YSFLIGHT.COM - Rest in peace, my excercise bike.

I started diet last December. Actually, not really diet. I have been trying to lose weight by increasing exercise. No dietary restriction. I have been following dietary restriction for kidney-stone prevention, but I didn't add any more restriction for losing weight. For the first 6 months, I lost 2 pounds per month. I think it was a good pace because I was just a little bit overweight but not obese. Since I was in Japan and could not exercise much in July, it took two months to lost another 2 pounds.

My primary goal was to lower my blood uric acid level. My former family doctor told me that my uric acid level was higher than normal, and losing weight is a good way of reducing it. Also, I rent and fly a Cessna 172, which can carry three adults including the pilot. If three adults are on board, the airplane is almost at the maximum take-off weight. If I cut down 10lb, the airplane can carry 10lb more baggage. It's critical when I fly to Columbus OH for grocery shopping. (Yes, I have flown for grocery-shopping at least three times.)

I really didn't have time to do exercise before. Mainly because I have too many hobbies. I do programming for fun (not just for real work), taking pictures of birds, going to air shows, flying an airplane, bowling in a local league. To do exercise, I needed to cut something. In the last fall semester, I had teaching on top of all of these, and I really couldn't work out. I ended up gaining 6 pounds in 6 months.

The solution was an exercise bike. I bought this exercise bike called Gold Gym Power Spin 210 U a few years ago. I used it often just after buying it, but when I got too busy, this exercise bike had another mission of drying clothes. To restore its original mission as an exercise machine, I mounted a cooking plate, put small keyboard and a trackball on it, and made a truss structure to hold my laptop. This way I could work on something while doing exercise.

Gold Gym Power Spin 210U

Laptop Mount

With my ThinkPad X230T

I didn't do anything sophisticated. I cut some wooden bars that I bought from a hobby shop, drilled holes, and tied them together with cable ties.

I could reply to E-Mails, prepare for the lecture, and even programming. I wrote substantial amount of YSFLIGHT code on this exercise bike. With this I could work out for an hour a day.

After working out for an hour, I totally get soaked by sweat. According to the panel, I was using 300kcal in an hour. It was as same as slashing two small bowls of rice every day. It was interesting to see how my body weight going down. It was not a smooth and constant change, but my weight stayed the same for a few weeks, and then suddenly dropped by 2 pounds or so. I started working out December 20 last year, and for the first six months, I lost 2 pounds per month. I didn't lose much weight while I was in Japan in July, but I lost two pounds in July and August total. (I was measuring my body weight before going to bed by the way). Over all, I lost 15 pounds in 9 months. My body-fat ratio dropped from 25% to 20%.

(Since I haven't written any research paper this year, losing weight has so far been my biggest achievement of this year.)

But, achieving 15 pounds reduction was not a smooth way. I'm not talking about determination. I'm talking about the mechanical problems of the exercise bike. First trouble was a broken battery-lid. Power Spin 210 U has a flawed battery lid. This lid was poorly designed and the pin easily breaks. If one pin breaks, the lid cannot hold the weight of the size D batteries, and cannot power the console, means I cannot control the resistance. If I had a 3D printer, I would have printed. I think 3D printer will be used for making this kind of plastic part soon.

I could have given up on this exercise bike and bought a new one. But, the problem was only battery lid. If I held the lid by hand, it powered up, and everything was working. I don't like to throw away things that still works. I tried to fix it.

I first tried to hook a 6V AC adapter. But, Power Spin 210U's console seemed to be doing something strange inside, and it didn't accept an AC adapter that I bought from Radio Shack. So, I disassembled the console, and changed the wiring so that it can be powered by my AC adapter. At one point, it even stopped working with size D batteries, but I finally figured and made it work with my AC adapter. Actually the AC adapter connector had a loose connection, so I also lead two wires for power that I could fabricate a new connector in case the connector totally dies.

Red and black wires are for additional AC adapter port.

Well, before the AC adapter connector died, the bike itself broke though.

My exercise bike was alive again after my surgery. But, it got another problem. It started making a noise like choking and killing a pig. Clearly, some metal parts were scratching. In addition, it made a noise like crushing something. I suspected that the bearing was breaking. If the noise got worse, I was thinking to give up. But, after riding for a few days, the noise was gone. Instead, the bike started vibrating. The vibration caused the plastic casing hitting the metal framework, and made even louder noise. Solution was inserting rubber bands between the plastic casing and the metal frame. The bike was operational again.

I think it was sometime in June. It had been working three months since then. However, since a few days ago, the bike started to make noise like a bicycle out of lubrication oil. Also the pedal resistance occasionally got too heavy. Something was falling apart again.

For the last attempt, I applied WD-40 to the axis. The noise got slightly smaller. But, it started vibrating wildly. I applied WD-40 again, then some oil with rust seeped out of the axis. The last hope gone.

Oil with rust

I disassembled the bike, and then saw steel powder under the bike. Clear sign of metal parts ground over the years. This guy served me well and made me lose 15 pounds. I thanked the bike for the last time, and disposed it.

Steel powder leaking from the plastic casing gap.

For the replacement, I drove up to Walmart and bought Power Spin 290C, which I believe a newer model of 210U. This guy doesn't have a design flaw of the battery lid. Assembly was straight forward, too. Only concern is that its resistance is much heavier than 210U. If I set the resistance level to level 3, it's almost same as level 7 of 210U. I hope it is not defected. So far, after using two days, everything other than heavy resistance looks normal and smooth. I'm hoping to drop another 10 pounds by next spring.

New Power Spin 290C.