossible. Metal thieves around here have been pulling out, or running over steel posts meant to prevent auto traffic from gaining access to the ARPT so they can steal guard-rails, signs, and even planking.

Being attacked and having your bike stolen is possible, as is happening upon the scene of a crime, and being an accidental witness. You might want to consider arming yourself. A S&W Bodyguard .380 is a good choice for that. Very small and light, and with a built-in laser targeting system.

You need to ride defensively to the extreme. You can't take anything for granted, and need to assume if they can hit you, they will. Cars coming out of narrow driveways can be unnerving at any time because you can't see the driver's face to check for the "Ahh Ha" look. At night, you'll never see the driver's face.

You have to rely much more on being seen and hoping the driver will keep you out of danger. For example, I've noticed at night that drivers will often wait at an intersection for a few seconds longer to "Sheppard" me across the intersection – interspersing their vehicle between me and crossing traffic – to help keep me safe. Cars will often wave you through an intersection as well, not wanting to risk a collision. If you've made them comfortable, and done your fair share to keep things safe, these kindnesses happen quite regularly, but it all depends on you being seen.

Little things help too. Like coming out into the middle of the lane at 4-way stops so you can see and be seen better. Riding down the center of a bike trail to avoid the debris and animal incursions is also a good idea. If you're going to have to take the lane to avoid garbage cans in the bike lane on public streets, do it early and robustly. Any following traffic should know, without a doubt, that you are taking the lane and are not going to move over for them.

The Fenix is the size of my little finger, but puts out 27 ANSI certified lumens of perfectly uniform light. Its light is so uniform and natural, that Velcro-ed to the top of my helmet, it's more like I can summon the sun. I magically have light when I need to read my Garmin, thermometer, gears, or highlight the 2" steel posts in the middle of the bike trail to keep metal thieves from stealing everything bigger than a dime. It's also nice to have my hands and bars lit, especially if using hand signals in traffic.

I have found one very unexpected benefit too – it cheers me up and keeps an otherwise depressing gloom at bay. Usually, within 15-30 minutes of sunset, I get a small case of SAD, and lose motivation. Quite to my surprise, having my cockpit, and the road beneath my front wheel lit, changes everything. The boredom dissipates with the darkness, and I find riding at night as invigorating as driving at night.


This is far from a complete expose` on winter riding, and you can expect I'll be back to edit this as I think of things, but the winter season is pretty much over now, so before I forgot all of these subtle lessons, I thought I should get this 1st attempt out there for the benefit of those just taking up cold spring riding. 

We recently had a cold snap and I was out riding past sunset, and the vibe was surreal. All of us die-hards were out there paying tribute to each other's steadfast determination to ride all year, through cold, dark, and occasional rain, day in and day out, thrilling at the incredible beauty seen by only a chosen few when winter sunsets just take your breath away. 

The feeling of camaraderie was overwhelming. Each rider was happy to be in the other's company, slowing down, reminiscing fondly, in a silent, shared recognition that their elite membership would too soon be revoked by warmer days ahead. It is with sadness that I say goodbye to my cold weather memories, a special fellowship of riders, and light to die for at sunset. A photographer's wet dream.