Alex Wetmore is always busy with something…

Mark Vande Kamp and I were out for a ride last night and had a conversation which gelled some of my recent thoughts.

I can really only motivate myself to ride when I have a destination in mind. For me this really boils down to two types of riding. Commuting and touring.

In 10+ years I’ve never been much of one for just getting on my bike and riding 20/50/100 miles and ending up at home again, especially if I’ve done the ride before and I’m just riding solo. I don’t really feel like I’ve acheived anything but fitness, and cycling is about more than fitness for me. When I think back on my “just go out for a ride” type rides the enjoyable ones either all had a purpose or were more social events than riding.

Commutes I can do solo. The long form of my commute is 25 miles and I ride it a couple of times a week in the spring and summer. There are two routes to take and both are enjoyable for different reasons. The medium length commute is 10 miles and I do that on my other days. This makes it trivial to rack up 80-100 miles of riding every week during the summer. I also use the term commute lightly, commutes include any riding where I’m riding from one point to another. Riding to have dinner with friends? Riding to the grocery store? Both are in the rough “commute” area for me.

This year I’m making a big push back towards touring. I kicked it off with a overnight ride with the point83 club a few weeks ago. I hope to do one overnighter per month through the summer. In July I have a week long trip planned with Larry and John (my normal touring buddies — Larry and I have been doing week long tours for almost a decade). Touring is the ideal pleasure ride — I have a destination, there are no repeats, and the tours often involve riding with a friend or two.

This weekend I have two destination rides planned. Tonight I’m riding to a friend’s cobb pizza oven party. Sunday I’m going on Ro’s cargo bike ride to have a memorial day picnic in West Seattle.

Alistair showed me photos of his rack jig a couple of months ago and I finally got around to building one myself. The core piece is some sort of holder that we got at “Science, Art and More”, a fun science oriented store in Seattle. It consists of two tube clamps with a center pivot that can be rotated 360 degrees. Alistair added two other tube clamps on stalks, one for the frame or fork and one for the rack top. Using this you can position the rack top while you braze in the stays that will hold it in place on the bike. Click the image for more photos.

After building the jig I added the fork crown mount to one of my rack tops. I like how this one came out:

The bolt that goes through the fork crown is just a standard steel M6 bolt bought from my local hardware store. I cut off the head and brazed it to some 1/4″ tubing. Finally I put a 5/16″ sleeve around the bolt to provide something for the nut to compress against.

Nothing groundbreaking, but it is a little smoother looking than the similar design on a Nitto M12.

Yesterday I made my second small front rack top and it was the second time that I had trouble with the measurements for bending tubing (using a lever-style bender). While sitting down with a piece of scrap and the bender I figured out an alternative way to compute bends.

Swagelok has a the best manual for lever benders that I’ve seen. The information is good for any brand of lever bender (I have two benders, neither is made by Swagelok). Starting at page 13 there is a discussion on the gain calculations for figuring out where to place bends for making a polygon.

I’ve had problems with the Swagelok method ofcomputing gain because asmall mistake anywhere in the process can cause problems elsewhere. Yesterday I made either a computation or measurement error and madeone bend 1/2″ earlier than I should have. I ended up splicing twopieces together to recover. Since the Swagelok method has you map out all bends before you start any small errors at end bend will compound.

I figured out an alternative that is easier for me to use.Instead of marking only the end of a bend I’m marking both the start and end of each bend and measuring the straight section of rack between the bends. Using the bender radius I can compute the desired lengths of the straight sections.

In this example I make a roughly 5×7 rectangle (good for a handlebar rack) out of 1/4″ tubing using the Ridgid 404 bender. It has a 5/8 radius.

For a 5×7 rectange the long straight sections would be 7-(5/8)-(5/8) = 5.75″ and the short sections would be5-(5/8)-(5/8)=3.75″. To make life a little easier I rounded these up to 6″ and 4″. The rack will be 5 1/4″ by 7 1/4″, which is still a good size.

Using the radius of the bender I can compute the circumference of the bend that I’m making. For a 90 degree bend it is (pi*2*r)/(360/90). r is 5/8, so this gives me .98″.

The Process:

In this example I’m going to put the seam along in the center of one of the ~5″ sections.So I measure 2″from the end of the tubingand draw a line. .98″ from that lineI draw a second line. To bend I align the first line with the 0 point on the bender. After a 90 degree bendthe second line will mark the start of the new straight section.

I continue this process working around the rack. This photo shows us at the halfway point.

At the final bendIdo the same thing, but I also do something else to check my work. Using a square aligned with the center of the first piece of tubing I draw a third line in between the two normal ones. I put a S through it (square) making a $ sign. You can just barely see this in this photo, but it is clear in the next one.

The $ line will line up with the 90 degree mark on the bender:

I cut the tube to 2″ past the last line and bend:

Here is the final product:

It is about 5 1/4″ across (center to center). We used 4″ straight sections and the bend radius is 5/8″. 4″ + 5/8 + 5/8 = 4 10/8″ or 5 1/4″.

You’ll notice that I never had to measure any fractional numbers except for the bend circumference. I set your calipers up to the bend circumference and locked them in place. This let me use the ruler for the straight line measurements and the caliper for the bend marks.

The same technique should work for non-90 degree bends, you just need to figure out the circumference of the bent area. The formula is simple: (pi*2*r)/(360/degrees). So a 60 degree bend with a 5/8″ bender would be (pi*2*(5/8))/(360/60) = .65 (or 21/32nds). I’m going to be building some front lowrider racks with trapezoidal shapes next and will use this technique there.

On Sunday a group from Point83 got together at a local bikeshop and re-raked some forks. Val Kleitz (used to own Bikesmith and bike mechanic extraordinaire) was there for a couple of hours to lend some advice.

The goal of re-raking the forks was to add additional offset to decrease the bicycle’s trail. This improves the bike’s handling when riding with a front load, even a small one like a handlebar bag.

I brought 4 forks to re-rake:

1,,,,) A Jamis fork that was supposed to be disposed of anyway. It was built about 1.5cm too short and replaced under warranty. I did this fork first because I didn’t care what happened to it.

2) A 1986 Trek 400 fork. I’ve been trying to sell this at the Seattle Bike Swap for $5 or $10 for the last 3 years with no interest. I don’t own the frame that it was on any longer. It will have cantilever bosses installed for 650B and available as a low-trail demo fork to friends. It is already too short for 28mm wide 700C tires with fenders.

3) A 1983 Trek 630 fork. This fork has 25,000 miles on it and needs to be repainted. I reraked it the least, changing the offset from 10mm to 20mm.

4) A 1994 Bridgestone RB-T fork. This is from my RB-T, one of the ugliest in existance due to being touched up at random spots with purple nail polish by a previous owner.

Point83 and BOB list member Andre also brought a early Trek mountain bike that he was using as a load hauler with a large Wald basket. He wanted to re-rake this bike’s fork to have a trail of around 40mm for carrying heavy loads.

We primarily used two tools to re-rake the forks. A Hammill fork blade bender was used to increase the offset in each fork’s blade. This bender has a radius of 10″. Using the fork leg bender does take the fork out of alignment, so we used a VAR fork alignment jig to realign the fork after getting to our target offset.

Val showed us a great trick for checking fork offset. Draw a line on a sheet of paper and place the fork on the paper with the dropouts aligned along that line. Use an angle finder (or bubble level) to hold the fork’s steerer tube at 90 degrees. Now look down the steerer tube of the fork and down a line on the paper along the center of the steerer. This is easier and more accurate if one person holds the fork while the other looks through the steerer. If you measure that to the reference line for the dropouts you’ll get the fork offset. I checked this with two forks that I knew (the published) offsets for and the results were accurate. Andre drew this great drawing that shows how it works:

The bending worked for forks with no canti bosses or canti bosses set for 700C wheels. When we tried to bend Andre’s 26″ MTB fork we found that the canti bosses were placed too low and ran into the mandrel of the bender. This fork was re-raked using a Park leverage tool.

Even bending with a normal radius the fork height didn’t change too much. It was pretty easy for me to measure the Jamis fork (I had a reference wheel/tire which just barely fit before) and the dropout to fork crown changed by about 3-4mm when we increased the fork offset by 20mm (going from 45mm to 65mm).

This photo shows a stock (in grey) 1983 Trek 600-series sport touring fork and a re-raked one (in gold) which has had 10mm of offset added to it.

With these two photos you can see that the tire clearance did not decrease too much when adding rake to the fork. The tire is a 700×35 Panaracer Pasela, larger than what I’d use with these bikes. Tom Matchak’s article on re-raking gives you the math for figuring out how much the fork length will be reduced through re-raking. Note that his measurement is along the steerer and overestimates the amount of clearance lost in most cases.

I spent some time on Saturday experimenting with different headlight mounts on my bike racks.

This is the first attempt. It is just a M5 eyelet on one of the rack stays. Nitto uses something like this on the M12:

It’s a basic but functional solution. The small piece of flat stock gives one a lot of options for where to actually put the light. It looks pretty ugly though. The best part about the light mount on this rack are the three loops for managing the front cable. No zipties here! They are made from rollers pulled from a worn out bicycle chain.

On my convertable Porteur Rack I played with two different options. The first (no light mounted to it in these photos) is a pretty basic design that is easy to make. I just used some 5/16″ tubing with a perpendicular piece at the end for the light’s mounting bolt.

I also need a mount on this bike which is farther back so that it doesn’t interfere with the front wheel hook on a Sportworks bus-mounted bicycle rack. I thought of a nicer and more simplistic option here. I used the shaft from a nail (about 3mm in diameter) and put a 5mm eyelet on the end of it. Minimalistic and functional, I like it.

While I had the torch out I filled in all of the vent holes on my front rack with small nails and brass. That was a lot of work, but now there is no way for water to get in:

This was my second Critical Mass ride. The first was in July 2006, a month after illegal arrests on the June 2006 ride. July 2006 was a huge ride with hundreds of riders (maybe 500) and a supportive police escort. I knew that one wasn’t typical so I thought I’d go again.

For years I’ve been anti-CM without having gone on a ride. In July I learned that the rides are tons of fun. Friday’s ride was great fun too. It’s a massive celebration of bikes and bike culture. All types of cyclists come out. My favorites are the ones who do something extra to their bikes for the event:

Sebastian was pulled 15 miles or so in this trailer and provided refreshments to those in need.

Human powered music on a human powered ride. Another group brought out a sound system and hauled it on a trailer behind a tandem.

The celebration is great and bigger than the ride itself. We did ride (loop around downtown, Elliot/15th out to Ballard, ending at Gasworks), but the route isn’t what was important. I think that the public is startled, amused, and generally sees fun when they see a huge collection of folks riding down the road, playing music, talking, and having a good time on bikes.

I’m not as keen on the traffic blocking aspects.I don’t think it helps with the message that I want to send (bikes are fun and practical means of transportation) when CM blocks intersections and prevents other forms of traffic from getting through. I like the idea of a mass and don’t like seeing it break up, but I also like traffic controls and don’t want to send the message that cyclists should ignore them. Part of me would love to see a different type of CM where traffic laws are obeyed and the group naturallybreaks up and rejoins at different places around the city. Maybe it would work, maybe it wouldn’t. CM is well established and I like most of what it is about. I’m going to embrace those aspects.

I’ll be there next month for the party. I hope to see you there too.

Many more photos.

This will be the last rack posting for a little while, until it is actually complete.

(click for more photos)

I installed the other stay and a backstop last night, cleaned up the flux, and mounted the rack on my bike. I only used it for a short ride this morning but it seems to work very well. I was worried that my stays were too far forward and would cause problems with the front wheel hook on the bus rack, but it wasn’t an issue.

Remaining work:

• Install a light mount. I think I’m going to get a Lumotec Oval and mount it between the stay and the wheel. It looks like there is enough space.
• Wire routing for the light.
• Fender eyelets (so the fender mounts to the rack)

The bike handles nicely with the front bag. This isn’t a surprise since it is a lower trail bike (45mm trail). There is a small amount of shimmy when riding no hands, but this will probably go away if I drop the tire pressure a little. I normally ride these tires (28mm Avocet Duros) at 75psi but they are at 90psi right now.

My vacation put a little hold on my rack making, but this week I did get to spend a few hours in the workshop. The gallery is updated.

I’m pretty happy with the progress for a first rack. I wish I had spent more time when making the bends for the rack top, some of them aren’t perfect and it makes the whole thing slightly wonky. The top has a slight twist in it when viewed from the front, it doesn’t all lie in a nice plane. It’ll definately be functional but it might not be pretty.

I’m pretty happy with how the mount to the fork crown came out. It is tricky to get everything to fit when you use a sidepull brake (instead of cantilevers). I should have left my mock-up brake on for the photos.

The other challenging part has been coming up with fixtures for holding things in place while I braze them. I built the rack in this order:

• Make the top
• Make the fork crown mount
• Attach the fork crown mount to the top
• Make and attach the stays to the top
• Make and attach the backstop to the top

Attaching the fork crown mount to the rack top was tricky. I did it by mounting a wheel (no tire) into the fork and putting a long and skinny piece of wood onto the wheel (coming off at a tangent). The end of the wood had a groove which held the front of the rack at the centerline. I useda ziptie around a spoke and the fork blade to keep the whole thing in compression. The rear of the rack was held against the mitered fork crown mount using this compression.

How do others do it?

I finally made the plunge and bought the equipment necessary to braze racks out of steel. I spent a lot of time asking Alistair, framebuilding members, and random people at NAHBS what I should buy and finally ended up getting a Victor Superrange II. The torch is a little bigger than ideal, but the price for the whole kit was a lot cheaper than putting together my own kit with good regulators and a smaller airplane torch. The included regulator was also compatible with propane (I’m using Oxygen/Propane instead of the more common Oxygen/Acetylene). I also bought a Ridgid 3/8″ tubing bender, stocked up on files, and ordered a bunch of tubing from Aircraft Spruce.

The first project is a handlebar bag rack for my Trek road bike. It has caliper brakes and I’m not crazy about the common designs for racks that would fit.

Tonight I got home and built the platform:

It’s not perfect, but it’ll be perfectly functional. I messed up when measuring the platform and was off by about 1/4″ where it the two ends of the outer tubing join each other. I brazed in a little filler piece of tubing to make it work. The joint isn’t perfectly smooth, but I think it’ll be okay after I sand it out. The perimeter of the rack is made out of 3/8″ tubing because that is what works with my bender, but I’m using lighter 5/16″ tubing elsewhere. Click the picture to see more photos.

I’m excited about building some more and finishing up this. I think my second project will be a good lowrider rack for my Bike Friday, the stock one is terrible.

Lessons learned so far:

• Measure carefully when making the perimeter for a platform
• The flux that Henry James sells is much nicer than what I picked up from the local welding store. I can’t wait for my HJ order to arrive.
• Measure more carefully when trying to make things look balanced. My middle-stay is slightly off center.

Two weekends ago I went to the North American Hand Made Bicycle Show (everyone just called it NAHBS) in San Jose. It was overwhelming and wonderful. I met many great people (builders and visitors — we had a nice lunch on Saturday with a lot of people from the Internet-BOB list).

I have hundreds of photos here:

http://alexandchristine.smugmug.com/gallery/2545060#133876019

This past weekend it was time for the Seattle Bike Expo. I wasn’t super excited about this one, but I did want to stop by and visit Jeff Lyon and see if any other builders showed up. Jeff and I had a nice conversation and also I ran into Val Kleitz (ex-owner of Bikesmith, my favorite bike shop), Kathleen from Free Range Cycles, and some other folks. Sadly I didn’t get to spend too much time at the show and I had to head back before getting to see all of it. Photos from the Expo are here:

http://alexandchristine.smugmug.com/gallery/2576055#135655933

Finally, I just need to plug this really nice new randonneuring bike that Jeff Lyon built:

68mm of fork offset, 650B, custom racks, nice fenderlines, a beautiful paint job by Keith Anderson, and a nice build. It really came together nicely.

alex