Looking for advice from those who have done it before...
Bought the bike for a project. The Electrical forum here helped me to get proper spark (thanks, guys), but the use of transparent fuel lines proved I wasn't getting enough fuel during cranking, and what there was of it was filthy. Carbs are off and I'm rebuilding them. One at a time they are being disassembled, spending 12 hours+ in a Gunk carb cleaner bucket, brushed with a toothbrush where I can reach, rinsed in warm water, and blown out with compressed air through every orifice I can find.
Question: Is it worth it to get an ultrasonic cleaner? Some videos I've seen of before and after show they don't look any better than what I got with the dip, which doesn't give me a ton of confidence they are superior in cleaning out the insides any better. I know I also have to watch what I use for a cleaning agent, since some can attack the aluminum. It looks like I'll have to spend $150-$200 for a cleaner with a heater and some cleaning agent. Would I have a use for it beyond the carbs? Beyond the bike? I'd need to justify the cost to the wifey...
Also: while trying to get it to start, I performed compression and leak down tests. For compression, cylinders 1-4 read: 145, 120, 140, and barely over 30psi. So #4 is a dead cylinder.
On the leak down test, I didn't exactly have the motor at TDC. I just rotated it until the pressure in the cylinder started to increase. I would rotate through the cycle a couple of times to try to get accurate/consistent readings. This might not be the superior way of doing it, since I think my loss percentage readings were a little wonky in relation to my compression test results. Cylinder 1, which had the best compression, leaked the most at 65%, mostly through the exhaust. 2 was at 45%, mostly through the rings. 3 was 35%, mostly through the rings. And 4 was at 60%, mostly through the exhaust. So, while I'm sure there's carbon on those exhaust valves, I'm pretty sure those cylinders need attention, too. The odometer reads 28,300. I'll bet that's at least 128,300.
Question: Once I get the carbs as put together/functioning as best I can on the bench, should I put them aside and then go straight to a top-end rebuild? That's where I think I'm headed. Everything needs attention, I'm just trying to only do a little at a time so I don't create a parts farm.
Thanks,
Chris