Saturday, April 23, 2016
A while back, I modified my throttle shaft to allow my carb to open all the way. It worked well, for a while. I noticed that it still wasn't going WOT, so I moved the ball fitting a bit closer to the center line of the throttle shaft. Much better.......until last Saturday. I was riding along and the throttle stuck in the idle position. I jury rigged a fix and was able to finish the ride. Upon getting home, it was evident that the pull on the cable was almost passing across the center of the shaft. No good, at all. I brainstormed it, for a while and decided that I needed something like most bikes have, a circular drum that allows the cable to pull, regardless of the distance from the butterfly shaft. I tossed a hunk of aluminum in the lathe and whipped up this gizmo. It screws to the throttle shaft via a sheet metal strap that I riveted to it. The cable slips in a radial groove on the edge of the drum and is secured in the open hooked hole. After a few tries, it works slick as snot on a brass doorknob. I only had to deepen the groove a tad more to get WOT. The deeper the groove the quicker the action.
Monday, April 11, 2016
I finally rode the bike today. It ran OK, but still not what I was hoping for. I returned to the shop, figuring I would tinker with the timing and carburetor adjustment. First, I decided to clean up a bit. Put tools away, sweep the floor, do some light house keeeping. As I was sweeping the floor, I noticed a small object being pushed into the dustpan. Further investigation showed it to be the contact button from my distributor cap. The spark had been jumping 1/2 inch, from the coil to the rotor, instead of traveling through the contact. Not good. I yanked the cap off and put the button back where it belongs. The bike fired right up and ran so much better. The idle was better. I reset the timing and all seems well, at this point. I'm so glad that I noticed that button, as I was cleaning up. I would have chased my tail forever, trying to figure out the problem
Thursday, April 7, 2016
I finally got all of my ducks in a row and fired up the bike. I only ran it for 30-40 seconds. The pump seems to work well now. I was surprised to see the amount of gas that flowed from the idle bleed line. I had it running into a can and it pumped a quart, or so, into it. I thought it was no big deal, and I'm sure it is normal. Normal for a standard installation, that is. As we know, this is far from normal. I soon realized that there was a big problem. Let's back up a few years. When I added the pump, I also added a three way valve. On, off and reserve. It has worked flawlessly. When I run out in thee main tank, I would reach down and switch to reserve. Easy Peasy. Now it is very evident that this will not work anymore. Why, you may ask. The culprit is the idle bleed line. When I switch to reserve, the pump will draw from the reserve tank as it always did. However, and this is a big however, the idle bleed line will still flow the excess gasoline into the main tank. I estimate this will take 2 or three minutes and then my reserve tank will be sucked dry. Now, I could then, switch back to the main tank but this seems ponderous and Mickey Mouse. So, what I did was re engineer the fuel lines. The three way valve went into the parts stash. I ran a line from the main tank to the fuel pump suction side. I teed into that line and ran another hose from the tee to the reserve tank. In between the tee and the reserve tank, I installed a small, electric fuel pump and an electric shut off valve. When I run out of gas, I just flip a switch, the valve opens and the fuel from the reserve tank is pumped into the main tank. After 5 minutes, or so, I can switch it off. That's it. Nothing else to do but to look for a gas station.
Friday, April 1, 2016
Some would call it a comedy of errors. I prefer tragedy. I seems all of my, carefully diagnosed problems were misdiagnosed. I did not need a new cam. I did not need a new fuel pump push rod. So far, it would appear that it was, after all, a fuel pump failure. I sent off for a kit to rebuild it. I contacted the manufacturer and the inventor of the pump. He said I need to run an idle bleed line. This is a line that runs from the regulator to the tank. A return line. My tank has just one fitting, the outlet. He told me it has to be plumbed so that the gas enters the top of the tank. Fine for a car, bad for a bike. I thought about running a tube up through the bottom of the tank that almost touched the inside, top of the tank. I later felt that it would be awkward to get at and would negate the quick release tank setup that I showed in an earlier post. I finally thought, why not just drill a hole in the top of the tank and solder in a bung to accept the return line. It would be right there in front of God and everyone else to see. Sort of a form follows function, industrial, racer tech look. Here is how it turned out. of course, the paint suffered, but it's acrylic lacquer so it's an easy fix. I drilled another hole in the top of the neck and ran the hose through it and down to the regulator, which is just at the juncture of the neck and the front down tubes. I also fabbed up a little plate to hold a rubber grommet to keep the hose from chafing. I like the look. no nonsense and purposeful.