My Commuter

I have a Honda Nighthawk (CB250) as my daily driver. It is the only vehicle I own that does not have "Historic" tags. I read it would get 70MPG on average., though on the Yahoo Nighthawk group, some guy in GB said he got 90MPG highway, I didn't believe him.


When I drive it, I have fun. Because the engine is so small (Two cylinder 250cc, you know, 0.25 Liters) , I really feel no guilt in just pouring on the throttle. I'd been driving it hard, always topping out gears before shifting, especially to stay away from people driving cars. When I checked at the pump I was getting 50MPG.

After seeing that, I decided to drive conservatively just to see the MPG I could get. I was not driving super conservative, I was just driving like a car, accelerating calmly, turning the engine off at long lights, and still speeding up quickly to avoid people crazy enough to be driving cars.

I checked again at the pump . . . 200 miles . . . 2 gallons of gas . . .

Yay four stroke engines~!

RX-7 Convertible Headrest Modification

All RX-7 convertibles, came with headrests speakers, two to each headrest, with volume controls for the passenger and the driver. I've heard other cars, such as the Miata, also came with these. After upgrading the audio equipment everywhere else, I noticed that the sound from these headrest speakers is pretty bad. The crapiness of the speakers was especially potent because they were right next to my head, and that's not really acceptable.

After disassembling the headrest, you'll get to see this weird oval/rectangle speaker


Yeah, pretty sad. Compare it with these Infinity Reference 3002CF speakers in the picture below. I picked these 3.5" speakers because I liked the high and mid-high range sound. Headrest speakers only need to carry that range, as the lows are for your larger speakers behind you or in the doors.


Here the speakers are side by side so that you can see and compare the backs.


Since I'm not a hardcore audiophile like Dan is, I decided to re-use the stock speaker mounts instead of fabricating a custom box. They are made out of a rather thick hard plastic, and that's a good thing. However, they are prone to cracking because of the way they are fastened to the headrest, and of course their age. Make sure you have some superglue handy.


Here it is! Modded next to un-modded. Make sure the box does not touch the cone of the speaker at any range of its movement.


Here is a picture of the modified unit dissasembled in front of the headrest mounting bracket.



Here you go! All done! You don't need to put Dynamat on the headrest, I just put it there as a joke for Trevor. It's a really thick piece of metal already.

Final results: the sound is awesome! It does not take over the super highs (as those are handled by separate tweeters in front of me) but it handles the high and high middle very well. It's really fantastic for when the top is down and it's really noisy outside, I can still have my music coming in nice and clear.

The Magic is Gone

Picture I took outside of Mustang Magic, after the wall fell.
For the story, click here.

(Click for a larger image)

Tofuball's Reading

I removed all the unrelated stories from the site, because, well, they were unrelated. I moved them over to Tofuball's Reading.

ReadingTofu.Blogspot.Com

How not to remove a tree.

My friend Theo from RX-7Club had a tree problem; in the back of his yard, looming over his tool shed, a dead tree was about to fall on his house. The tree was about about a foot and a half in diameter.

To keep it from falling and breaking things, he wrapped a logging chain around the trunk and used a come-a-long to secure it to a larger tree nearby.


He asked the forum what he should do next:

I have already cut a small wedge out of the tree in the direction of the come-a-long... But not enough to get the tree leaning that way. Once it does start leaning or falling, it'll release the tension on the chain/cable... Then it won't pull anymore. How do I pull it down when the tension is off the cable?

Any other bright ideas before I go killing or breaking something?

He then went out and notched the tree in the direction of the shed:


And the next time he posted, we were graced with the following pictures:



Luckily the shed was crappy and he didn't care much, and the gutters aren't THAT bad ;)

You can read the thread for all the details, and the nom nom shedz tree, here.

Installing a Reinforced Ceiling Electrical Box Gone Wrong.

Hey everyone, Dan here from the MoCo Eats blog. I don’t know if Tofuball has ever had this problem before, but I have personally found that sometimes your home improvement projects just don’t want to go exactly as planned. From the experience I had last night you might never want to take my advice on any how-to projects again, but trust me when I say this is NOT normal for me.

The mission was simple: install a reinforced ceiling fan electrical box in my bedroom ceiling, run a wire to it, and then connect that wire to a wall switch. Sounds simple right? Well as I’m about to explain, the "simple" tasks aren’t always as easy as they should be.

The Planning Process…

My entire attic is filled with blown-in fiberglass insulation so I knew I would have to suit-up as much as possible to avoid itching for the rest of my life. My brilliant idea was to purchase a full body tyvek suit which would keep the fiberglass off my skin, and it worked great . . . Except it also kept out air and kept IN sweat! If you've ever been in an attic in the middle of summer, you know how terrible that is! So, picture this, I am suited up like a HAZMAT cleanup worker, crawling army style through a tiny little opening in the mounds of fiberglass. At this point I realized that the beams there were only 8 inches apart and the reinforced ceiling box is 16 inches wide. Unfortunately the brace has to span across the beams so it can hold the maximum amount of weight, but since the beams are so close together this setup is now impossible. I retreat for now, I must come up with a new attack plan.

Once I reach the temperatures downstairs I tend to take my time planning my next strategy because the attic is so hot. Yesterday it was hovering around 90 degrees, but last week I put a thermometer up there and it read 113.4 degrees. So bottom line, if you want to lose weight this is a PERFECT opportunity! Put on that Tyvek suit and get to work. After a few short minutes you’ve magically lost 10 lbs!

At this point I have confirmed that the electrical box I have won’t work, so I have to find an alternative. I could put a wooden brace above that one and nail it into the beams, but that would involve two trips into the attic, climb up to measure, come down to cut, and return to nail it in place. That alone was reason enough to rule it out. So my idea was to find a box that has a metal brace on the side that can be screwed into the stud on one side only. I don’t recommend this method to anyone else as it’s not quite as strong as the full length braced box. But for my particular situation it should suffice.

The Installation…

So I climbed into the attic and held the box in place long enough to trace it with a pencil. Then I moved the box out of the way and cut the hole with a drywall saw. All I had to do after that was put the box in place, call for my lovely wife to help me get the height right so it’s flush with the drywall, and drive in the screws. After yelling for several minutes I realized she was in the basement and so I just waited patiently as 5lbs magically burned from my body. Eventually she came and I was able to get everything fastened properly and get the heck out of that part of the attic permanently!

Installing the Wire in the Wall…

All I have to do now to finish the job is run the wire down the wall and hook it into the switchbox. This part is super easy, just drill the hole, drop the wire and pull it into the box. Well not so fast, this too can be complicated! I measured the distance from the walls so I could drill in the right place and I marked the location. Have you ever started drilling into an enclosed wall when suddenly light appears through the very hole you’re drilling? Well I have! The distance from the trim to the wall is different in the attic and my measurements were about one inch off. So lucky me, I drilled right into the bathroom ceiling. True this is easily fixed with a bit of drywall mud, but the hole just so happened to be directly above my wife’s and my own brand new toothbrushes. Literally we had used them twice.

The Final Hookup…

Finally with my wife’s help we were able to get the wire into the electrical box and are ready to do the final hookup and install the fan. I wasn’t able to get that done last night, but I’m sure hoping the next parts of the install will be easier than the last. As a final kick in the gut, when I went to put the screw back in the switchbox I made the unfortunate realization that I had left my best screwdriver somewhere in the depths of the second attic… maybe someone else will find it in 50 years or so.

How does a PCV valve work? What is it?

More then once I've had people ask me "Why do I even need a PCV valve? Can't I just cap it off?" Unlike most other things that are classified as "Emissions Controls Devices," the PCV valve is not useless. PCV stands for "Positive Crankcase Ventilation." What in the world does that mean? To get to the bottom of this, first we'll have to go over some basics:

You should vent the crankcase: We all know about the top of the pistons going through the 4 stroke cycle, but some of us forget about what is going on under the piston, in the crankcase. The crankcase is basically the entire "bottom half" of your engine, containing, you guessed it, the crank. Under the crank is usually a sea of oil, and above that, oil is being squirted or secreted out of many different holes and openings. As each piston drops, the pressure increases, and as each piston rises, the pressure decreases. If you pressurized the crankcase, the pistons would have to fight the pressure to move, so you have to vent the crankcase.

Ok, just cut a hole in the valve cover and put in a filter, that’s your vent, right? Well, it would work for that purpose, however, there are still two more concerns:

Blowby, and her ugly friend, Emissions: Because the seal of the piston rings is not perfect, during combustion, some of the unexploded or even burnt intake charge gets into the crankcase. This is called "blowby" and it gets worse as the car ages and the piston rings wear down. Blowby is a problem because it is acidic, possibly corrosive and explosive. You wouldn't want those gasses igniting outside the combustion chamber, would you? The water vapor in blowby gasses can condense when you turn off the car and cause rust. If left alone, blowby can cause viscosity breakdown (thinning) of your oil, and to top it off, these unburned hydrocarbons are bad for the environment. So you shouldn't just stick a vacuum on your crankcase and suck everything out into the atmosphere. Besides, there is a cheaper solution then going out and buying a vacuum; because your engine's intake is already a vacuum!

So what the manufacturers did is they put a hole in one side of the crankcase and connected it to your air filter, so that it can take in fresh air. This is usually called a "Crankcase breather." On a "V" engine this is usually done on one valve cover, and then the other valve cover is connected to your intake manifold. That way, when you're driving, the engine will suck up all the hydrocarbons and burn them, and keep your crankcase under a vacuum.

Sounds great, right? "But Jason," I hear you saying "It's called a PCV valve, why is there a valve there?" "Silence!" I'll yell, because you're interrupting me, you jerk.

So why use a valve? Your engine vacuum is not a constant. At idle, and at low engine loads and cruising, your engine produces lots of vacuum. However, at more aggressive driving (You know, like in DC?) the engine vacuum is much lower. To keep the vacuum in the crankcase high, they put a valve in that closes at low engine vacuum.

Another reason for the valve: inside the crankcase, oil is flying all over the place creating a mist, or just a splashing such a way that can get sucked into the engine through the PCV. That's mostly OK, as the engine can happily burn such a small amount of oil. However, it needs to be quite hot to burn the oil, and lean fuel mixtures from cruising are a lot more "oil burning friendly" then colder, rich fuel mixtures from hard driving.

Back in the 60s and earlier, cars used to just be equipped with a draft tube, which would just come straight out of the crankcase and out into the atmosphere. The "road draft tube" would use the air passing by to induce a vacuum. It would also randomly dump oil on the road, and just vent unburned hydrocarbons.

Some companies claim to have special PCV valves that make your car get 30% more fuel economy and the like, and like fuel line magnets, you should just ignore those.

A lot of people put "Oil Catchcans" on their PCV line, to catch the oil coming out before it gets into the engine. This keeps the inside of your intake manifold cleaner, and is a matter of personal preference for most vehicles. You can either make one yourself or just buy one pre-made online.

If your PCV valve goes bad, it will either fail "open" and always lets everything through, and that can lead to problems like oil-fouled spark plugs. The PCV can also fail closed, causing problems such as oil coming out your breather tube and soiling your air filter. If your system doesn't incorporate a breather tube, or it's clogged, your dipstick may pop off from the pressure, and your engine will run a little worse, possibly burning more oil.