Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater
Oh. Huh. Yeah, that might be a problem.
I've been trying to track down this lack of power problem with my new/old motorcycle. It feels exactly like it's running out of fuel -- it just kind of runs out of steam, like it's an old man who's done a sprint, but that's all he's got in him.
So I've been tracking down the path of carburetion. It feels like a carburetion problem, like it's running out of gas. Obviously, if you run out of gas, you can't make power. Duh.
To that end, I rebuilt and replaced everything in the carburetion path that I could get my hands on. It's all shiny and new. So I went out last night to check it out, and... yeah, it's exactly the same. What's weird is that it's exactly the same problem. I made all these changes to the carburetion system, and it's still exactly the same?
So I sent a quietly desperate message to the F-160 mailing list last night, detailing my problem. I got some good suggestions back, and started going through them one by one.
The two big ones that I hadn't already tried were to test compression, and check the spark plug caps/wires. Since the compression test would be easier to do, I started with that one.
Test one, on the left cylinder: 110ish PSI. Hmm. Seemed a bit low, but I moved to the other side, since the real test is whether there's a big difference between the cylinders. Hmm. 90ish PSI. That's... well, it's not the 25% danger limit, but 90 PSI seems really low. So I checked the book.
I was just glancing over the Compression Test procedure as outlined. I spied a number, and started reading:
...For example, on the first kick the gauge might indicate 90 psi; teh second kick, 140 psi; the third kick, 160 psi, etc.
Woah. Back up there. 90 PSI on the first kick? Whaaa? Something is clearly wrong here. So I skipped a little, and read:
Normal compression pressure at sea level will be about 140-170 psi, decreasing with altitude.
Oh, hmm. That doesn't sound good. And I'm basically at sea level, so... I guess... Yep, I guess the engine's coming apart.
So, it looks like the CL project is on hold until January. I'm not about to launch into dismantling an engine with the holidays looming as they do.
Ultimately, I can't be too upset about this (and I'm not, just a little disappointed). I knew what I was doing when I bought a 36 year old motorcycle. There was a pretty reasonable chance that I'd need to rebuild the engine, even with low mileage. Fortunately, this engine is pretty simple to rebuild. Good thing I'm not trying to do this with a modern 4 cylinder engine, they're so complex I probably wouldn't try.
Posted at 12:22 permanent link category: /motorcycle
Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater