After work tonight, I started playing in the garage. I had several small fixes in mind for Salty, but didn't think I would be trying to get him up and running. Somehow, things just came together, and the end result is a running engine!
Fix number one was to modify the center stand return spring plate. When I built the rear brake arm, I apparently fit everything with the bike sitting up on its center stand. Unfortunately, when I lowered it down on both wheels, the little "C" shaped bracket that attaches to the frame and the return spring interfered against the brake arm. A little grinding, drilling a new upper locating hole, and some fiddling, and I got everything to work together.
Then I installed the spark plug and fit a kick start lever from some random bike with just enough "curve" in its shape to clear the exhaust. After that, I decided to put a small amount of fuel in the tank to see if the rebuilt petcock I had mounted worked and held fuel. After a few minutes of no drips, I then decided to fill the crankcase with oil.
I gave it a few slow kicks to get the oil circulated and noticed a few small leaks around the "passenger" side case. Then it hit me, that I never made a gasket for that side case. I had simply fit it on loosely when mocking up the exhaust. It didn't leak bad, but had enough drips to where I'll need to pull it off and make a gasket. Or I'll just use some gasket sealer snot.
So, I had a carb getting fuel, a spark plug getting spark, and a bottom end with oil. Well hot damn, I guess I better take it outside and see if it starts.
As a reminder, the engine in Salty right now is sort of a Frankenstein. It is an old ass Cub 50 bottom end, with the 3-speed auto clutch. And by old ass, I mean it came out of a parts bike and had a thick oozy goop coating the insides. I "washed" out the innards and soaked it in the solvent tank for a few days at work. It turns over, but other than that, I have no idea how the bearings and trans looks.
Then I mounted fresh top ends parts, which are the main hot rod items on the motor. In this case, I'm using one of the two freshly honed standard bore cylinders that I had 0.040" milled off the top of the barrel. Combined with the ported C110 aluminum cylinder head that has a matching 0.040" milled off the bottom mating surface, that raises the compression from 9:1 to around 12:1. I also fit stock sized lightened valves, lightened rocker arms, and used, but nicely cleaned up stock piston with new rings. Like I said, a Frankenstein engine I figured would be perfect for just using to mount up in the chassis and build stuff around. If it wants to actually run, then that would be cool too. So my expectations were pretty low at this point.
A big part of getting Salty up to record speeds will be the gearing. Last year, I spent a lot of time making a spreadsheet to determine speed in gear for both the C100 3-speed trans and C110 4-speed trans. I've long since forgotten the outcome, but I think both the 3-spd and 4-spd have similar top gears ratios, so if I could get up to speed using the semi-auto 3-spd, then I didn't have to worry about mounting up and building a clutch cable.
So, short story made super long, Salty runs. It took a while to kick over because I realized my throttle cable adjustment was too "tight" so the throttle barrel was lifted a little in the carb. Essentially, it was as if I was holding open the throttle. After solving that, I gave it a little choke and it fired right up, and revved to about 90,000rpm. It was probably only 4,000rpm, but god damn was it loud! I fiddled with the choke a little, and adjusted the idle screw until it sort of settled down. It wasn't running real great, and wouldn't hold an idle, so it eventually died.
Then a few minutes later Susan got home, so I started it up for her. And of course it ran better, so I assume a little bit of heat and a few more adjustments to the idle and mixture screw, and it almost settled into a normal idle. It even revved fairly clean through its range a few times.
I immediately grabbed the oil drain pan and pulled the drain plug to drop the oil, since I'll need to seal up that out case cover. And of course Susan got a photo of my triumphant moment:
It still isn't quite road worthy yet. Obviously I need to fix the leaky side cover, put oil back in it, get it to run a bit better and hold an idle. Besides that, I need to fit a chain, do a full nut and bolt job on the entire bike to make sure nothing rattles off, and then do it again to make sure i haven't forgotten anything. Maybe this weekend I'll get to ride him down the street.
C'
