Archives for the month of: November, 2013

Riding long distance on various cycles I have learned a few things about how a bike handles, how to be comfortable, and a notion of what planing might be. Rather than spend some time on a dear diary ride report or a lampoon of the alleged leaders of my past time, casual distance cycling, I will attempt to share something that might be useful to others and help them understand some of the more subtle aspects of cycling.

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Geometry, low trail vs high trail

The difference between a low trail and a high trail cycle can be as little as a thumb width, but even a thumb width in fork rake or chainstay length can make a significant difference in the way a cycle reacts under a rider.

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 Bicycles turn, when moving at a speed higher than a running pace (10mph) by leaning, not by turning the handlebars. Riders instinctively do this when they employ the technique of riding with their chin pointing where they want to go or simply looking where they want to go. Deliberately using body weight to turn a cycle is known as steering with your hips. High trail cycles resist the lean of the cycle and through caster in the geometry (like the front wheels on a shopping cart) the high trail cycle is designed to self-right and not lean very easily. To counter the self-righting action of the caster the rider will place a fair amount of weight on the inside handlebar when turning (I call this ‘pushing the front’).

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 Low trail cycles do not have as much caster in the geometry, are not self-righting, fall easier, and thus turn easier. To damp the easy turning of a low trail cycle, the weight of handlebar bag works nicely, and is handy to carry things too.

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 A low trail cycle also counteracts the gyroscopic effect of a large 40MM+ heavy tire when turning. A heavy tire will cause the cycle to track straight, rather than lean or turn. High trail cycles with heavy tires (or heavy front loads) can counteract the gyroscopic effect (or the weight of a load) with wider handlebars.

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 Low trail cycles do not react to steering inputs at low speeds compared to a high trail cycle. One way to notice this is watching cyclists start riding from a stop light. A low trail cycle will tend to track straight, while a high trail cycle will tend to track from side to side as the cyclist gains speed and stability. This phenomena is also quite apparent when cycling in a group at night and climbing a steep hill. Riders on high trail cycles will oscillate from side to side and the light from their head light will move from side to side. A low trail cycle will not oscillate, and will have a more steady beam on the road.

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 Here is a link to calculating the geometric trail of a cycle.

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Geometry, chainstay length

Shorter chainstays (15 to 20mm shorter) make for better climbing off road, and allow a rider to stand and still maintain traction. Shorter chainstays also result in a more abrupt chain line and will limit some gearing combinations, particularly the small x small combinations if the big ring is fitted with ramps and pins. To gain a few more gears in the small x small combination, turn the big ring around so the ramps and pins are on the outside.

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Geometry, wide handle bars vs. narrow bars

Wide bars allow for counteracting the self centering of a high trail cycle, but there are some side effects to a wide bar. More wind resistance; wide bars place your arms out in the wind, slowing the cycle. More perceived frame flex; wide bars have more leverage and can reduce the perceived lateral stiffness of a frame, particularly when carrying heavy loads. Increased reach to the bars; wider bars often require a switch to a shorter stem, to compensate for the increased reach out to the ends of the bars.

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Narrow bars are best used on low trail cycles as low trail cycles rely less on handlebar inputs for steering and more on body weight movements. Benefit of narrow bars are better aerodynamics and less perceived frame flex – that is, a cyclist can employ a frame with lighter tubes and not overwhelm the frame as easily because of the reduced leverage of narrow bars. Narrow bars will also cause a heavily loaded cycle to feel less flexible for the same reason, reduced leverage against all the weight.

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A touring cycle with low trail, narrow bars, with a front biased load will allow lighter tubes to perform more effectively, and feel more stable than a cycle with high trail, stout tubes, wide bars and a rear biased load.

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 Geometry, fitting handlebar bags and front platform racks

Handlebar bags, or the weight on a platform rack, should fit within the space roughly between the head tube and the front axle of the cycle. Placing the load in this area damps oscillations of the front wheel also known as speed wobbles and results in a more stable cycle when loaded than when not loaded. Placing the bag more forward or centering the handlebar bag over the front axle will not allow the load to damp oscillations and will reduce stability of a cycle and exaggerate steering inputs and make it harder to compensate for exaggerated steering inputs.

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low trail cycle with optimal load carrying space indicated with red box. A ten pound load can be carried in this space without negative effects on handling or stability.

low trail cycle with optimal load carrying space indicated with red box. A ten pound load can be carried in this space without negative effects on handling or stability.

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Low trail cycles with slack frame angles and the resulting increase in fork rake necessary for low trail, will have a larger space for a handlebar bag without negatively effecting steering inputs than a low trail cycle with steep frame angles. Low trail cycles with steep angles, with a smaller ideal load carrying space, require thoughtful rack selection and load placement to not upset handling balance. Berthoud bags which are narrow front to rear are suited to cycles with steep angles; most other bags that are deeper front to rear (ostrich, jitensha) are suited to low trail cycles with slack frame angles.

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high trail cycle with platform rack. load is well in front of axle.  A heavy load on this rack will exaggerate steering inputs and resulting corrections, causing instability. Looks cool, though.

high trail cycle with platform rack. load is well in front of axle. A heavy load on this rack will exaggerate steering inputs and resulting corrections, causing instability. Looks cool, though.

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Low trail cycles have a relatively large space for a bag. High trail cycles have little or no space and place much of the bag and its weight forward of the front axle. Weight forward of the axle exaggerates turning inputs and will result in an unstable cycle. Wider bars on a high trail cycle with a front load will reduce the influence of a front load, but at the expense of poor aerodynamics, increased reach, and more perceived flex in the frame.

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1950's French purpose-built cycle for front loads still places load too far in front of axle, but compensates with wide handlebars for leverage.

1950’s French purpose-built cycle for front loads still places load too far in front of axle, but compensates with wide handlebars for leverage.

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Top tube length also influences space for a handlebar bag indirectly. A shorter top tube, with the resulting longer stem length required for fit, results in a smaller space for a bag.

Review the first image and imagine the stem longer. The resulting space left for load carrying is smaller.

Review the first image and compare with this one with the stem made longer. The resulting optimal space left for load carrying is smaller.

For maximum space for a handle bar bag, a longer top tube and shorter stem is desirable. Generally the easiest way to get a long top tube on a cycle is to move one size up from what you might normally be fitted to, ie riding a 58×58 cycle when you would normally ride a 56×56 or a 54×54. Stand over height is sacrificed, but it is easier and more comfortable to sit on the top tube of a taller frame while waiting for a red light to change to green or for a friend who has stopped for a moment during a ride.

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Next up: Fitting yourself to a cycle and comfort on a cycle for rides of long duration.

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November! My birthday month and the time of year when darkness and rain drives the casual automobilist off the road and into simcity or the gym or the depths of their smart phone! Good times are ahead, starting with the Del Puerto 200, then a fun ride, and then the serious fun of the Davis Dart.

The Davis Dart was a highlight of last year, even though half of it was in a steady chilly rain. Two of the previous team mates were engaged otherwise, so I added my girl Juliayn to the roster and Henry, a friend of last year’s teammate Andrea, to the roster. Henry does many of our mixed terrain fun rides and has started to evolve into a randonneur under Andrea’s steady guiding hand. With the team selection taken care of there were refinements demanded of our route.

Last year we spent 30 soggy miles on bike paths out in the low rent exurbs of suburban sprawl and nobody really liked them much even though we were not out mixing it up with the uninsured pickups and the overloaded minivans and service vehicles in a hurry. I decided to trade safe but inconvenient and glass strewn bike paths for some mixed terrain riding through Black Diamonds Regional Park (a little sibling to Mount Diablo) and then a nice lunch at a mom and pop Vietnamese restaurant before a dash to the delta.

The official route for our Dart is the shortest distance between two points, narrow roads filled with late to the gym and late to the parole officer motorists and freeway interchanges traversed by texting truck drivers to satisfy ‘the official at RUSA’, or in the case of my fleche planning, ‘that guy in France’ that my team won’t take any short cuts along the route. I gave up explaining and pleading with officials that the shortest distance thing is not in the interest of the riders or having fun after my first fleche, so now when planning a route I just tell them what they want to hear and do my own thing when on the road. Now, please understand that I am allowed to add miles to the route; I just cannot shorten the route. If I want RUSA or ACP credit for the extra miles, I need to get a proof of passage to prove my team went farther. I have no interest in extra stats on my RUSA chart, so I just take the safe and sane unofficial way and everyone is happy.

Here is my official route that is acceptable for the rules, but not acceptable for a fun bike ride: http://ridewithgps.com/routes/2972853

Here is sort of what we did: http://ridewithgps.com/routes/3607446

Henry had to bail on the ride, so we four started and made our way up and out of downtown Oakland over the Oakland hills to the bike paths of the first layer of suburbs outside Oakland. We end the bike paths with a tunnel under a freeway section of our route. We ride on the freeway style road with high speed traffic, but there is a generous shoulder and despite Carlos’ complaints it is not bad. Andrea has been off the back from the start of the ride and I fear something is wrong because she is a much stronger rider than me. Turns out her rear brake was dragging significantly. We stop and I work on it and Andrea is much happier to be able to ride freely.

bike path goodness

bike path pampering

in the rabbit hole

in the rabbit hole

out of the rabbit hole

out of the rabbit hole

Soon we are in Black Diamonds! Gorgeous! Steep! I planned for 10 mph as an average speed but we were moving at 2 or maybe 3mph. The average speed was also reduced by mutinous team mates requesting stops to eat food, take pictures and other unnecessary luxuries. Lucky for me they had no trouble riding and complaining at the same time. When we went downhill, the totally atrocious trail surface beat us mercilessly and did not allow us any time gains from the climbing. Sure was pretty though.

up the hill

up the hill

stop for a rest...

stop for a rest…

stop for a photo...

stop for a photo…

down the hill...

down the hill…

Good bye Black Diamonds, we will be back.

Good bye Black Diamonds, we will be back.

We cut our losses and cut the Black Diamonds part in half and then get lost out in the boonies of exurbia until I recognize an intersection from last year and get us back on track. We are an hour down on time when we arrive at ‘downtown’ Brentwood and our lunch venue. ‘Downtown’ is a strip mall. It looks ok from Google Streetview, but very shabby up close. We start to make a bike pile outside the restaurant locking our bikes together, but the owner asks us to bring the bikes in – Thank you!

Food!

Food!

Somehow, no matter how depressing a town is, a Vietnamese Restaurant is always warm and  welcoming. Most of us get a big bowl of Pho, and Carlos gets pork chops. While waiting for the food I fill up everyone’s water bottles and re-fix Andrea’s brake which mysteriously tightened up again. Full of warmth, hospitality and encouragement from the owner we head to the Delta through some very depressed and depressing trash,  cell phone shop, and used auto lot strewn roads.

The Antioch bridge is deserted, and traffic steadily increases on hwy 160 to Rio Vista, our gateway to the delta and the wide pristine beaches therein. Before Rio Vista we pass another team that was correcting a mishap that was caused by a deep fissure in the road. California crappy roads are just as likely to have a longitudinal fissure in the road 4″ wide by 30 feet long as they are to have a pot hole.  Pot holes out here are from poor drainage, and the fissures are from subsidence and slides. The happy dog at the abandoned portion of Hwy 160 from last year was transformed into a snarling beast that I drove off with a squirt or two from my water bottle. Maybe I will bring a bone for it next year and it will be happy again.

on the hwy 160 bridge with mount diablo in the distance.

on the hwy 160 bridge with mount diablo in the distance.

narrow bridge on hwy 160

narrow bridge on hwy 160

To make up our lost Black Diamonds time we pop in and out of Rio Vista without a rest and arrive to wait for the ferry to the Delta. We meet a person who grew up in Walnut Grove and was revisiting her past. She was as happy as us to be back.

waiting for the ferry

waiting for the ferry

The delta is beautiful, the beaches are deserted and all ours and Juliayn ‘just ridin’ pulls us along at 17-18 mph that has us exactly on time when we arrive in Clarksburg to put on our reflecto gear a little before dark. Juliayn remains peppy and takes the Sacramento city limit sign from me. sigh.

corduroy beach

corduroy beach

grape vine beach

grape vine beach

tree curve beach

tree curve beach

beach combers

beach patrolers

pacific beach

pacific beach

goodbye delta, see you next time

goodbye beaches of the delta, see you next time

The quiet tree and bike lane lined streets of Sacramento and the excellent food at the natural foods co-op make me want to move there again. There is nothing like this place in all the bay area. sigh.

Carlos is antsy and we leave too soon and end up hanging at a gas station for 15 minutes so we don’t arrive too soon and get DNF’ed. We still showed up 15 minutes early.

At the finish I get to chat with all the rando friends and after some complaining that drove a few of my friends away we get served and get some food. We should have stocked up at the co-op for food and beer somewhere in Davis instead of relying on the finish venue. Next year I will be prepared to socialize, but not eat or drink.

Gabe and Todd

Gabe and Todd

Andrea, Thomas, back of Metin's head

Andrea, Thomas, back of Metin’s head

SFR RBA Rob

SFR RBA Rob

We and 35 other randos leave for the Amtrak back to the bay and in the scrambles for a place to hang a bike on the train we score the front car.  We assemble near a young mother and her crying little son and are boisterous enough to quiet the boy and scare away the pair to another section of the train.After an hour on Amtrak, we spend an hour on BART and we are home 18 hours later and much the richer for time spent on the road and together.

Thanks Davis Bike Club, thank you Eric S. and Dean A, and all the volunteers. Your efforts are appreciated, and we of the 16 teams that participated had the best of times.

Here are some Photos from a team mate
and of the BART ride home: http://www.flickr.com/photos/58323617@N08/10910541336/in/pool-37716093@N00

This ride is the season closer for the SF Randonneuring club and like our season opener that takes place in two short months, this ‘last chance’ attracts many new people plus old friends and can be just as much fun as a populaire, just a bit more work. 150 people signed up and for me, when that many people show for a ride I jump to the conclusion that 150 randonneurs equals 150 ways to get crashed, but nobody crashed not even Carlos (there was a whoopsie last year) so good job folks!

I show up a bit late because of BART maintenance keeping me on the train an extra 20 minutes and get to greet and thank Bruce Berg, the guy who helped to make this ride a standard on our calendar and proceed through sign-in procedures.  I get to say hi to Brian and Eric from the old Caz 300 while I stand apart from the group. The solemn SRF oath is given and then we all stand around for a while shivering until Rob starts riding and I follow.

By starting at the front of the group I can let everyone pass me and I have the chance to talk to some new people. Usually they start with a ‘nice bike’ (thank you for thinking so) and we start chatting. A young rider talks to me for a little while and I get the notion he is a racer so I point out Max to him as a solid fast rider who will give him a run for his money for the next 7 hours. I later heard he stuck with Max the whole way and that Max appreciated his company, so I did at least one good thing that day.

I ended up riding almost the whole way with two people I have been meaning to ride with for a long time – Manny and Irving. Manny is always happy and always strong and a noted photographer, and Irving is Irving.

Manny and Irving

Manny and Irving

I ride just a little faster than I like to on this ride for the first couple of hours, partly because a lot of it is a false flat downhill, but also because I want to get to Del Puerto Canyon where it is so beautiful, so different from what I usually get to see here in California.

typical Del Puerto experience

typical Del Puerto experience

more boring and typical Del Puerto

more boring and typical Del Puerto

At mile 19 of del Puerto I stop at Adobe Springs and drink some water even though I am not thirsty just because I can. Manny has long ago dropped me and Irving effortlessly riding and laughing with friends Gabe and Carlos way back at mile 5 give or take a mile. After a short refreshing pause Irving and I start the climb together but I am at the top a little quicker and take pictures of people summiting the climb until Irving arrives.

Eric from the old caz 300 is first

Eric from the old caz 300 is first

Francisco is next

Francisco is next

Wrench Science friends from last year are next

Wrench Science friends from last year are next

Willy speeds by saying he will beat me to the county line - and he does

Willy speeds by saying he will beat me to the county line – and he does

and Irving! lets go Irving!

and Irving! lets go Irving!

Riding the few rollers before getting to the next control Lee catches us and we get to catch up a tad before a break at the Junction Bar and Grill. The tavern keeps served up the food randomly and some like I, waited over an hour while others arrived and got food instantly. Last year I toted a 32oz mug for drinking and this time I brought it along again. While waiting I consume two mugsworth of beer and probably went through the several stages of grief while waiting the 90 minutes it took for my grilled cheese and French fries. Maybe I was entertaining to the others as I found myself passing through shock, disbelief, anger and acceptance, but I was probably just plain obnoxious the whole time. I refuse to apologize, but you can forgive me anytime you like.

languishing and starving at the old folks bar and grille

languishing and starving at the old folks bar and grille

a hearty thumbs up for the service and food

a hearty thumbs up for the service and food

Never again will I depend on the efforts of the befuddled seniors of the Junction for my food! I will return to my technique of last year and carry a large heavy sandwich filled with food security made with self-love and flavorful pampering. Maybe I will buy beer from the befuddled seniors if the line is short. Maybe.

Leaving the old folks control we get the added bonus of Steve H. and Jack Moonbeam in our group, but once the descending starts Steve and Manny drop away from us not to be seen until 10 miles later in Livermore where they are delayed by a difficult to repair flat visited on them by the Spirit of Randonneuring. Ha! The long wait at the junction stole all of the beautiful evening light from us for the long descent to the Diablo Valley on Mines Road, leaving us just the dregs of the gloam, reminding me of yet one more reason to bring my own food and not linger at the Junction.

Jack moons at the camera - Stylie!

Jack moons at the camera – Stylie!

Irving approves of the easy grade down to diablo valley.

Irving approves of the easy grade down to diablo valley.

Just as darkness takes hold we arrive at the finish in Dublin and enjoy some Starbucks hospitality. I get my mug filled with hot water for green tea, and to further warm my heart Irving presents me with my Stokens that I have earned for the day, and Manny thanks me for wearing a jersey with photogenic qualities.

hot tea and stokens

hot tea and stokens

Our group had talked about for going to a pub for dinner after the ride, but no one has that sort of ambition any more. Irving did point out the combination of a Bevmo and an in-n-out burger joint 500 feet from the finish that gets our brains churning for feeding ourselves next year in these food-that-comes-frozen-in-a-box wastelands. While waiting at the BART station for the train home and I realize Manny has gifted me with a Peek-a-pooh for my bike. Irving and Manny are very generous with their hearts and their possessions and remind me I can do better as a human being.

Farrah and I are happy to go home

Farrah and I are happy to go home

Goals met! I rode with the people I wanted to, chatted with a few new ones, reacquainted myself with a few old/new ones from last time, and learned an important lesson about feeding myself at the Junction.

Nice ride. Thanks volunteers and thanks SFR and Bruce.