200k Mixed-Terrain Brevet-style Ride this Saturday, July 19th

In case anyone's interested (and apologies for the late notice), a few
guys from my rando club are planning to unofficially ride a
newly-proposed 200k mixed-terrain ride this coming Saturday.... The
route starts in San Francisco's Marina district, crosses the Golden
Gate Bridge into the Marin Headlands, winds around Mt. Tam, then takes
you out towards Olema via Bolinas Ridge, back through SP Taylor Park
to Fairfax, then the abbreviated Paradise Valley Loop, to Mill Valley,
up Old Railroad Grade to West Point Inn, then back through the Marin
Headlands and back across the GG bridge. 60/40 split between pavement
and fire roads/trails.

+++

Saturday 07/19, 6:00am: La Ruta Loca Randonnee, a 200k mixed terrain
route. Meet at the Marina Safeway in San Francisco.

This is a *very* challenging ride, it has ~13-14k feet of climbing, ~
40% of the route is done on fire roads. The updated cue sheet can be
downloaded from http://bike.duque.net/ride-calendar.htm (select La
Ruta Loca Randonnee). If you come please make sure you are truly self
sufficient, we cover some remote areas. Also make sure you pack enough
food and liquids. Front & rear lights are probably a good idea.

Please note this is NOT AN OFFICIAL SFR or RUSA SANCTIONED EVENT, it
is just a harder-than-normal group ride that we'll try to do following
brevet "rules" (13.5 hour time limit, controls, etc.)...

+++

Unfortunately, I won't be joining in due to familial obligations.

My Next LED Bike Headlight Project

Not that I don't have too much to do already, but I've been irrationally obsessing over LED bike lights lately. I say "irrationally" because it's mid-summer where I live and the daylight lasts a good long while, making bike lights mostly unnecessary for me right now. I know that will change soon, though. (I should also be focusing on work, and at least a dozen other things, but I digress...)



Part of my light-lust is being fueled by the recent introductions of a couple of commercial dynohub-powered lights, namely the Schmidt Edelux and the Supernova E3. Both of these are attractive lights, and are reputed to be very bright. However, they represent one problem inherent in current LED-based bicycle lights: the fact that technological improvements often happen faster than product development life cycles.


What do I mean by this? Both of the lights above are based on LEDs that were state-of-the-art six months to a year ago. I don't know for certain, but I'd guess that both lights are based on Cree 7090 XR-E LEDs. The efficiency of these LEDs, ranked by their bin codes, improves constantly -- caught up in a sort-of arms race with other LED manufacturers (Luxeon and SSC), Cree seems to produce ever-higher bin codes every few months. Since it takes many months (to a year or more) to imagine, develop, prototype, manufacture, and ship a commercial product, what this ultimately means is that the commercial bike-lights you can buy today aren't using the best components available now!


Additionally, the Edelux and E3 are both single-emitter (one LED) lights. While these designs may be brighter than their halogen-incandescent predecessors, many folks are still choosing to run multiple lights on their bikes for increased output. At over US$100 each, these lights aren't cheap, and mounting two is even more costly. Why duplicate things -- I don't see the need for the extra lamp housing, wiring, switch, etc. required by the second light unit? Why not simply make multi-emitter dynohub-powered lights, with two (or more) LEDs in a single casing? This adds only the minimal cost and weight of the extra LEDs, and is the option most DIY projects take.


Furthermore, in addition to advancements in LED efficiency, new designs are becoming available: multi-core LEDs are the new thing. These emitters basically combine four diodes into a single device with the same footprint as a single-emitter LED (analogy: think four filaments in a single incandescent bulb), quadrupling the light output!


So, my next bike light project will involve getting a dynohub front wheel, and building either a three or four LED light head or a lamp based on a quad-core LED. I'm not sure when I'll get started on this, but the results should be brighter than what I can buy "off the shelf" right now! Plus, I will no longer have to futz with the batteries my other light requires...

Going Nowhere Fast!

Kogswell 700C P/R -- Long Term Impressions

I've now ridden just over 200 miles in just under two months on my Kogswell 700C P/R bicycle, so I feel qualified to offer up some longer-term impressions of the bike.

First, because I don't think I've done so before, I'll offer up a detailed component list:

Frame: Kogswell P/R, 59x700C (S/N: CB70W0093)
Fork: Kogswell 700C, 1-1/8 steerer, 58mm offset (expected ~42mm trail)
Rims: Mavic MA-3 - 32 spokes front, 36 spokes rear
Hubs: Shimano XT
Spokes: Wheelsmith 14/15g
Tires: 700x35 Panaracer Pasela
Pedals: Shimano SPD PD-M515
Crank: Shimano Exage FC-M520B, 175mm/24-36-46
Chain: Sram PC971
Cassette: Shimano 9spd 11x32
BB: Shimano UN-52 113mm
Front Derailleur: Shimano DX
Rear Derailleur: Shimano Deore 9spd
Shifters: Shimano bar-end 9spd
Handlebars: Trek System 2 44cm
Stem: Kalloy threadless
Headset: Kogswell (included w/frameset)
Brakeset: Avid Shorty 4 w/Koolstop Thinline salmon pads
Brake Levers: Shimano 600
Saddle: Terry Fly
Seat post: Zoom 27.2mm
Accessories: Nashbar front rack (modified/customized) with Performance TransIt Pro DX Handlebar bag, Velo-Orange 49mm fluted alloy fenders, Velo-Orange alloy bell, Zefal HPX-4 pump, Performance Forte Terra Lite Stainless MTB Cage (2), SI 90 computer


I've previously written about my initial impressions of this bike (see also), and my longer-term experiences mostly reinforces those first thoughts...

I still really like the fat 700x35 Pasela tires! In fact, I think the bike's strongest suite is the fact that it'll fit these tires with fenders...not many bikes on the market today can duplicate that.

Overall, the low-trail thing has been something of a disappointment, in that there's just not that much explicit difference between this bike and other non-low-trail bikes I've known. Sure, there's a difference, but it's so subtle that if I'd not known what to look for beforehand, I wouldn't have picked up on it. The P/R might hold a straight line at lower speeds somewhat better than other bikes. I haven't noticed any advantage while riding through cross-winds. The bike is definitely confidence-inspiring while riding through fast, swoopy downhill curves -- but that may be due to the fat grippy tires as much as anything else (I need to mount those tires onto another bike and compare). Low trail geometry is supposed to be beneficial for frontal loading of a bike, but I've been frustrated on that with this bike (more on that later). Does it plane? It might -- I was riding up a favorite climb with a friend recently, and I was pedalling at a fairly easy effort since my companion had dropped back a bit. He later claimed that I was ascending the hill at a strong clip, which suprised me because I was in fact trying to go slow to wait for him to catch up!

The biggest problem I'm having with the bike currently is the fact that it tends to shimmy fairly violently during no-handed riding. When I first began riding the bike, I purposely loaded it up "wrong" because I wanted to begin the experience with a familiar set of parameters -- I mounted my usual small, lightly-loaded handlebar bag up front to hold food and extra clothing, and a midsized seat pack behind the saddle carrying heavier items like tools. When riding no-handed, the Kogswell shimmied a bit with this front load, but I attributed that to the fact that the handlebar bag (a Rivendell/Baggins Candy Bar bag) non-rigidly straps and ties onto the handlebars and as a result, tends to swing a bit relative to the handlebars (this bag actually causes a bit of shimmy on two of my other bicycles as well). One of the key characteristics of a classic low-trail randonneuring bicycle, which the Kogswell P/R attempts to emulate, is its ability to carry a front bag while maintaining excellent handling and stability. In fact, it's argued that the front bag helps to reduce a rider's overall brevet times because tasks like eating and adding/removing a jacket can be done on the moving bike, since the cargo compartment is easily accessible. Obviously, to do these things a rider must be able to comfortably ride his/her bike no-handed. As an aspiring randonneur, I added a front rack and bag to my bicycle, but I was dismayed to find that the shimmy problem only grew worse, in spite of the fact that the bag is rigidly attached to the rack and bike!

Kogswell has produced two versions of the P/R frameset. The first version used oversized (OS) frame tubing and was powdercoated a custard-yellow color. While these frames were generally excellently received, some argued that they were too heavy and the ride was too stiff. To that end, Kogswell modified the design for the second production run, and the result is the black frameset using standard diameter, thinner-walled tubing. From this posting to the Kogswell Owners List:

> Is there a summary anywhere of the differences between the first and
> second batches of P/R's?

The down tube changed from 31.8 x 0.6 x 0.9 to 28.6 x 0.6 x 0.9.
The top tube changed from 28.6 x 0.6 x 0.9 to 28.6 x 0.5 x 0.8.

There has been some discussion since then that the new design might've taken things a bit too far -- that low-trail geometry coupled with light-gauge tubing is a recipe for shimmy. At this point, I'm tending to agree with that statement.

My handlebar bag and its contents (map, pen, first aid kit, tool kit, spare inner tube, small digital camera, jacket, small padlock and thin cable, food) weigh 8-9lbs. Assuming a weight of one pound for the front rack gives us approximately a ten-pound front load -- not at all atypical cargo for a randonneuring bicycle. Yet the bicycle shimmies profusely when riding no-handed at speeds of 15-18 mph or more. The bike rides very nicely and handles quite well during normal riding, but I simply cannot ride this bike no-handed for any distance. (For the record, I am able to ride any of my other five bicycles for quite some distance without hands on bars. Also, for the record, I weigh around 145 lbs., so it's not like I'm overly stressing the frame itself.) A recent thread on the Kogswell list prompted me to conduct some experiments of my own...

First, I checked the tires' pressure and ensured that they were inflated to 60 psi (according to my pump's gauge, which admittedly probably isn't terribly accurate) and remounted the handlebar bag with the typical contents. I was able to duplicate the findings of my previous ride, namely that strong shimmy occurs when riding no-handed at around 15 mph. Next, I removed the front bag, and discovered that a slight shimmy occurs now at around 18-19 mph. Third, I reinstalled the bag, and increased the tires' pressure to 75 psi -- again a slight shimmy occurred around 18-19 mph. Fourth, I replaced the front wheel with a similar wheel shod with a 700x28mm Pasela tire inflated to 85 psi -- and the result was similar to #3 above. Fifth, I attempted to tighten the bearing adjustment on the headset, but that didn't seem to change anything.

Finally, I decided to try the same front load on another bicycle entirely. I mounted a spare front rack on my mid-trail (59mm) Nishiki Sport and attached my handlebar bag to the rack (see photo). I expected this bike to ride like crap with this front load, but in a short test ride I was surprised to discover that it wasn't actually all that bad. In fact, it wasn't significantly different than how the Kogswell felt with a front load! AND that bike didn't shimmy. At all! Ultimately, this makes me wonder if my entire low-trail experiment is a failure!?! There's one last thing to try...I have a second fork with more offset (67 mm), intended to produce around 32 mm of trail on this bike. I need to try that and see what the effects are.

Stay tuned....

Low-Cost Handlebar Bag + Front Rack Project

Another rack shot
Originally uploaded by jimgskoop

Following up on a previous post about budget front-rack bicycle bags...

I really like those classic Berthoud bags and shiny Nitto racks, but those accessories don't come cheap. For cyclists on a budget, or especially those of us simply curious about trying out a front bag plus rack, there's no real entry-level option. I wasn't about to drop upwards of US$150 on a combination that I wasn't even sure I'd like! Since I already had a front rack, and I knew that passable modern handlebar bags could be had fairly cheaply (under $35), I figured there must be a DIY option...

The bag is a cheapy from Performance, while the rack is the infamous cheap front mini rack from Nashbar. I modified the rack by chopping off about 2cm from the lower legs and re-riveting the mounting L-brackets to some new holes I drilled. The rack now sits lower, closer to the top of the wheel, which is better both aesthetically and functionally, since it locates the load lower relative to the bike. I also tossed the rack's wimpy-thin steel mounting strap, instead using some thicker aluminum stock (3/4" x 1/8") to fasten the back of the rack to the fork crown. Finally, I fabricated the "decaleur" out of more aluminum stock (1" x 1/8"), resulting in a bracket that runs from the rear of the rack, up to the lower handlebar clamp bolt on the stem. The bag's quick-release plate, which would normally get clamped to the handlebars via a couple of u-shaped brackets, is instead fastened to this upright bracket. The bag still easily clips on and off its mounting plate, except now the bag sits on the rack instead of waving about up high in front of the handlebars. Like most similar bags, this one has an internal frame & plastic stiffener to maintain its shape.

The total cost of this system was around $50 (I already had the aluminum stock, which is available at most good hardware stores/Home Depot/Lowes/OSH/etc.), and took me one late evening to build. In retrospect, I think I subconsciously drew inspiration from the front rack on the bicycle pictured on the cover of the book The Golden Age of Handbuilt Bicycles.

More photos



Additionally...

There may be something to this low-trail business after all.... That bag, plus its contents, weighs around 8lbs according to my bathroom scale. So figure the total load of bag+rack at around 10lbs. Although it noticeably affected the steering of the bike -- making it feel somewhat slower -- it didn't adversely impact the handling of the bike. I don't have much experience with front-loading on a bike (see this and that) but I can say that the Kogswell P/R with this handlebar bag felt better than either of those previous experiements. I even rode the bike off-road and things felt generally OK! More experimentation needed, obviously....

Hmm...maybe he needs some low-trail?!

(via cycleicio.us) Ouch. Maybe this wouldn't have happened if he'd been riding a low-trail bicycle?

Losing Focus

Confession time! I didn't ride this weekend. I didn't ride the weekend before that, either (but I was out of town, so I do have a valid excuse). On top of that, I haven't done a big ride since mid-April. I did ride 52 miles to work on Bike to Work Day in mid-May, but that route was entirely flat so it hardly counts...

I was going to ride on Saturday, but had some familial obligations so I shifted it to Sunday. I had intended to wake up, gulp a quick breakfast, swap some tires around on the Kogswell, and head out for a half-day's saddle time. Instead, that Sunday I woke up and ended up fettering most of the morning and early afternoon away in front of the computer, lulled into a YouTube stupor, blasting old Peter Gabriel videos (more) on the PC speakers. I'd always loved PG's music in high school and college, and re-finding this stuff was like opening a lost Christmas present... I also learned that his excellent bassist is Tony Levin, and Tony invented a nifty bass-playing gizmo called Funk Fingers. Oh Interweb, curse you for being a most random and excellent time-waster! My wife got pretty exasperated..."I thought you said you were going out for a bike ride?!?"

I know that everybody needs an occasional day of doing nothing, but I'm not sure that's what's going on here. Generally, I eat, breathe, (over)think, and sleep all things bicycling -- too much so. So why then, given a perfectly nice day and a solid chunk of time to go outside and enjoy it, am I entirely unmotivated to go out and ride? For the past several weekends, getting out on the bike has been like pulling teeth, and I just don't understand it! It seems that, unless I have confirmed plans to meet folks for a ride at a specific time, that I just end up lallygagging about.

Ironically, I do know that the new Kogswell is part of the problem.... Not that it's a bad bike, but it (or I?) needs lots of tweaking, adjusting, and experimenting to figure out this low-trail thing. So that adds some mental overhead to riding -- instead of just heading out for some miles, I've got to futz with the bike and keep mental notes of what works and what doesn't. Plus, I don't yet feel as if I've worked out all the bugs, so I'm not confident enough with the bike to take it on longer or mixed-terrain rides. I've been tempted to just ride other bikes, but if I do that then I'll never "finish" the Kogswell.

Tangent: One of the downsides of owning lots of bikes is that one or more of them always needs some kind of attention: repairing/fixing/cleaning/adjusting/whatever. I'm half-tempted to box up a few of my bikes and shove them in my attic or something to reduce my "mental clutter"!

It's like when I was in school, and had a big exam the next day: I'd find any excuse (even laundry or housecleaning) to put off studying, procrastinating until the last minute and then frantically studying all night...

Maybe I need some psychoanalysis, I don't know. What I do know is that, unless I find some motivation, I'll never sort out the Kogswell, and I'll never be in good enough shape to attempt (let alone finish!) the La Ruta Loca mixed-terrain 200k on July 19th!

What tips or tricks do you use to stay focused on riding?

More Low-Trail Experimenting...

Kogswell Test Rig
Originally uploaded by jimgskoop

To the dismay of my other bikes, lately I've been mostly riding my Kogswell 700x P/R. The adjacent photo shows how I've been outfitting the bike for the various test-rides I'm doing. I recently lowered the saddle 1cm (but then raised it ~5mm during the last ride), moved the saddle forward ~2cm, switched to a longer 120mm stem, and also tried 700x30 tires inflated to 75psi. The first set of tweaks are all aimed at dialing in my position on the bike; the tire swap was done to learn its effect on low-trail handling characteristics -- I had 700x35mm tires @ 55psi mounted previously, but I was advised to try 700x30mm tires @ 75psi since I wasn't feeling the low-trail love. I can say that the narrower tires do seem to reinforce the expected characteristics somewhat, although I definitely prefer the ride of the larger tires, especially during fast twisty descents.

After swapping the tires, I took the bike for a ride late Saturday afternoon, in cool and windy conditions. I rode across the Golden Gate Bridge and down into Sausalito, picking up the Mill Valley Bike Path as usual. The path is usually beseiged by winds in the afternoon, possibly due to the shifting tide and/or the fog rolling in -- one of those "Sheesh there's a headwind in both directions" occurrences that seem common in the SF Bay Area. Saturday was no exception, and as I pedaled along, I noticed that the bike felt "interesting" in that, as I got nudged left and right by the blustery breezes, the front end of the bike seemed to exibit a self-centering effect. It felt uncannily like the invert-a-broom-and-balance-it-on-the-palm-of-your-hand trick -- aka the upside-down pendulum. Pretty neat!

I left the bike path and climbed Camino Alto, one of my favorite hills. Due to the late hour, I turned around at the top and dropped back down towards Sausalito instead of continuing on towards Tiburon or Fairfax. The last time I rode down this hill on the Kogswell, the bike wore the 700x35mm Panaracer Pasela tires (at 55psi), and descending on that bike with those tires put a big grin on my face! For the first time ever, I felt hugely confident in the fast curves and rarely had to grab the brakes. Today was different, though, and the bike felt quite unstable. So much so, that as I dove into one curve, I though I'd overshot the lean and was about to go down, but in an instant I stopped panicking as I realized that no, the front wheel wasn't slipping out from underneath me, and the bike completed the turn and I emerged unscathed, but with a racing pulse!

Returning to Sausalito and back on the Mill Valley Bike Path, I remembered the many discussions on load distribution and how that may affect low-trail handling, so I stopped to shift some weight from my seat pack to my Rivendell Candy Bar handlebar bag. As I continued my ride, I noted that the front end indeed felt heavier, but I couldn't say whether the handling grew better or worse with this change (and that in itself may be a positive result!). Note that I've never done this test on any other bike, so the results here are inconclusive.

Later, I rode down to Fort Baker to check on the new resort hotel that's opened there. As I rode past, several times I looked back over my shoulder to check out the grounds and the rennovated buildings -- and, certain that the bike had wobbled and lost its line, I turned my head forwards again to find the bike pointed exactly where I'd left it. Pretty cool!

I left Fort Baker and climbed up towards the Golden Gate Bridge. By now, it was pretty late in the day and the wind blowing over the Golden Gate was very strong. As this air blows over the bridge, a curious swirling pattern is generated as the breeze is split by the bridge's two support towers -- and riding around them at this time is always challenging. I'm hoping that the Low-Trail Effect (henceforth: LTE) and its reported resistance to cross-winds will come into play here, but so far I've been disappointed. In fact, on this ride I actually got knocked off my bike by the blasting wind and had to stop, put a foot down, and then dismount and walk my bike around the pylon. Whether I'd have fared any better on another bike, I don't know...

So, conclusion-time: I think the skinnier tires amplified the LTE somewhat. Presumably the added pneumatic trail from the 35mm tires was cancelling the LTE, so the narrower/harder 30mm tires minimized that issue. In spite of this, I will definitely be going back to the 35mm tires -- they just feel so much better, especially on twisty downhill roads! I also definitely want to test the bike's other fork -- currently it's built with the 58mm offset fork (expected 42mm of trail), but I've also got a 67mm offset fork (expected 32mm of trail) -- that should give me a better dose of LTE with the 35mm tires. I need to ride one of my other (high-trail) bikes and try the heavy bag up front to see what effects that'll impart. Finally, on an unrelated note, I want to lower my handlebars 1-2cm since I think they're still too high, most noticeable during out-of-saddle climbing. I may also want to try a set of narrower Nitto B115s; I've a feeling those would be the perfect 'bar for this bike.