Tag Archives: Repair

What’s underneath?

People ask me what the Leitra velomobile I ride is like under the fairing. Here are two pictures of the frame that I took last time I was doing maintenance on the bike and had all the fairing pieces and seat removed.

Leitra frame front

Leitra Frame front

From the front, you can see the two piece, carbon fiber leaf springs for the front two wheels. The “Y” shaped bit at the very front is where the front fairing attaches and pivots for entry and exit. The seat snaps into the frame just ahead of the rear wheel. In the center of the back of the bike is the rear wheel which sits inside a wraparound fender that keeps water, snow and dirt out of the seating area.

Leitra frame rear 3/4

Leitra frame rear 3/4

From the rear, you can see the Bionx electric motor assist. It consists of the linear motor hub in the middle of the rear wheel and the battery mounted under the left arm rest. The cargo area of the fairing sits above the rear wheel on the rack-like extension. The “V” shaped parts in the middle of the rack and two small strips on either side of the rear wheel are carbon fiber leaf springs for the rear wheel.

The frame is hard to pickup and put on a work stand, so I usually just hang it from my work stand with a loop of rope as shown. This lets me turn the rear wheel and adjust the derailer and lube the chain.

Replacing a harddisk in a Mac Mini Server

Behind the scenes, my household network services are provided by a pair of Apple Mac Mini Servers, one for internal services (DNS, DHCP, file sharing, backups) and one for external services (DNS, mail, web hosting, ownCloud). I also have an older Mac Mini attached to my home theatre. I like the Mac Mini’s a lot. They are inexpensive as servers go, draw little power, and are quiet, cheap and reliable.

Apple Mac Mini Server

Apple Mac Mini Server

Sadly, the internal server’s boot disk died a couple of weeks ago. It failed slowly over a couple of hours and thankfully did not corrupt the server’s time machine based backups on its way out. I have prepared for this eventuality by keeping a cold spare  in the form of an older Mac Mini that sits on the shelf, ready to be put into service if one of the active Mac Minis has a problem. So, after an attempt to resuscitate the dying hard disk, I gave up on it and restored the most recent backup of the server onto the cold spare.

The restore process is pretty simple. First, I choose to boot the cold spare from a USB key that I had prepared with a bootable installation image of OS X Mavericks. I used the included script that’s buried in the Maverick install image to create the bootable USB key. The directions for using it can be found from Apple or with a bit more detail from MacWorld. You will need to have either saved, or downloaded the current Mavericks installer before you follow those instructions.

Once the USB key and cold spare are ready to boot, I booted with the “option” key held down and picked the prepared USB key from the list of available boot devices. When restoring a server with more than one disk, you need to do a little bit of extra work to restore the second disk before you start the restoration of the boot disk as detailed in this Apple Knowledge Base article. After restoration, the cold spare booted up without problems. I corrected it’s network settings (it has a USB ethernet connection, long story for another post…), checked that services were running, “inherited” the current time machine backups and my internal services were back in operation.

Next up, I ordered up an SSD to replace the failed disk. SSDs have come a long way in terms of reliability and are well worth the added expense given the marked speed improvement they offer. I chose a Samsung 750GB EVO 840 drive based on the recommendation of the good folks at Mac Mini Colo. I bought the drive from OWC and followed their installation video. The install is indeed “challenging” and took me about 90 minutes.

Mac Mini Disassembled

My Mac Mini disassembled

A word of warning, I ended up doing the disk installation twice due to pulling the wrong drive the first time. If you can, before you remove the dead disk, look at the system with disk utility which will indicate which drive bay (upper or lower) a disk is located in. That would have saved me some time.

The server with the SSD has been running for a few days now without problem and I plan to swap it back into production service, using the same time machine restoration process, this weekend.

The Rest of the Fall Leitra Maintenance

I’m cleaning up my electronic files and realized I had a few pictures from my other fall Leitra maintenance that I had not posted, along with some notes on fixing a shifting problem with my SRAM DualDrive 3 speed hub plus de-railer.

To start with, it’s easiest to strip the fairing off of the Leitra to work on the drive train. It’s buried inside all that fiberglass to help protect it from the weather and keep it clean. The fairing is four parts. The nose and window section that tilts up for access, the upper tail box and side curtains and a two part lower tail box that provides some storage that is accessible from inside while you are riding. Here are pictures of the Leitra with the nose and tail box removed.

Leitra w/o nose & tailbox

Leitra w/o nose & tailbox

Leitra w/o nose & tailbox, another angle

Leitra w/o nose & tailbox, another angle

The major item on my repair list was to figure out why the 3 speed hub portion of the DualDrive was “stuck” in under-drive and would not shift into pass-thru or over-drive. The DualDrive has a “click box” that handles the 90 degree turn from the shifting mechanism inside the hub to the cable that runs to the hand grip shifter. Here’s a picture of it mounted on the Leitra. You can see that rear wheel sits inside a full coverage fender that extends down to a lip that protects the chain and de-railer arm from spray coming off the rear tire. The “click box” is circled in red.

DualDrive on Leitra

DualDrive on Leitra

The “click box” can be removed by setting the shifter in “low” or “under-drive” and pushing the black button on the box. This reveals the long bolt that goes into the shifter mechanism. This was surprisingly loose, which made me think I had found the problem.

A little Google searching later, I found that, indeed, that bolt needed to be firmly tightened for the hub to shift properly. I tightened the bolt up and then adjusted the shifter. The “click box” makes this easy with a little alignment window and a yellow indicator. The arrow in this next picture points out the alignment window. The yellow indicator should be in the yellow outlined box when set correctly.

Clickbox window

Clickbox alignment window

Once I had the shifter aligned, I had all my gears back!

I use the SRAM DualDrive in two ways when I ride.

On longer rides, I use the 3 speed hub like you would use the pedal chain rings, for large adjustments in the gear range. I use the de-railer for smaller adjustments.

But in traffic on my work commute, the 3 speed hub’s ability to shift while not in motion is a big asset. I tend to simply shift the 3 speed hub, ignoring the de-railer when going stoplight to stoplight because I can quickly drop down to low gear when stopped.

Needless to say, I’m glad to have the hub back in working order!

New Taillight

I’ve started preparing the Leitra for this coming winter. One thing I’ve wanted to do for a while was replace the low-powered taillight. The original light had 2 LEDs and wasn’t as bring as I would like. After a bit of searching around, I found a 5 LED light that uses higher brightness LEDs and offers several blinking patterns. Most importantly, it came with a mounting bracket that fit in the narrow space in the tail box lid. Here’s what it looks like from inside and outside.

Taillight from inside the tail box.

Taillight from inside the tail box.


New taillight from the outside.

New taillight from the outside.


New taillight from outside and above.

New taillight from outside and above.

Don’t know my own strength

On the way into work Wednesday morning, I pulled up to cross State Street, just a block from my office in Young Graduate House, a high rise dorm that’s been converted to office space, and as I pushed off I felt the seat back on V-Rex sag and something poked me in the side. Uh, oh. On brief inspection, I could see the seat was moving free of the cross member that mounts it to the sprint braces. WIthout that support, the seat (and therefore the bike) was out of action. Thankfully our van was empty and my wife graciously came by at lunch and helped me take the V-Rex back home. Today, I got down to figuring out what happened and fixing it.

Rans SeatThe Rans seat was one of the first really popular recumbent seats, appearing not only on Rans products, like my V-Rex, but also on other companies bikes as well. It is a large foam covered triangular base, with a cross braced, mesh fabric covered frame for a back. It attaches to the bike at the seat bottom and to sprint braces which usually go back to the rear triangle. The attachment points are marked by arrows in the picture on the right.

The upper mount point is part of a cross brace between the two vertical tubes that make up the seat back. The pop rivets that hold that in place had failed and cross piece had come free.

Cross Piece

After drilling out the failed pop rivets, and banging out the slight bend that one of the sides of the cross piece has acquired thanks to that last push off, I was able to pop rivet the piece back where it belonged. Then I put the seat back on the V-Rex and adjusted the tilt and distance from the pedals to fit myself.

I like the sliding seat back arrangement on the V-Rex better than a sliding pedal tube for several reasons. First, it’s simple to adjust. On the V-Rex the slide is help in place by a quick release skewer. Second, there’s no chain adjustment that needs to be performed whenever the seat is moved.

I’m looking forward to being back on the V-Rex come Monday’s ride to work.