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Categories: all aviation bicycle gadgets misc motorcycle theater
Thu, 30 Apr 2009The last few weeks, I keep finding myself not sleeping very well. One of the reasons is that I'll be mulling over a mechanical or design problem as my mind wanders from topic to topic, and I get stuck on it. A week or two ago, I woke up to the realization that I'd designed quite a workable folding welding table, having worked out the offsets in the hinges to get it all to fold up nicely. This morning, I woke up to realize that I'd been running over the process of machining these velocity tubes Michael made and showed me:
I'd worked out, in my sleep, that by his description, their length was predetermined by the angles he'd chosen to cut them at (3° for most of their length, 9° for the last bit, and 6° to smooth the transition from 3 to 9), although that length was longer than what he made. It's a bit odd to wake up and realize how much work I've been doing while, at least in theory, resting. This might explain why I've been feeling a bit sleep-deprived lately. Posted at 16:56 permanent link category: /misc Tue, 28 Apr 2009I had an early day today, and decided at the last moment to stop by Online Metals to see what they had in their cutoff bins. In actual fact, they had a great deal, and the only thing that kept me from going crazy is the fact that whatever I bought, I'd have to cart it home in my shoulder bag. Even with this constraint, my back hurts from the 13 lbs of metal to which I limited myself. Specifically, I got metal for two interesting projects. The first is for the street CL175: footpeg relocation. The footpegs on the CL175 are provided by this heavy steel bar which runs under the frame. You can kind of see it here: 
The main footpeg is the bigger one, on the right. Anyway, that peg is in a weird spot for me -- I really expect my footpegs to be further back, and a bit higher. Well, for the race bike, I ended up making these thick steel reinforcement plates for the passenger pegs (further back, and folded upright in the picture above); why not make new reinforcement plates like on the race bike, but extend the plates down a bit? That would put the pegs exactly where I expect them. It would require some extra engineering for the shifter and brake pedal, but that's nothing I haven't solved before. So, I picked up some more 1/4" thick steel plate to make those peg relocators. The other project I have in mind for the latest haul of metal is velocity tubes for the race bike. Fellow racer and inveterate tinkerer Michael Bateman made up some velocity tubes for his development bike, and forwarded me the dimensions -- no problem to make. That would be a fun project that might even make a practical difference: velocity tubes smooth the airflow into the carburetors, which should at least theoretically allow the engine to run a bit more efficiently. As I understand it, non-laminar airflow into the carbs reduces the amount of air they can suck in per piston cycle, which reduces the amount of air-fuel mix, which reduces the amount of power possible. It's probably not a difference I'd see on a dyno so much as while riding (with the attendant moving, chaotic airflow), but I also don't race on a dyno. Now, of course, I find myself wanting to read up on the design of velocity tubes, to see if I'm headed in the right direction. If so, I've got enough metal to make 3 pair of tubes, I'm pretty sure. Posted at 17:28 permanent link category: /motorcycle Tue, 21 Apr 2009Being, as I am, interested in matters of safety and public perception, I'm thinking of running a brief study. I propose to sit at a popular four-way-stop intersection in Fremont, at 34th and Evanston, outside the PCC, and record who stops. The vehicular categories will be: car, bicycle and motorcycle. The types of stop will be: full stop, rolling stop, pause, and ignore. I will observe for a set period of time, probably 15 or 30 minutes, just to get a feel for what's actually happening. This is an intersection which gets a fair amount of traffic of all types, including a lot of bicycles. Once collected, I'll publish the data here. I would be very interested if others wanted to join me in this task: pick yourself an intersection, and record who does what for a while. For clarity, let me define my terms: Car: any enclosed, three-or-more wheeled vehicle, powered by something other than human power (ie, gasoline, diesel, electricity, etc.). Motorcycle: any open, two- or three-wheeled vehicle, powered by something other than human power (ie, gasoline, diesel, electricity, etc.). Bicycle: any open, two- or three-wheeled vehicle, powered primarily by human power (including electric-assisted bicycles). Full stop: coming to a complete stop so that all forward motion is ceased. A bicycle track-stand counts as a full stop, since the bicycle moves backwards. Rolling stop: slowing to a near-stop without actually eliminating all forward motion. Pause: slowing for the stop sign, but not coming to a near-stop. This is a judgement call on the part of the observer. Ignore: rolling through the stop sign without significantly slowing down. As I was planning this study, walking back from about 5 minutes observing this intersection, I watched a motorcyclist with a severely under-clothed passenger, roll through a stop sign as if it didn't exist. Nothing like motivation, eh? I would also like to say that this study is not intended to promote the stop sign as some kind of godlike traffic safety device. I actually find stop signs fairly annoying in their profusion (visit Europe, and you'll be hard pressed to find a stop sign anywhere). This is a study to see who's paying attention, and who's obeying the laws we have. Posted at 13:16 permanent link category: /misc And people seem boggled when I yell at them for riding their bicycle through a stop sign:
From Facebook, today. Reasonable, non-violent people react to bicyclists. Posted at 11:02 permanent link category: /bicycle Thu, 16 Apr 2009In the last few days, I've been working pretty hard at making theater happen. If you haven't been following along, I'm designing lights and doing photography for Love's Tangled Web, at Annex Theatre. I'm also doing a ton of other little tasks, as always happens in fringe theater, but that's neither here nor there. In a normal production, I'd expect to be doing the second full run tonight, the night before opening. I'd still be frantically chasing down problems in the lights, both the plot and cues. If I was a clever monkey, I would have taken the week off from work (I usually figure this out a few days before the week I should take off, which always makes me feel like a moron). I wouldn't be panicking, but I wouldn't be all that far from it. One of the reasons I've never written about this stuff before is that it's so overwhelming at the time that I simply don't have time to sit down and write about it. As I've cleverly implied, I am not in that place of near-panic now. This show has gone amazingly well, all the way from the meet-n-greet until now. Things have happened on time or ahead of schedule. We're getting our 6th(!) full tech run tonight. People have been delightful to work with. There have been no big clashes of ego, and no disasters, whether ego-induced or not. My employer even declared a week of vacation (to get us to burn off vacation hours) this week, the perfect time for me to have a week off. We open tomorrow. Thus it was that for the last few days, I've found myself walking out to get dinner at some reasonable hour, a feeling of contentment settled upon me like a cloak of finest ermine. All has, for quite a while now, been right with the world. It's a fantastic feeling. Of course, I'm still busy as hell, but I'm not freaking out. Nothing feels like it has to be rushed. It's all just... ok. Oh, and I suppose I can't tease you about photographs without offering up some evidence of the photographic goodness. Click on the below picture for a gallery of photos that we're sending out to press, and feel free to share them yourself: Posted at 16:56 permanent link category: /theater Fri, 10 Apr 2009
That default standard picture set
Enjoy! Click on "High Res" for 14.7 megapixel versions Posted at 15:15 permanent link category: /motorcycle After a gonzo few hours spent fanatically measuring the CL175's clutch, and consulting with one Michael Bateman, we determined the problem: the previous owner of my bike had put in the wrong clutch parts. Michael, inveterate tuner and hopper-upper that he is, has replaced more clutches than god, and had some spare, correct-size clutch plates for me. He sent them along, and I got them on Wednesday. In a brief fit of madness, I installed them after I got home that night -- of course, I didn't get home until 11 pm, which is so far past my "Do not start in on new projects" hour that it's not even funny. However, the job was easy, and I was done half an hour later. Today, I finally had winnowed enough free time out of my schedule (mostly by missing sleep) to get oil poured back into the engine, and the footpegs reinstalled. I fired up the bike and gave it a few test-runs along the shoulder, and the clutch felt just right. I decided that it would be worth riding it into work today. The trip was effortless. It's amazing how much of a psychological difference a correctly working clutch makes. The engine and transmission are always connected when you expect them to be. There's no limit on how far you can hit the throttle before you have to worry about breaking the clutch loose. The bike is suddenly grounded and centered. I'm still floating on the happy cloud of working-clutch, which is delightful. I think I might even take the bike out to my traditional photo spot (which has been disrupted by years of construction), and take my now-traditional round-the-bike photo set. And, happy day, I have the new G10 to do it with. It's all coming together. Posted at 12:14 permanent link category: /motorcycle Thu, 09 Apr 2009In a brief fit of madness, I thought of a cool picture. In a longer fit of madness, I ran in to grab the camera and a tripod, and actually take the picture.
Posted at 14:07 permanent link category: /motorcycle Wed, 08 Apr 2009At the Love's Tangled Web load-in this weekend, I ended up capturing more neat photos, two of which I wanted to share here:
Max is the Annex tech director, and was instrumental (ah-hah, oh, that's a joke most people won't get) in getting load-in finished quickly and efficiently. The bad joke is that each of those fancy light-casting thingies we put up this weekend aren't called "lights," they're called "instruments," like "lighting instruments." I know. Shoot me now. Posted at 08:49 permanent link category: /misc Mon, 06 Apr 2009My exultation at the clutch being fixed on the CL175 were, let us say, premature. Possibly foolish. Turns out that when you run a wet clutch without oil, its grip increases. Who woulda guessed? Indeed, when I checked the oil after that oh-so-successful run, it was off the end of the dipstick. This is disturbing, as I'd checked it before, and it was in the middle of the range. Hopefully that was just me misreading the stick, and not something more ominous. When I topped up the oil again, the ol' slip-n-slide clutch was back. *sigh* So, I spent most of today (having taken the day off after a very theater-intensive weekend) in the garage, playing with the clutch. First thing, lemme give you some vocab, so I don't have to clutter up the rest of this little story. The circular thing in the center of that picture above is the clutch. Friction plate: One of 5 discs in the clutch which is covered in a friction material, something like cork. Also called a friction. Visible as the brown-edged fingers in the picture above. Steel [plate]: One of 5 bare, flat steel discs in the clutch, interleaved between friction plates. Not visible in the picture above, but they're spacing the friction plates apart. Dished steel: The last steel plate on the engine side. It's just like a normal steel, except that it has a slightly concave shape. This allows it to either push the stack out (like in the picture above, note the gap between the last brown friction plate and the back of the clutch basket), or allow it to go closer to the engine. Pressure plate: The outer-most plate of the clutch, it's the big silver plate you can see with the upside-down B marked on it. Ok, so the previous owner did a bunch of stuff with the clutch, he said. He claimed that he installed new friction plates, and new springs. In the condition I got it, none of that was obvious, and today I finally figured out why. It turns out that the friction plates he got are 3.5mm thick. They're supposed to be 3.0mm thick. He must have installed them all, seen them nearly falling out of the clutch (once you take off the pressure plate, the plates are free to fall out), and decided something was wrong (which it was). Only, he must have figured that he installed that dished steel backwards. In its stock configuration, the CL175 clutch has the dished steel installed like in the picture: pushing the stack of plates further out. With the correct thickness friction plates, this results in a stack that's the right height when you have 5 frictions, 4 flat steels, and the one dished steel. Well, he must have figured, that doesn't look right, so the dished steel must go the other way. So he installed the dished steel the other way round, which ends up looking like this: 
If you look toward the outer end (this is the view of the clutch without the pressure plate installed), you can see that there's a bit of a gap between the end of the sliver clutch basket (the thing the friction plate fingers slot into). This stack is too short, and this is the state I found it in. When the stack is too short, the pressure plate doesn't exert enough pressure. It doesn't compress the springs enough. Well, with these extra-thick friction plates, when the dished steel goes the other way, the stack is too tall. This means that, although the pressure plate is now exerting about the right amount of pressure (a bit more than is ideal, but that's better than the other way), it's also so tall that when you pull the clutch lever, the pressure plate hits the cover that normally keeps all this stuff inside the engine. See the first picture, and note the recently-added scuff marks about halfway between the bolts and the outer edge of the plate. Pulling the clutch lever causes that circle in the center of the last picture to push out. This pushes the pressure plate out. This allows a bit of a gap between all the plates, and the clutch is no longer engaged. It only moves a couple of millimeters, but with this too-tall stack, that's enough to scrape metal against metal in a most ungood way. Anyway! The practical upshot of all this is that this bike is grounded until I can get the right friction plates. A racing friend says he's got a stack of stock parts he'll send me, so hopefully I'll see that in the mail in the next few days. Then I can put it all back together and it should just work. Finally. I hope. Posted at 19:28 permanent link category: /motorcycle Fri, 03 Apr 2009I had intended to ride the CL175 to work today, but when I turned it on and hit the starter button, I received a pathetic little click noise, and the electrical system died. I poked at it for a second, but realized that I couldn't deal with it just then. I rode the Ninja 250 in, suddenly thankful that the 175 hadn't pulled this trick far from home and late at night. When I got back tonight, I broke out the multimeter and started checking things. It actually only took about 3 minutes to find the problem: one of the two connections off the battery was heavily corroded, although it looked good from the outside. I cleaned that up, slathered it with dielectric grease, and was good to go. I decided that my first mission, given how reliable the bike had been so far, would be to Sears, to pick up some tools. I picked out a reasonable set of wrenches, a multi-tip screwdriver (bane of anyone who's ever had to turn a screw down a narrow hole, I can tell you right now), and a pair of pliers. I also grabbed a sparkplug socket, but couldn't find a T-handle driver despite stopping at three different stores. I'll either order or make one. First mission accomplished, I realized that I was close to a freeway entrance, and the bike had been working very well. It had a bit of a lag around 7-8k RPM, but picked up again after that. Tuning comes later, though. So I stuck in the ear plugs, strapped on the helmet, and turned my tiny mount toward the freeway. Surprisingly, the little 175 did very well on the freeway. I had no trouble keeping up with traffic, and I realized that my previous diagnosis that the clutch was still slipping was incorrect. That was a nice moment: I could check off "freeway worthy" and "clutch works correctly" at the same time. I rode from Northgate south to 50th, and turned around. On my southward leg, I noticed that I hit something above 80 MPH indicated (I didn't notice the exact peak), although at that speed I was just barely creeping ahead of traffic, so it was probably more like 70 MPH. There was a bit of steam left, but not much. If I'd had more room, I probably could have squeezed another 5 MPH out of it, but that would be absolutely it. This is actually quite encouraging, because I don't think the racebike goes any faster, and it's noticeably lighter, with a fresh top end. I'll have to get the GPS on there, and see if I can get a proper top speed rating. After I got home, I looked at the odometer and was surprised to see that I'd travelled over 20 miles. Of course, the odometer may be just as optimistic as the speedometer is, so it could have been more like 16 or 17 miles. The bike definitely generated some oil-leaking smells, so I've got some tracking down to do. I noticed a bit of oil under the clutch cover, which has a marginal gasket, and most oddly, a tiny puddle of oil on top of the clutch cover, where it had apparently come from under a screw head. That will bear further investigation. However, for all that, it was a very encouraging ride. I got some emergency-stop practice in, so I have a better idea how the bike stops (well enough, but after a relatively fierce initial bite, the brakes don't go much further; definitely not as brakeful as the Ninja). I still need to change the rear tire, but it's acceptable for the task, for the moment. It was nice to finally get a ride on this bike that I've had sitting in the garage for more than a month! Posted at 21:01 permanent link category: /motorcycle Thu, 02 Apr 2009I was preparing to depart for the day a few days ago, and debating my choices. I've been a bit under the weather this week, so I've been motorcycling to work instead of bicycling. The day would be long, including a morning errand, then riding to work, then after work riding up to the theater on Capitol Hill. I looked between my two choices. On the one hand, the Ninja 250, my trusty "modern" bike. On the other, my new-to-me '73 Honda CL175. Eventually, I decided on the Ninja as being the bike I'd rather see sitting out in the rain (the CL didn't have air filters installed, and I didn't want rainwater trickling down into the engine). What was weird was the thought that occurred to me once I had reached this decision: "No, I'd better take the big bike." Ok. The Ninja 250, the girliest of girl's bikes, is now the Big Bike. Let's review, shall we? Peruse with me my wall of bikes. Down there, in the middle of the page. There are ten motorcycles listed.
Yes, when you get right down to it, size really is a matter of perspective. The Ninja 250, a bike which 99.9% of US motorcycle riders would consider a little tiny girl's bike, is now my "big bike." And ya know what? I really like it that way. Posted at 22:43 permanent link category: /motorcycle Categories: all aviation gadgets misc motorcycle theater Written by Ian Johnston. Software is Blosxom. Questions? Please mail me at reaper at obairlann dot net. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
