Saturday, December 12, 2009

Rivet nut replacement

When I attached my water bottle cage to the seat tube of my new bike I failed to notice I was using aluminum bolts. That bit of carelessness resulted in breaking off the first of the 5mm bolts I tightened.

Normally this a simple fix using a Craftsman Drill Out Micro Power Extractor to remove the remains of the bolt, but it was not going to be that easy. When attempting to extract the bolt the rivet nut started spinning in the frame. The combination of spinning rivet nut with a broken bolt stuck in it left me no choice but removal.

After drilling out and removing the rivet nut's remains from the frame, I purchased a Marson zinc plated 5 mm Riv-nut from Bikeman ( ) for $2.99 USD. Actually I bought two just in case I spoiled one on my first installation attempt. This turned out to be a good investment.

I didn't want to purchase a rivet nut tool, so after doing some searching I found instructions on the Park Tool website ( ) on tightening up water bottle fittings. While the instructions and make-shift tool used are for just tightening a loose rivet nut, I decided to take the chance they would also work for installing a new one.

My makeshift tool consisted of an adjustable spanner as the spacer, a cheap steel front skewer, and spare Campy front hub. The picture to the right shows the setup with Riv-nut in place. My first attempt to install the Riv-nut yielded a couple of problems. The first is the thickness of the adjustable spanner's jaws are tapered. This, in effect, creates a wedge between the skewer and the axle nut resulting the bending of the skewer when tightened. The second problem is the axle ends are not flat but beveled distorting the Riv-net's face as pressure is applied . The result was bad enough that I decided to remove the Riv-nut an start over.

On my second attempt pictured on the right, I corrected the shortcomings of my makeshift tool by substituting an open end wrench with uniform thickness that would still be me a good leverage. I also installed a washer on the skewer between the axle end and Riv-nut to provide a large flat surface.

Admittedly it took a fair amount of effort using this setup to install the Riv-nut since the skewer doesn't provide a lot of leverage. With each close of the skewer's lever I had to screw the skewer a little bit further into the Riv-nut and repeat. After several iterations of this, I was able to compress the Riv-nut sufficiently to secure it into the frame.

After thoughts... I think the technique I used is probably not a good solution for installing a new rivet nut. The hub or even just the axle from it is a bit awkward to use and requires a lot of finger strength to set the rivet nut. Probably a better low-cost alternative to a proper rivet nut tool would be a strong steel 5 mm x 20 mm bolt, a mating steel nut, and some washers. The idea would be the nut, bolt and washer assembly would be screwed into the rivet nut and with the bolt held in place while the nut is backed off thereby compressing the rivet nut. This would give more control and require much less effort.

Lastly, while writing this entry I found a source for a very basic rivet nut tool for under $30 USD from ( ). The tool itself looks simple and easy to operate within the confines of a bike frame so I am considering purchasing one.

Tuesday, November 17, 2009

iPhone, GPS, and battery capacity

One of things that attracted me to the iPhone 3Gs the GPS apps available to plan and track my bike rides. It wasn't too hard to decide on the MotionX GPS app that is both very capable app and reasonably priced at just $2.99.

I suspected that I was going to need an external battery and my first ride with the GPS confirmed it. After only a few hours with the GPS app running it consumed enough of the battery's charge that I had to stop it so I would have a phone if needed during the ride.

When I got back home I started searching for a high capacity rechargeable external battery. The ones I found were disappointing either from the standpoint of battery capacity or how they attached to the iPhone.

Some were units that plugged into the bottom of the phone extending its overall length and putting what think is unacceptable stress on the iPhone's connnector. Others connected to the iPhone using a cable making them clumsy to use with it attached.
I decided what I needed was something that did not plug into the iPhone, but something the iPhone plugged into. The ideal was the battery should be basically a case housing the iPhone, but not interfering with normal operation.

What I found was the FastMac TruePower iV iPhone Battery Charger. It has a whopping 3100mAh battery compared to the iPhone 3Gs battery of only 1150 mAH. That is 2.7x more battery capacity! The extra bonus is a "flash" which is just a LED light activated by an external switch is handy when you need a flashlight, but not much good for pictures. It also has a USB connector to allow the TruePower iV to charge devices such as Bluetooth headsets which I haven't used yet.

A desktop test showed the additional battery capacity allowed for over 8 hours of full use of the MotionX GPS app with battery capacity to spare. This meets my need to have GPS for an long day's ride without compromise.

The TruePower iV is near perfect, but there are a few misses. At about $100 USD, its expensive. It doesn't provide the same protection as the typical case. It doesn't hold the iPhone as tightly as I would like leaving the possibility of it becoming accidentally unplugged especially when in my backpack.

For a full description of the FastMac's TruePower iV go to

Disclosure -
My only relationship with MotionX, Apple, AT&T, and FastMac is that of paying customer.

Monday, September 21, 2009

Break a rear derailleur cable on the road?

What do you do when your rear derailleur cable breaks while on the road?

1) Praise yourself for having the foresight to have a spare cable and allen wrench in your bag?
2) Struggle on the best you can?
3) Jam a rock or stick into the dérailleur so you can ride the cassette's middle cog?

We were riding the Illinois I&M Canal trail when my buddy's rear dérailleur cable broke. There we were on a course gravel trail without much of anything in sight, no replacement cable, and rain threatening.

Without a replacement cable and on the last 20 miles of a 75 mile ride, we decided on the old-school choice number 3 from the above list.

We couldn't find a stick that would set the deraillieur in the correct position, but we managed to find a rock that did the job. The tape taken from a first aid kit wasn't really needed, but added as a precaution

Afterward I was able to remove the rock with the help of some pliers, but no damage and installed the new cable.

Friday, September 11, 2009

Determining Saddle Width

What is the minimum saddle width necessary to ensure a reasonable amount of comfort on those long rides? Conversely, is the saddle you ride now too wide?

Recently a friend expressed displeasure with his current saddle and concern about the potential cost of going through a number of saddles before he found something good or at least sucked a lot less. He currently rides a Terry Fly Cromoly Gel which has a width of about 140mm. I suspect the saddle is way too narrow for him, but other than trial and error how can I prove it?

Even though two Specialized BF saddles I have tried in the past didn't suit me, I do appreciate their efforts to properly size saddles to riders with their trademark Body Geometry Saddle Fit System and multiple saddle widths. As with their system that measures "sit-bone" width I needed to come up with a cheap and easy DIY method of doing the same while the rider is on his or her bike.

After giving it considerable though, forgetting about it for a few months, and then finally getting sufficiently bored today to take action, I used the following method:
  1. Cut a simple saddle form out of 1/2 or 3/4 plywood or MDF using a jigsaw
  2. Sacrifice an old saddle and attach its bare undercarriage to the wooden saddle form with flat head wood screws
  3. Place the rider's bike on a trainer
  4. Loosely mount the makeshift saddle on the rider's bike
  5. Cover the top of the saddle form with modeling clay
  6. Using a 1-inch dia or larger. 3ft hardwood dowel roll the clay to a smooth consistent 10mm thickness
  7. Trim off the excess clay hanging over the edges of the saddle form with a knife
  8. Cover the top of the saddle with a sheet of clear plastic wrap.
  9. Make any necessary saddle and seat post adjustments for setback, angle, seat height, and proper bolt torque.
  10. Place the rider on the bike in his or her normal riding position and have him/her pedal for a few minutes
  11. Have the rider get off the bike and then remove the saddle
  12. Remove the clear plastic wrap from the saddle and carefully highlight the ridges and indentations in the clay with a marking pen
  13. With a metric ruler take the necessary measurements to determine "sit bone" spacing

The Saddle
(Click on this picture to enlarge)

The Measurements (Click on the picture to enlarge)

The results show my "sit bones" spacing at 110mm when measured center-to-center. Also measuring from the outer edge of the right "sit-bone" indentation to the outer edge of the left is about 155mm. I am saying "about 155mm" because I am estimated this measurement because the saddle form was not quite wide enough.

These measurements give me some confidence my method works since I know from many years and many saddles worth of trial and error that a saddle width of about 155mm is good for me. Not suprisingly this also explains why my favorite saddle remains the Brooks Team Pro given that amongst its several outstanding attributes is its 160mm width, albeit its usable width is closer to 150mm. However, the measurements put this saddle in the category of being just barely wide enough and suggests I should consider a bit wider model like the Brooks B17 Special with a width of 170mm.

While correct saddle width is just one factor in finding a saddle that meets a rider's needs, it is a very important one. With this metric riders shopping for a new saddle can quickly eliminate saddles that are unnecessarily wide or too narrow from the list of possibilities.

This weekend I will be providing my DIY saddle fitting system to my friend mentioned at the start of this post to him in his selection of a new saddle. My guess is that will show a wider saddle is warranted which will also significantly reduce the list of choices.

Sunday, July 5, 2009

Bike Camera Project - Update

Here's a quick recap of the initial post from April 26: I found the Pedco UltraClamp Camera Mount ($24, ) a good choice and a test ride with a small camera showed that vibration did not create a significant image quality problem even on a rough road.

For the 2009 Bicycle Tour of Colorado I decided on the Pentax W60 camera because of its size, picture quality, capacity, and the very important factor of being waterproof. A test prior to the trip showed the camera to have a few flaws. The first is the battery vibrates inside the camera body on rough roads and the second is a loud auto-focus motor. Both these flaws contribute to considerable noise on the audio tracks of videos during pre-trip tests.

Fortunately, I was able to work around these two flaws by placing cardboard strips around the battery to give a tighter fit inside the camera and by disabling the auto focus then taking videos. However, I still found the W60 much more susceptible to wind noise than the low-cost Casio Exilim 7.2 megapixel camera used in my initial tests. I was not able to workaround this problem in time for the BTC. I also gave up on the solar cell battery charging solution because of concerns of the cost, possible fragility and size of the panels, and number of daylight hours needed to obtain a fully charged battery.

From an ease of use and picture quality standpoint I found the camera met my needs, especially when taking photos. Also the camera is definitely waterproof since I used it in the rain, fog, and early morning damp.

Because I didn't have a good battery recharging strategy, I didn't do much video, but I did manage to capture some of the decent from Independence Pass on the last day of the ride. The raw video is HD quality, but with a useless audio track for reasons mentioned above.

Vibration from rough stretches of road, the camera tried to unscrew itself from the mount and you will notice in the video that I reached down and straighten the camera on its mount several times. I haven't address this problem yet, but I suspect it could be fixed by making the mounting surface rough by attaching a few strips of fine sandpaper to its surface to grab the camera better.

Unfortunately upload process considerably reduces the quality of video due to compression. Bike speed was in the 20-40 mph range for most of the video.

Additional thoughts:

If I had it to do over, I would probably go with a generator hub so I could charge my phone, netbook, camera on the road. Reduction of wind noise is a must to create quality video. This might be achieved with some foam over opening for the camera's microphone and/or some type of wind-block around it. There is also the possibility of switching to a noise reduction microphone/headset to reduce wind noise, but at the cost of acquiring a waterproof camera that supports this option.

Saturday, May 9, 2009

Always inspect your bike - example of a cracked rim

Here's a good example that when overhauling or just cleaning a bike you need to also perform a careful inspection for damage.

I was working on a friend's bike and when I got to cleaning the rear wheel I got a surprise. I noticed cracks around the eyelets of the rim on his rear wheel. The rim is a 36 spoke Mavic Open Pro so it should be plenty strong, but the rider is a Clydesdale and the rim are several years old.

This picture shows the worse of cracks. The cracks are so bad I declined to attempt to true the wheel and strongly recommended the rim or entire wheel be replaced. Being a Clydesdale myself I recommended what I normally ride which are Velocity Deep V rims with 36 spokes in the rear and 32 or 36 spokes in the front. I have found this combination to be near bullet proof.

Sunday, April 26, 2009

Bike Camera Project

During this year's Bicycle Tour of Colorado I want to capture some of the spectacular scenery and downhill runs on video.

I considered both helmet and bike mounted cameras. Both have their advantages. The helmet camera is obviously has the advantage of inherent vibration dampening and tracking the riders point of view. However the helmet cams I can afford lack the flexibility of also serving as a high quality still camera and take only a limited amount of SD memory.

On the other hand there are plenty of 8-plus megapixel relatively inexpensive cameras out there that can also do fairly good video, however I don't think I want them hanging off my helmet.

My worry about the bicycle mounted camera is first finding a secure method of mounting the camera to the bike that won't interfere with normal operation and can be removed easily when not in use. There are several DIY bicycle camera mounts possible but I was unimpressed with all of them. Luckily I found one off the shelf at my local REI store that is near perfect. The Pedco UltraClamp Camera Mount ($24, ) attaches to the stem of my bike with just a twist of its set-screw and fits as if it were made specifically for this purpose. The mount also has three points of adjustment that make alignment of the camera simple and quick. This is problem solved, it was on to the second concern.

A bike mounted camera will need to cope with some road vibration that may cause blurred video and possibly even damage to the camera itself. To address the blurred video concern I decided on a test using the Pedco UltraClamp Camera Mount and cheap Casio Exilim 7.2 megapixel camera I already own with a 512 SD card doing 640 x 480 30 fps video. I selected a rough stretch of road that is fast with few stops and some small hills as the perfect test track for vibration. The following video starts on a fairly smooth bit of road for reference prior to turning right on to the test road.

Viewing the video you can see that even at 20+ mph on the test road vibration doesn't impact the image quality significantly . A reminder here the video is desgraded in conversion process of uploading to this blog. Now the the 512MB of SD memory provided under 7 minutes of video recording, which is another concern I will discuss later. After about 20 miles on the bike the camera mount remained secure, but there was a minor problem. The camera wanted to twist counter-clockwise on the camera mount in response to road vibration. Basically, it was trying to unscrew itself. I think I can address this either by brute force tighten of the mount screw or perhaps using something like Locktite Blue on the threads. If not then I will need to place a vertical pin on the mount pad to physically stop the camera from turning.

With video quality assured then it was a matter of selecting a camera rugged enough to handle the vibration and unpredictable weather of Colorado. After looking at many-many cameras I decided on the Pentax W60 which is small, rugged, waterproof, and feature packed. The best news is that at the same video resolution and frame rate I used in the initial test, I will have over 6 hours of continuous video with a 32GB SDHC card! While I am not certain how long the camera battery will last, this can be fixed by purchasing an extra battery, if needed. I have the Pentax W60 on order and I will provide a project update after I take it for a test run.

There are a couple of remaining issues that I need to address. When I did the BTC for the first time I decided to camp-out. This worked out fine, except that access to A/C outlets was just about non-existent, so charging devices like cell phones and cameras was impossible. The other issue is how to off the 32 GB SDHC card over the 7 day trip.

The good news is that I may have the charging problem solved with use of a light weight folding solar array that provides 12DC at with sufficient current to charge the Pentax W60's battery(s). I will provide a project update after doing more research. The storage problem is an issue since my Netbook only has 16 GB of solid state hard disk in it, so I clearly need some other mass storage device. Of course I could fix that problem by brute force with 7 32 GB memory cards, but at about $90/card that is an expensive solution. My guess is that I am going to use a small USB powered external hard drive in conjunction with my netbook. More to follow!

Wednesday, April 8, 2009

Overhaul of a Lemond Chambery

A coworker asked me to overhaul his Lemond Chambery last weekend. ( Picture is of the finished bike)

Some searching on the web indicates this bike to be from the late 1990's making it about 12 years old or so.

First inspection showed the bike to be dirty with tattered bar tape and tires rotted by age. Additionally, the shifters were "broken". The coworker provided me with replacement Continental Ultra Gator Skin Rigid Bead tires and a pair of used brake/shift levers he got off of ebay. He left it to my discretion as to whatever else needed replacement.

My first effort was to see if I could restore shift function to the levers and avoid using the lesser quality replacements. The problem was typical where the triggers fail to release the shifter. To address the problem I washed out the brake/shifter assemblies with about half a can of dry film silicone spray lubricant. The result was a brown dirty pool of lube on my shop floor and two working shifters.

Knowing that I was going to replace the brake and shift cables regardless of their appearance, I cut them off and put the loose cable housing aside for re-use since it was in good shape. Once the bike is completely assembled, clean, and otherwise ready to go, I would install Aztec Teflon brake and shift cables. I like the Aztec cables for their low cost, low maintenance, durability, and smooth operation.

I removed the tires from both wheels, removed the rear wheel's cassette, and did a detailed inspection after a very thorough cleaning . I found the wheels were fairly close to being radially and laterally true. There were no cracks, dents, or signs of excessive wear on the rims. The nipples and stainless steel spokes were in very good shape. However, I did find the rim tape on both wheels had been improperly installed leaving gaps exposing the tubes to the spoke ferrules, so I replaced it.

Next, I inspected the hubs' races, cones, bearings, and condition of the old lube. The lube was clean and the parts showed very little wear! With everything looking good, I cleaned the hubs, lubed, and assembled them. Next, I trued the wheels to about 1/2 mm tolerance and less than += 10% variation in spoke tension.

Given the age of the old tires and decided to replace the tubes, as well. One of the things I like to do is dust the inside of the tire casing with talc or baby powder. I think this makes the installation a bit better because the tube can move freely inside the tire during installation and initial inflation. The Continental Ultra Gator Skin has an arrow on their side wall denoting direction of rotation that is easy to miss and people often do. I don't know if it makes much or any difference, but I made sure to mount the tires so they would rotation in the correct direction.

Lastly for the wheels I did something that is too often overlooked. I carefully cleaned, lubed, and inspected both skewers. Since these things hold the wheels on the bike, I think it is time well spent.

The chain was pretty gummed up so I decided junk it for a new SRAM PC850 8-Speed Chain. I really like the SRAM chains for their durability and smooth shifting. The SRAM Powerlink included with this chain will also make future maintenance a bit easier for the owner. With my inspection of the rear derailleur I found the bottom pulley to have a bad sealed bearing. After removing and scrubbing the rear derailleur in solvent I installed the replacement pulleys, lubed the derailleur's pivot points, and reinstalled it on the hanger.

There was a lot of dirt around the bottom bracket and on the chain wheels so I decided to pull the crank arms off to make the cleaning easier. This also allowed me to remove the BB cartridge, inspect it, and inspect the surrounding area. After scrubbing the crank arms, bottom bracket cups, and chainrings in solvent I found them to be in good shape with little wear. The BB cartridge was also in good shape moving freely and smoothly. After cleaning/lubing front derailleur, bottom bracket threads, and cleaning the surrounding area I re-assembled the crank. The cleaning really made the replacement red alloy chainring bolts and dust caps visible.

The pedals had some serious dirt and a bit of rust on them that was probably interfering with the insertion of the cleats. It took some solvent and scrubbed the pedals with a stiff brush to remove the dirt and sprayed them with dry lube. The pedals moved freely and easily on their axles so I skipped redoing these bearings. Overall the pedal came out OK except they were pretty beat up in appearance.

The bike had some butt-ugly Profile Design bolt-on aerobars that would make wrapping the handlebars nearly impossible so I removed them. (Note: they were so ugly I didn't re-install them until after I took the picture above). The fork moved smoothly and freely, but I decide to remove the stem and fork for a couple of reasons. I wanted to inspect the metal steering tube for any damage from possible prior over-tightening of the quill stem bolt and inspect the point where it meets the carbon fiber fork crown. The good news was that after a thorough cleaning the fork and headset looked good. I reinstalled them and made a final adjustment without trouble.

I decided to take advantage of the handlebars being free from the bike and wrap them at this point. With some difficultly I removed the old tape and underlying adhesive. I was a little surprise to see the beautiful Cinelli handle bars had been deeply scored by the heavy handed clumsy prior use of a box or razor knife to remove handlebar tape. Given the bars are heavy aluminum construction and the scoring being at the end of the bars I decided replacement was not warranted. I also removed and replaced the vinyl tape holding the shift cables in place on the bars because it was badly stretched.

When I received the bike it had red/black cork handlebar tape no doubt to match the red anodized replacement alloy chainring bolts, dust caps, derailleur pulleys, and alloy nipples of the front wheel. However, I decided on a black and yellow cork tape with the idea this fit best with the gold lettering on the down tube and fork. Even with the yellow in the tape being slightly lighter in color than the lettering, I still think it was a good choice. With the bars wrapped I reinstalled bar and stem. By dumb luck I had some yellow tie wraps that I used to mount the wireless cycle computer's sensor on the fork which I thought was a nice touch.

Until now I was cleaning areas of the frame as I went, but it was now time for an overall cleaning and polishing of the frame. But after starting, I noticed the once clear chain stay protector had yellowed and looked pretty bad on the refrigerator-white frame. I decided to replace it with a Lizard Skins Carbon Leather Chainstay Protector because I thought is looked kind of cool and offered better protection than the original. After installing it, I finished cleaning the frame and fork with Finish Line Super Bike Wash. This took some elbow grease, lots of shop towels, and patience. I found the white finish was good looking, but showed every smudge and small scratches in the finish captured dirt very effectively. Once the frame was finally clean as I could get it, I finished it with Pedro's Bike Lust polish.

After giving the rear cassette a final scrub and re-installing it, I put the rear wheel back on the bike and made the initial adjustments to the derailleurs. Next I installed the previously mentioned Aztec shift cables, cut them to length, and put on the crimps. Here's something often overlooked when replacing cables. Make sure you turn the adjustment barrels to their minimum position before installing the new cables! This ensures the adjustment barrels will be able to accommodate both fine adjustments immediately after the cable installation and component wear or cable stretch over time.

With the shift cables installed I did some fine adjustments on both the front and rear derailleur to make sure nothing rubbed and both indexed through the gears without trouble. Even with a new chain I like to start out with a generous application of White Lighting chain lube. With the drive train assembled and adjusted I careful lubed each link in the chain.

Next I put the front wheel on and checked the alignment of both front and rear brake pads. Surprisingly the brake pads looked good and were perfectly aligned so all I had to do is install the new brake cables after screwing down the adjustment barrels, cut them to length and put on the crimps. Not previously mentioned was that I had cleaned, lubed, and inspected the brakes themselves when I did the final cleaning of the frame.

Since my goal was to make the bike completely road-ready, I decided to go the extra mile and replace the cycling computers batteries, and add a small frame pump under the down tube water bottle cage. I also equipped the saddle bag with patches, tire irons, spare tube, and spare sensor battery for the wireless cycling computer.

After taking the picture above, I resigned myself to putting the aero bars back on which made me a little sad since it screwed with the good looks of the bike and clean cable runs. With the aero bars on I mounted the cycling computer to them and calibrated it to the new tires.

Here's another thing that is often overlooked by folks working on bikes. I went over the bike one last time checking adjustments, bolt tightness, alignments. This check ended with a quick test ride to verify shifting and braking were 100% good.

The bottom line for the overhaul was $147 in parts (not including tires, cleaning supplies, and lubricant) and about 6 hours of labor on the bike over 3 days. My co-worker was very pleased with the results and accessories I selected.

Thursday, March 26, 2009

Road-side pardons for motorists killing and injuring cyclists

When I started this blog I decided to avoid ranting about bad drivers. So far I have resisted this rich source of material, but there is a related issue that has me concerned and curious enough to speculate on an underlying cause.

There are numerous accounts of motorists escaping responsibility for their violating traffic laws which result in injuries and deaths of cyclists. Googling "police refuse cite motorist bicycle" will provide the needed examples across the U.S. After reading a few dozen accounts, the general scenario seems to be:

  1. A motorist either unknowingly or deliberately violates the law

  2. The violation results in the injury or death of a cyclist

  3. The responding police officer makes an on-scene decision to not cite the motorist

  4. Appeals for justice either fail inexplicably or due to lack of evidence.

I think it is safe to assume that not all of these sources are unbiased and accurately representing all the facts. I have first hand knowledge of police officers taking great exception to motorists' bad behavior around cyclists and their concern for cyclists' safety even when those cyclists break the rules of the road. Additionally, it can be remarkably unfair when critics use the benefit of 20/20 hindsight to question decisions made by police officers based on facts available at the time.

All that said, the number of the reports and their similarity have me speculating on what might be motivating a small number of well-trained good intentioned police officers to effectively look the other way then motorists' illegal behaviors result in the injuries and deaths of cyclists.

Could it be that some police officers are blaming cyclists for their own injuries and deaths? I just don't see an alternative explanation that makes sense to me. Their thinking might very well be that persons choosing a bicycle over a car are knowingly placing themselves in such a hazardous situation that motorist are reduced to unwitting participants in accidents involving cyclists.

So why are roads actually and/or perceived as hazardous to cyclists? There are the obvious situations like narrow two lane roads and bridges heavily traveled by cars and trucks at high speeds. However, I avoid roads that put me at high risk and I still manage to have close-calls with motorists just about every time I ride my bike. When I say "close call" its means one or a combination of the following:

  • I am forced to take evasive action to avoid being struck by a motor vehicle

  • Motor vehicles when passing me risk head-on collision with oncoming traffic

  • Motor vehicles passing well within 3 feet of me; especially large vehicles at high speed

  • Motorists using aggressive driving or other bad behaviors to force a response from me

This frequent bad behavior of motorists leads me to believe that states are licensing a number of motorists that are lacking the minimum skills, knowledge, judgment, attentiveness, and temperament to safely drive multi-ton high-speed vehicles in mixed traffic. Most concerning is this has serious ramifications for the effectiveness of new and proposed laws intended to improve the safety of cyclists sharing the roads with motor vehicles.

The state by allowing ignorant, inattentive, incompetent, and ill-tempered persons to obtain and keep their licenses sets law enforcement's low expectations of driver performance in mixed traffic. In short this is, in my opinion, the root-cause of the perception amongst some in law enforcement that holding motorist to the higher standard of behavior required to keep cyclists safe is unfair to motorists.

The new laws passed like the 3 ft rule and others being proposed to protect cyclist are overdue, but to be effective people licensed to drive must be willing and able to following them. Until then the defense of "too ignorant or too ill-tempered to drive safely amongst cyclists" will continue to be a source of road-side pardons for motorists injuring and killing cyclists.

Saturday, March 21, 2009

Saddle comfort - A 100 year old solution with a twist

I have bikes made of titanium, exotic aluminum alloys, carbon fiber, and stainless steel, but I have put old-school leather saddles on them. Why?

The saddle on my first serious bike (Windsor Pro Columbus Frame with Campy Nuevo Record & Cinelli components) was a used Brooks Pro. At the time I didn't know better so I didn't realize how lucky I was. I found out with my second bike (Ron Cooper Reynolds 531 Frame and most of the components from the Windsor Pro) when I bought a shiny new Brooks Pro Saddle for it. It was hell breaking the saddle in, but eventually worth it.

Over the years for the sake of weight and fashion, I gave up my Brooks saddles for plastic ones with either foam and/or gel padding covered by either plastic or leather. A few of them have been acceptable for longer rides and one qualifies as a device for slow torture.

The Terry Men's Liberator Gel was certainly one of the best in the plastic and paddling group. My opinion is that is deserves the good reviews.
An honorable mention needs to go to a very inexpensive Serfas Deep Groove Saddle that I had on a road bike for several years. It was wide enough, with a smooth cover, nice shape, narrow horn, large cut out, and probably too much foam padding.

The Specialized Avatar Gel Saddle (155mm width) is hands-down the absolutely worst saddle I have every experienced. I know they put good science into the design and the saddle has received good reviews, but, after riding it for just a few hours, it would create silver dollar size sore spots where my sit bones contacted the saddle. I am not talking about a little bit of discomfort, but bad enough to keep me off my bike the next day. Ironically the less expensive model, the Specialized BG2 Sport Saddle (150mm width), I found more comfortable which also provided a clue as to why the Avatar was just so bad for me.

Third on my most comfortable saddles list is a stock Brooks Pro (160mm width) now on my hardtail mountain bike. It was tough breaking it in, but with frequent applications of Brooks Proofide Leather Saddle Conditioner and lots of miles it is now a pleasure to ride. The more upright riding position I believe keeps the pressure off things that shouldn't have pressure on them, so no cut out or slot is not a problem.

Taking second place on my all time most comfortable saddles list is the MCM Selle An-Atomica Titanico LD . It is similar to a Brooks saddle, but with a slot or cut out in the leather that is nothing short of a brilliant bit of elegant design. This enhancement allows the leather to more easily flex with the rider's movements which signficantly improves comfort. However the saddle gets a few points off because the rails are not as robust as I would like and the craftsmanship is not up to par with Brooks. I also found the saddle tended to flare out and rub my thighs until I drilled and laced it. This actually worked out since the saddle with the addition of the old-school lacing looks great on my fixie. One other thing I have to mention is that MCM Selle An-Atomica has great customer service! Their innovation in leather saddle design and its benefits are described in their white paper titled Bicycle Saddle Design Fundamentals, Research & Development 2002 – 2006

Number one on my list of most comfortable saddles is my Brook Pro modified by MCM Selle An-Atomica with the addition of their LD slot cut-out. This saddle was a pleasure to ride right out of the box and it has only got better with use. Only a few months after purchase I rode this saddle on the 2007 Bicycle Tour of Colorado and I honestly didn't even think about saddle discomfort the whole trip!

So what makes a saddle good or bad? Well my experience is that most saddles that fit the width of your sit bones are comfortable for short rides. However one needs to put a few hundred miles on a saddle over a few days before he or she can appreciate other aspects of a saddle's design that affect comfort.

My experience with rides extending of 50 to 100 miles is the amount of comfort the saddle itself contributes to the experience (This is assuming its height, pitch, and set-back are set properly!) depends on the following 5 characteristics roughly ranked by descending order of importance:

  1. Width - The back of the saddle needs to be just wide enough to accommodate the spacing of your "sit bones" for your given riding position. Both the taper or shape of the saddle and its horn need to be narrow enough to not interfere with leg movement. I am a Clydesdale that needs a minimum 155mm width, but smaller framed people may need something a lot narrower especially with an aggressive riding position.

  2. Low friction - The saddle's surface needs to be relatively smooth and slippery. The friction between your shorts and the saddle should be considerably less than the friction between your shorts and skin. Simply put, your shorts should stick to you not the saddle.

  3. Weight distribution- The saddle should deform a bit around the area the supports the sit bones in order to better distribute the load.

  4. Flex - The saddle needs to give a bit in response to shifts in position and body weight during pedaling.

  5. No pressure points - The saddle is designed so that it does not put any pressure on nerves or blood vessels that may lead to numbness or worse.

So what makes the Specialized Avatar Gel Saddle so uncomfortable for me to ride? It is wide enough. It has gel padding to distribute the load and fair amount of flex in the plastic body. It has a generous slot down middle to avoid pressure points. Well, what makes it miserable for me to ride is that it fails my criteria number #2. The back of the saddle has a suede patch stitched to either side right were my sit bones go. These patches held my bike shorts in place while I moved within them basically rubbing off skin immediately under my sit bones as I rode. The Specialized BG2 avoids this flaw by using a smooth cover, but this saddle is a little narrow for me at 150mm and I thought it might have a little too much flex.

Where Specialized's Avatar design fails
, MCM Selle An-Atomica's and Brooks' designs succeed by using a single piece of polished leather. This characteristic is so important to my comfort, I keep my leather saddles shiny by polishing them with Brooks Proofhide and a soft cloth as part of normal cleaning and maintenance.

So Brook's craftsmanship and MCM Selle An-Atomica's brilliant LD slot design combine to yield a near ideal solution for me.

Sunday, March 15, 2009

Truing a Bicycle Wheel using a Spoke Tensiometer

I have a set of Mavic Ksyrium Elite wheels with about 700 miles on them and they needed truing. Admittedly, they are a little light for my clydesdale size, but they are great wheels when I want something zippy to ride. Because of the stress I put on the wheels I need to ensure the truing solution includes careful attention to spoke tensions so the wheel will be both stable and durable.

Normally I go right to truing a wheel and only when trued do I use a spoke tensiometer (Park Tool TC-1) to identify any issues and resolve them. This time I decide it would be fun to see what would happen if I combined the spoke tension measurements with the results from the truing stand over several iterations to true the wheel.

The first thing I needed was a means to record measurements from the tensionmeter read and truing stand. To do this I decided on a simple worksheet (click on any of the worksheets below to enlarge) that could be duplicated for each iteration. Each spreadsheet is divided into 3 areas. The top left is for entry of the spoke tensions and other values. The top right is for displaying the spoke tension in a more handy format that better shows their interaction. This area is also used to record truing stand measurements and adjustment strategy. The bottom left area provides some general numbers like average, minimum, and maximum spoke tensions.

Step 1 - (Click on Chart 1) Base line the wheel's measurements using the spoke tensiometer and truing stand. Develop a strategy to improve overall spoke tension.

The wheel has a fare amount of wobble in it both deviating left and right from true. The spread in spoke tension is high and the tension is exceeding recommended 145 max kgf.

Step 2a - (Click on Chart 2) Make the identified changes in spoke tension and re-measure the wheel. Identify deviations from true and using current spoke tensions in the affected area identify new spoke tensions.

Well, in a perfect world the wheel would be true at this point, but in the real world it is much closer now to being true and stable.

Step 2b - (Click on Chart 3) Make the identified changes in spoke tension, tighten up the truing stand calipers, and re-measure the wheel. Identify deviations from true and using current spoke tensions in the affected area identify new spoke tensions.

The wheel is getting a bit more true.

Step 2c
-(Click on Chart 4) Make the identified changes in spoke tension, tighten up the truing stand calipers, and re-measure the wheel. Identify deviations from true and using current spoke tensions in the affected area identify new spoke tensions.

Closer still

Step 2d - (Click on Chart 5) Make the identified changes in spoke tension, tighten up the truing stand calipers, and re-measure the wheel. Identify deviations from true and using current spoke tensions in the affected area identify new spoke tensions.

Only small deviations from true remain.

Step 3 - (Click on Chart 6) - Make the identified changes in spoke tension, tighten up the truing stand calipers, and re-measure the wheel. Identify any changes in the current spoke tensions that can resolve imbalances at this point.

Two adjacent spokes could be tweaked to distribute the work a bit.

Step 4
- (Click on Chart 7) Make the identified changes in spoke tension, measure radial trueness and re-measure spoke tension. Identify deviations from round and using current spoke tensions in the affected area identify new spoke tensions.

The wheel has a bit of a hop in not quite opposite the valve stem hole. It is unlikely it can be removed completely because it would create too much local spoke tension, but it can be minimized.

Step 5 - (Click on Chart 8) Make the identified changes in spoke tension and tighten up the truing stand calipers. Using the truing stand carefully make minor tweaks spoke tensions to bring the wheel into complete true. Re-valuate spoke tension to determine if they are within spec. If not correct then identify the amount to loosen or tighten all spokes.

The wheel would have been finished at this point, but for the excessive tension on several of the drive side spokes.

Step 6
-(Click on Chart 9) Make the identified changes in spoke tension. Using the truing stand carefully make the minor tweaks in spoke tension to bring the wheel into complete true. Re-measure and re-evaluate spoke tensions to verify they are within spec.

The wheel is true, stable, and hopefully able to last for some time to come!

Sunday, March 8, 2009

The Workshop

Some years ago I discovered I really enjoy doing my own bicycle maintenance and found I could do a good job as long as I didn't hurry. Today I do all my bike maintenance, bike assembly, and much of my own wheel building. Someday when I have more time I may even get into frame building, but not right now.

Until recently I worked out of a large roll away and a few odd toolboxes. This was acceptable when I had just two bikes, but with the addition of 3 others using varied types and makes of components it was time to setup a proper workshop. Additionally some friends and co-workers have started seeking me out to work on their rides, so all the more the need for a well equipped workshop.

The tools were the first thing I decided to upgrade. Choosing Park for the specialized tools and Craftsman for the general purpose tools seemed to me like the no-brainer approach to ending up with a quality tool collection. Luckily I had a budget to match and could afford all but a few of the really big ticket specialized tools.

With the additional tools and goal to improve ease of access to them I considered upgrading to a much larger roll away tool chest, but decided on simple pegboard because it offers the most cost-effective solution.

Mallets have always been part of the bicycle mechanics toolbox and they will continue to be in the foreseeable future. Sometimes things just need a bit of gentle persuasion. I decided on a small mallet with one head being rubber and the other a somewhat harder plastic. These are ideal for giving things a little tap without leaving a mark.

In contrast, something relatively new to the toolbox and absolutely necessary is the torque wrench. Actually you may need two; one for light torque and one for those things that require a bit more. Why is this tool so important? Over-tightening of fasteners like bolts and nuts on super light weight components can ruin them or even result in their catastrophic failure during a ride!

Cable cutters from Park also do a fantastic job of cutting cable housing without crushing the ends.
Note the various large wrenches for bottom brackets, headsets, and pedals. A spoke tension meter is necessary when building or truing a wheel, especially one with a low spoke count. You might notice that I cheaped-out with the cone wrenches and bought a set of store-brand ones.

Nut drivers, screw drivers, open/box end wrenches, and allen wrenches are the basic general-purpose hand tools. Putty knives are handy for scraping off built-up gunk on clogs. They can also be wrapped in a shop towel clean between cogs and chain wheels. Not very visible at the botton of the picture is a couple of small single-hand trigger clamps I use as third hands when adjusting brakes. The scratch awl is great for opening up cable ends after being cut to length

The T-handle allen wrenches look pretty cool and if you need to put some serious torque on something they work pretty good. However, I will probably be replacing them with ones that have small "L" shaped handles, because the T-handles don't fit into tight places well.
A small grease gun that can be operated with a single hand is just about as handy as you can imagine. The correct amount of grease in the correct place is much better than too little or too much all over the place. The lube gets put where it needs to be and everything else stays grease-free. The bubble-level is for setting up bars and seats, but mostly seats. I like my seats flat and the level makes it easy. The tape measure is also for bike setup. Just visible at the bottom of the picture is a Park dishing tool. Don't dish a wheel without it!

Here's my truing stand. I don't have it permanently mounted, but instead I clamp it into my bench vise when needed. This allows me to maximize the use of my small workbench. I have a magnetic parts tray attached to the back of the wise to hold nipples and other small parts. On either side of the truing stand I have adjustable lamps to illuminate the rim and gauges. This makes truing a bit easier and also allows me to inspect the rim for damage from impact or fatigue. Inspecting for damage is especially important when working with high zoot low spoke count wheels!

A bike stand is a must for holding the bike while being worked on. I am currently using a portable stand because I can move it out of the way when not in use. However, I am considering switching to a stationary stand. This is because the portable stand is just too easy to tip over. This can be minimized by putting a couple of sandbags on the legs, but they tend to get in the way. A small air compressor is needed to blow the gunk out of bearings and components. It is also handy for doing a light dust off of the bike. I don't use the compressor for inflating tires, but instead I do this by hand which provides more control.

For my floor pump I decided to go old-school and get one from Silca. They have upgraded this basic pump over the years, but it still sports a retro wooden handle and it is still built to last. If the gauge were at the top of the pump it would be perfect!

Lastly, I setup a series of hooks to store my wheels and tires. That bright glow is from a Schwalbe Marathon Plus tire that has a super-reflective side wall. It is a great tire for commuters, especially when you are riding at night.

Q: How many bikes do you need?

After purchasing my latest bike, my spouse asked "How many bikes do you need?".

This is a very good question and one I was ready to answer with great precision.

Number of Bikes I need = N + 1, where N represents the current number of bikes I own.