You can find the craziest bits of information in the strangest places.  There is no question that the late Sheldon Brown’s website is the go-to site for bicycle technical information on the internet.  However, clearly there are other repositories of cycling wisdom out there too.  What I didn’t expect was to find an extremely articulate article on wheel truing posted to – get this – the Mitsubishi Electric Research Laboratories website.  No kidding…  If the internet is great for only one thing, it is trails of breadcrumbs just like this.

The guy that wrote it – William S Yerazunis – is clearly a very intelligent guy.  His list of publications runs from information security, to computer science, to electro-mechanical and beyond:

Yerazunis, W.S.; Kato, M.; Kori, M.; Shibata, H.; Hackenberg, K., “Keeping the Good Stuff In: Confidential Information Firewalling with the CRM114 Spam Filter & Text Classifier”, Black Hat Technical Security Conference, July 2010 (Black Hat USA 2010, TR2010-064)

Shibata, H.; Kato, M.; Kori, M.; Yerazunis, W., “An Automatic Training Data Collection Method for Confidential E-mail Detection”, The Forum on Data Engineering and Information Management (DEIM), February 2010 (DEIM 2010, TR2010-065)

Slater, C.; Cleary, J.; McGraw, C.M.; Yerazunis, W.S.; Lau, K.T.; Diamond, D., “Autonomous Field-deployable Device for the Measurement of Phosphate in Natural Water”, SPIE Advanced Environmental, Chemical and Biological Sensing Technologies, Vol. 6755, September 2007 (SPIE Publications, TR2007-105)

McGuire, M.; Matusik, W.; Yerazunis, W., “Practical, Real-time Studio Matting using Dual Imagers”, Eurographics Symposium on Rendering (EGSR), June 2006 (EGSR 2006, TR2006-062)

Plus many many more…

This technical background comes through in his writings on wheel truing.  Instead of a traditional truing stand, for example, he instead recommends much more precise instruments:

2) Invest $40 or so in the machinist’s tool called a “Test Indicator”.
This is a nifty little jeweled instrument that measures position/motion
between two very nearby objects with great accuracy. Mine is a Fowler,
cost $37, has two jewels, and can repeatedly measure motion of .0005 inch
(yes, one half of one thousandth of an inch, or .0127 mm for our metric
friends). The hitch is that it has a max range of only .060 (+- .030 inch)

To use the test indicator- clamp the indicator’s mounting bar to a
convenient place on the bicycle (the brake post is a good place) and
flex it around till the tip bears against the rim and the needle
indicates approximately center-scale. You will have to move the
indicator between the radial and lateral truing steps (see below).

2A) There’s another kind of indicator called a “dial indicator” that
measures to within a few thousandths, over a distance of about one inch.
Dial indicators are a little more expensive, but you may want to
get one of those instead.

(Incidentally, my dad has been a machinist for his whole life, and recommended the same type of devices when I talked to him about helping me build my own truing stand)

If you are the mechanically minded type – which I’m guessing you would be if you are interested in truing your own wheels – I really do recommend reading his write up on the subject.  If nothing else it will give a perspective on the mechanics of the wheel and help you to understand what is happening when you turn those spoke nipples.

Bikes – and especially bike frame – are often referenced by a size, like 56cm or 27 inches.  For those “in the know” this is a good approximation to indicate if a particular bike will generally fit you.  While this may not be all that critical when you are in a bike shop and can actually throw a leg over the bike, this number can be important when you are looking on Craig’s list, for example.  So what does this number actually mean??

It actually is simply a measure of the length of the seat tube, from the center of the bottom bracket to the very top.  It is important to note that this is different from the saddle height.  While a particular person can actually ride frames of different sizes, generally the saddle height is constant for a given rider on any bikes that fits them.  However, when you hear the size of a bike mentioned, it is almost always this seat tube measurement that is being referred to.  The one place where will sometimes hear something different is when a bike is referred to as a “650.”  650’s are actually a reference to the size of the wheel – 650c – and not a particular frame tube.  Rather than confuse you with the completely incomprehensible world of bike tire dimensions, I’ll just refer those of you that care over to Sheldon Brown’s Tire Sizing explanation.

You may wonder why, if saddle height it what matters more, the seat tube length is so often mentioned as the size of a frame.  This is mostly due to the fact that it is truly a measurement of the frame, and not the overall fully equiped bike size.  It is also worth note that historically road bikes have usually had a frame geometry where the top tube is parallel to the ground, as in the Cannondale R300 pictured at right.

But many modern bikes don’t have a horizontal top tube.  Instead many manufactures are shipping frames that have a sloped top tube, like the Look pictured at left.  The attentive among you may immediately see the issue – if our top tube is sloping down doesn’t that make the overall frame size measure smaller than it will feel when we are on it?  Indeed it can – and how this is dealt with can vary from manufacturer to manufacturer.  By the book, however, the frame size should be exactly the seat tube length, regardless of the relative angle of the top tube.  While you may be expecting an imaginary line going from the top of the head tube and intersecting an imaginary line running through the seat tube, that’s generally not how bike frames are measured.

Another complication is that some manufactures don’t actually publish the exact measurements of their frames, but use more generalized size classifications like small, medium and large.  In these cases you can sometimes get your hands on a sizing chart from the manufacture that will give the size range in cm for a particular frame.

To illustrate how confusing frames sizes can sometimes bike, consider that both of the bikes pictured in this article are mine and basically fit me.  The Look, with its sloping top tube, is labeled as a “Small.”  It technically measures only 48cm.  The Cannondale, with its straight top tube, measures at 56cm.  If you look at the common “rule of thumb” sizing charts, someone like myself that is 5’7″ with a 30.5 inch inseam should expect to be comfortable on about a 53-54cm frame.  It is no coincidence that bikes labeled as small, medium or large are very commonly the models that do not have a straight, horizontal top tube.

And of course if you look at bikes like folding commuter bikes or mountain bikes, that don’t even have a front triangle (the triangle formed by the seat tube, down tube and top tube), then this whole frame measurement becomes completely irrelevant.

Nearly every bicycle tail light sold seems to come with hardware to mount it to the seat post, and observation would show that is in fact the most common location for people to put them.  However, if you put a cargo rack on the back of your bike, this location can become impractical for a number of reasons.  The rack itself may block visibility of the light from the rear of your bike.  And if not, any cargo you may actually want to carry on the rack surely will.

For many mounting the light to the back of the rack makes the most sense.  But how best to do that?  Some racks don’t have any special locations for mounting lights.  If they do, they may not be compatible with your light.  How can we sort this out?

When it comes to permanent rear rack light mounts – where the light gets bolted onto the rack – there are three common “standards” you are likely to run into, and a couple of US manufactures that are popular enough to almost be standards:

• Two horizontal holes, 50mm apart.  This is most common among European rack manufactures like Tubus
• Two horizontal holes, 80mm apart (Topeak has adapters in this size.  See below)
• Two holes, vertically oriented.  This is the most common bolt on options from American manufactures.
• Topeak racks often have mounting points built into the rack that are only compatible with Topeak lights.
• The slide-on / clip-on mount made popular by Planet Bike, among others

If you do not yet have a rack, light, or both and are reading this knowing that you will be purchasing soon, you’re in good shape.  Just being aware of the different mounting options will make you much more educated in your purchasing selection than most.

However, if you already have a rack and a light and you’re trying to figure out how to make them work together, you’re probably going to have to resort to either replacing the light, or finding an appropriate adapter.

As mentioned above, Topeak has an adapter that will allow you to affix an 80mm spaced light to a Topeak rack that has their integrated light mounting option.  It is interesting to note, however, that they do not seem to offer either a 50mm horizontal adapter, nor the vertical mount adapter.  If you’ve got a Topeak rack, getting  a Topeak light to go with it may just be your best bet.

Planet Bike, however, does sell a handy adapter that will allow you to mount pretty much any of their lights on a rack with a bolt on mount point.  This adapter bolts to the rack, and accepts the very common slide in clips.  Lights with these types are common not only on Planet Bike lights, but on may lights made by the other brands as well.  They are popular because they can be uncliped from the mount point, and clipped onto any piece of clothing (like a backpack or saddle bag) should you need to.  If you bought one of the smaller tail lights in the US market, there is a very strong chance it is compatible with this adapter.

Finally – what if your rack doesn’t have any light mount points?  This is unfortunately true for almost all of the low to mid priced, US made cargo racks.  Well – you’re not entirely out of luck.  Planet Bike also has a “universal” adapter that can perhaps help you out.

Knowledge of these different options can go a long way towards helping you make the proper tail light selection for your bike and rack.  While one would assume that a bike light will somehow just “work” for your bike, that is unfortunately not always the case.  And a light held in place with bolts will generally last you longer – and make you safer – than one hung in a haphazard way.

Chloe finally got to get her hands dirty as we stripped off the old running gear from the Fisher mountain bike for our singlespeed build project.  She’s biting at the bit to get her hands on the grinder and knock off the cantilever brake mount points.  I may just have to claim jurisdiction over that operation.

A couple of folks have already asked how I plan on mounting the brakes – especially the rear one.  In truth those details haven’t been totally worked out.  It may require a little custom-bracket making.  I’m giving serious consideration to actually moving the rear brake down to the chain stays instead of the seat stays.  We’ll see…

Just picked up this “gem” at a garage sale for $15:

I think we’re going to try and make this into a single speed (non-fixed gear) for my daughter.  She is itching to become “all mechanical” and really get her hands dirty working on a bike.  This particular frame seems like a good candidate because:

1) It is just slightly too big for her.  Perfect when you consider that she is growing like a weed, and I’d like the bike to fit her when the project is completed (not just when the project is started)

2) The frame has eyelets on the drop outs and seat stays – just in case she wants to mount anything on it I’d like to have the flexibility

3) Nice rugged steel frame

While some might find the couple of other items more of a detriment than a benefit, I like the fact that this frame as vertical dropouts, and cantilever brakes.  However, the mounts for the cantilevers are simple welded on mount points.  Therefore, considering the desire my daughter has to learn the actual hands-on mechanics, I see two opportunities.  One, we’ll have to work together through the gear selection / chain link removal to get the right combination of gear sizes and chain tension.  And two, we can grind off those cantilever mount points and switch to side-pull calipers (for mostly aesthetic reasons.)

So – my daughter’s first lesson?  Stripping down the frame, grinding off the “unnecessary” metal, sanding and painting!

Not too long ago, over on VeloReviews.com, I was casually discussing the possibility of swapping out my forks and quill stem for a threadless set.  My initial intent was to replace my aluminum forks with a carbon fiber set and change the stem type at the same time.  Well, turns out that conversion got expedited when I ripped my stem apart while riding home from work.  With something of a timeline looming over me (this bike is how I get to work) I opted to move forward with the a conversion of the quill stem by using an adapter to allow the use of a threadless stem.  The forks will remain the same.

In the top of this picture you can see the pieces of the original broken quill stem.  On the bottom, the more modern Bontrager stem pieces.  And finally, on the bottom right, you’ll see the adapter that will allow me to mount that Bontrager stem.

The adapter that I selected is made to be “universal.”  Here, you’ll see the sleeve that I’ve removed that allows this to fit a bigger headset.  However, I don’t need this so I can discard it.  You can also see a second sleeve on the top where the Bontrager will attach.  I will need this one.  I was apprehensive about having these spacers in there – afraid that slippage might result – but so far that hasn’t been an issue.

Bolting the stem on is nothing too special.  If you doing this off the bike like I am, just be sure you’ve got the angle of the stem facing the right way.  This particular adapter gives me exactly zero vertical adjustment here, but you can get some adjustment by changing how far you insert the assembly into the top of the forks.  However, notice the minimum insertion line on the side of the adapter in the photo above.  Make sure you’ve got the proper amount inserted into the forks.

With the pieces together, the whole assembly simply gets mounted as if it were a normal quill stem.  Slide it in to the appropriate depth and tighten the screw in the center of the shaft.

Because I changed stems, I’m also changing bars.  While not truly required, I’m moving to a more comfortable bar with a more standard 1 1/4 inch diameter.  My old bars were 1 inch.

Now – we just mount the controls, tape the bars and enjoy our finished product!

It was a normal commute home. I’d gotten off the train, was making my way home, warm night, light traffic. There were an unusually large number of folks riding their bikes too. It was sometime around 9:00 or so.

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That’s when I found myself at the intersection of W and 11th, heading towards Riverside Blvd.  I go through this intersection a lot, so I know the timing of the lights on this particular stretch of road.  If I hit the pedal really hard and sprint all the way to Broadway, I can just make it through the light at Broadway and Riverside Blvd.  I’m feeling kinda spry tonight – so I’m gonna shoot for it.  I’ve got a perfect track stand going – no need to be delayed by clipping into the pedals.  I’m totally gonna make this light.

As soon as the light turns green, I’m hard on the pedals.  One revolution – I’m in a fairly high gear, so sorta slow launch.  Push harder.  Two revolutions…  Three revolutions…  Bike is leaning hard to the left.  Wait… What?  I’m on the ground! I’m on the ground!  How the hell did that happen?

I’m in the middle of the intersection, laying on my elbow. A car slowly moves around me through the intersection, so my immediate thought is to get out of the road. I start to stand up and realize that I’ve still got the “sprint grip” (not to be confused with the “death grip”) on my bars. And that is when it hits me. I’m standing up with the bars in my hands, but the bike is still laying on the ground. The freaking bars are no longer attached to the stem.

Apparently I apply a fair amount of force to the bars when I attempt to sprint. I’d snapped the quill stem completely apart right at the weld point. Seriously something of a predicament. I had about 5 miles or so to go to get home. Walkable maybe, but not an easy walk. Especially difficult with a broken bike. Clearly I’ve got to call the SAG wagon for help. Or, as the rest of you may know her, my wife. Only problem is – no answer. Ummm… what do I do now?

D’uh! You take pictures and post them to twitter!

Well crap. Now how do I get home??? http://twitpic.com/2bpr49

Ok – then I try and call SAG… er, I mean my wife… again.

I get an answer this time, and she is already getting ready to come and get me when she asks, almost as an afterthought, “What happened?  Are you OK?”

“I kinda ripped my handle bars right off my bike.”  I reply, trying to make the situation sound all the more dramatic.

“Oh.”  That’s pretty much the full response.

Well, a few minutes later the car, complete with all three kids, arrives at the gas station just past the intersection where “the incident” took place.  The kids seem pretty excited about the fact that my handlebars are all the way down by the hub of the front wheel – hanging by the cables and swinging around aimlessly like a broken limb.  I manage to get the bike on the roof of the car and, after making a couple of half-hearted attempts to somehow contain the swinging handlebars, decide that we’re not going that far or fast so it’ll be just fine.

We get home and Melissa helps dress my elbow.  There was a small patch of abraded skin that was bleeding all over the place but not especially painful.  The fact that the whole thing happened after just a couple of pedal strokes was nothing short of amazing luck.  Things could have been a whole lot uglier if I’d crashed after I’d gotten up to speed.  Road rash is not something to look forward to.  However, the bar had been set pretty high in the “crashes won’t stop me” category, so I scrubbed out my elbow abrasion extra hard – just because.

On the ride home in the SAG wagon the Prius, I actually realized that just a couple of days earlier I’d heard a creak coming from the bars when I took off from a light.  At the time I didn’t give it much thought as it is not entirely uncommon for the bars or stem to creak as bolts slowly loosen up over time.  In retrospect, though, it was likely a harbinger of the eventual failure.  If only I’d recognized it as such.

One somewhat coincidental part of the whole thing is that I’d already been planning to get rid of that stem for different reasons.  Might have to expedite that project now.

Well, it looks like my Polar CS100 cycling computer will need to be replaced soon.  I’ve been using it for 2 years now (or is that 3?) on 3 different bikes.  I’ve used it to monitor my speed, cadence and heart rate.  While it has been a good unit for the most part, there are a couple of issues that have cropped up.

It first started when I moved the system from one bike to another.  While fully functional on one bike, I could never get the cadence readings to work after the transfer.  I tried several things – moving the sensor as close to the head unit as possible for example – but it would just never work again.  I can’t really explain why moving it would cause it to fail, but it did.  Then the heart rate functionality started to work only about 50% of the time.  I went through the usual gyrations of getting the sensor points wet where they contacted my skin and that helped for awhile.  However, it is now at a point where the heart rate monitor pretty much never works.  And the final straw – the speed sensor is failing more and more often.  I’ve watched my speed drop from 17 to 5 when I accelerate hard (clearly not right) and gone on rides I know are just over 30 miles, only to find my final ride distance at about 20 miles as reported by the computer.

I’m reluctant to try buying new sensors when the problem is very likely the head unit.  And buying a new head unit is, well, the whole thing.  Time to consider all of my options.

I definitely know that, in the interest of future usage, it makes sense to get something that is ANT+ compatible.  Most devices are moving in this direction, and there is a whole compliment of cadence, speed, heart rate and power sensors that could be hooked up to a reasonably capable head unit.  Given that the ANT+ protocol was actually originally developed for the medical industry, there is also the intriguing possibility that I may someday be able to use a cycling computer head unit to help manage my diabetes on the bike.

So what to get?  Well, I’m probably not going to spring for the power meter just yet.  But, I would be wise to consider which one I may get to ensure interoperability down the road.  And one really intriguing possibility is the MetriGear Vector.  At the time of this writing the Vector is not yet generally available, but is scheduled for release sometime this year.  The Vector is different from other sensors on the market in that the actual power measurements are taken at the pedals, with sensors embedded in both pedal spindles.  One of the most obvious benefits of this over, say, a single power meter integrated into the rear hub is that you can track the power output of both legs individually. It also allows for increased flexibility in application.  A power meter in the rear hub is a difficult thing to move between wheels (lacing spokes is time consuming, and still appears to be something like voodoo to me.)  It is not uncommon to have different wheelsets for different applications – training wheels, racing wheels, wheels specific for rides with a lot of climbing.  Since swapping out hubs is not practical, that means a new power meter for each new wheel.  Not a cheap proposition.

Pedals, on the other hand, are quick and easy to swap.  Initial reports seemed to indicate that MultiGear would initially roll out with support for Speedplay Zero only.  However, information posted to their website seems to hint that this relationship may not be entirely set in stone:

On a separate yet significant note, you may notice that we are now showing Vector integrated into spindles (and no pedal bodies) on our web site. Vector will still include a set of pedals, but we are currently re-evaluating the pedal platform Vector will use to make its market entry. We’re in the process of evaluating several options, and will continue to do so in parallel with our development and test phases. We understand that there will be a lot of questions on this critical decision, so we will be more specific as soon as we have something definitive to share.

That still leaves the question of exactly which head unit to get.  To be honest, I still have no idea.

Garmin seems to be to cycling computers what QTip is to cotton swabs these days.  But I don’t want to just jump on that bandwagon too quickly.  For one thing, I’m quite happy using Google Maps and CardioTrainer on my Droid smartphone for my mapping and tracking needs, so all of the GIS functionality offered by the Garmin units are not necessarily worth the added cost at this point.  Cateye and CycleOps are other names that come up alot, but to be honest the options are pretty numerous.

So – what are your thoughts out there?  For those of you using an ANT+ capable cycling computer, what are you using?  Why did you chose it?

This one killed me at first.  I broke the retaining clip that holds the pawls of my Fulcrum Racing 7 freehub.  It would sometimes take me a full revolution of more to get the pawls to extend enough via centrifugal force to engage and move me forward.

I bounced from local bike shop to bike shop trying to find a replacement part that wouldn’t take one to two weeks to arrive.  After identifying the two shops of a dozen or so in my area that actually sold Fulcrum, only one had a clip that was “only for Fulcrum Racing 1, 2 or 3” according to the guy in the shop.  Things didn’t look promising for me.

But then I decided to go poke around the Fulcrum website.  I was very pleasantly surprised to find that they had complete parts lists there, along with the catalogs and user manuals (user manuals for wheelsets??)

Well, much to my surprise – and quite despite what the one guy that had a clip in stock told me – all of the wheelsets had the same part number.  There it was – good ol’ 5-R1-015.  Didn’t matter what wheel.  Didn’t matter if the hub was Campy or SRAM/Shimano.  It was the same part number.  Happy days!

Unfortunately when I found this out it was too late to drive back to the shop that had the clip.  Besides, it was about 30 miles or so away and I didn’t really want to make the trip.

On the advice of others, I tried a shop in Sacramento that I’d never been to before – Ikon Cycles (also on Facebook).  The guy was quite helpful.  He also didn’t have on in stick (D’oh!) but… he said he would call his supplier and call me back.  Sure enough, 30 minutes later he called me back.  His news – he’d have one for me the very next day.  Sure as hell beats the 7-14 days the other shops were talking about.

I understand that shops can have difficulties getting specific parts from suppliers.  But the guy at Ikon was super helpful and seemed to know what he was talking about.  And he didn’t even blink about taking the time to order a part that retailed for less than 5 dollars.  Awesome customer service.  I definitely know where I’ll be calling first for parts from now on.

For any others interested, I’ve included a copy of the  Fulcrum Wheels 2009 Spare Parts Catalog – just in case.

Like most things high performance, carbon fiber has its benefits and its drawbacks.  Benefits, of course, include things like increased strength to weight ratio, stiffness and vibration dampening.  Drawbacks include the fact that abrupt strikes, such as the forces that occur during crashes, can result in internal cracks to the structure. These cracks can cause components to ultimately fail.  Unlike steel or even aluminum, these cracks can be non-obvious, and are not repairable.

Therefore it is very important that your carbon fiber parts be inspected after crashes.  Of course you should always have this done by a qualified professional, as a failure of a frame, fork, bars, or other component while riding can result in serious injury or death.

I recently had such an experience (documented in high-definition point-of-view glory) that resulted in my FSA CarbonPro Compact bars striking the ground rather abruptly.  I definitely wanted to give the bars a detailed inspection.  The visible damage was fairly minor – abrasions on the tips of both brake levers, and some ripped tape.  However, the very thought of the possibility of the bars failing while I was riding definitely warranted the cost of a new roll of bar tape and an hour of my time.

So of course this whole process began by stripping off the existing bar tape.  In this case – because I wanted to inspect the bars both visually and by touch, I actually took the time to clean off all of the glue left over on the bars.  Always be careful of any solvents around carbon fiber parts – keeping in mind that the entire part is basically a petro-chemical mold.  I prefer either rubbing alcohol or a citrus-based cleaner for heavy-duty carbon degunking like this.

Interesting side note – if you look closely at the photo of the stripped bar, you’ll see something funny.  Notice how that trademark “carbon fiber weave” look stops about where the bar tape started?  Now why would that be?  Well, the dirty little secret of carbon fiber bike parts is that in almost all case, that weave look is completely cosmetic only.  Folks have become so used to carbon fiber parts looking like that they often don’t believe it is even carbon fiber unless they see it.  The truth is the actual structures that give carbon fiber its strength in bike applications are pretty much never this cross over weave.  That’s why it stops where the bar tape starts – you can’t see it under the bar tape, so there is no real reason to continue it down there.  That carbon fiber weave has no more purpose than the painted on logos elsewhere on the bars!

So now to the actual inspection.  I was looking initially for any visible lines in the material – the part should be consistently smooth and glossy over the entire bar.  I actually did find one small line in the the left hand drop and employed the “thumbnail” test.  The idea here is that if you drag one of your finger nails across the mark, you should not feel anything if it is just a scratch.  However, if you can feel your nail “catch,” you’re probably dealing with something much more significant.  In my case, I can’t feel it at all – so it is a pretty safe bet it is just a scratch, perhaps something that happened during the assembly of the bike.  To check even further, I put most of my weight down in the drops.  If this were an actual crack, that pressure would cause it to widen and be even more likely to catch my nail.  Still no catch, so I move on.

The next technique I used involved a very specialized tool – a quarter.  Carbon fiber tubing will make a distinctive tink sound when you bounce a quarter on it.  However, internal cracks will actually interrupt the continuity of the carbon fibers and result in more of a dead thud type sound.  My bars produced a beautiful tink from one end to the other.  Literally music to my ears.  Crashing is bad enough – having to drop a few hundred duckets to replace your bars is just pouring salt into the road rash.

There are a couple of benefits from being forced through this exercise.  First off, this is a perfect time to get some lube on the cables coming out of the controls.  Secondly, you may have noticed that the bar tape that shipped with my bike didn’t cover the top of the bars at all.  Presumably this was to show off the wonderful “CarbonPro” logos that were painted there.  However, it meant that casual riding on the tops meant my hands were right on the slippery, hard bare carbon.  Well, I’m not nearly as motivated to make sure the logo is visible as the company was, so I’m free to extend the wrap all the way up to a more normal length.  This was always something I wanted to do, but I didn’t feel justified in ripping off the perfectly good bar tape just to get it up higher.  Now I’ve got my excuse.