I took the time to start performing some work on the CB160 65 Revive project. The plan right from the beginning was to first address the power train aspect of the project. Since the bike was purchased with a blown up engine it was important to establish whether or not the engine could be saved and therefore continue on with the remaining components of the bike. When I bought the bike a spare engine, of unknown condition, was included. The spare engine had external signs of issues most notably being the broken cooling fins on the cylinder head.
So I started by first tearing down the spare engine and laying out all the parts. Next the original blown up engine was removed from the bike and it too was torn down. Once I had every single component from both engines disassembled and laid out I was able to start performing a thorough inspection to determine what I was dealing with.
Well it turned out that there was a significant amount of damage found in both engines. Both the original engine case and the spare engine case had holes in them. Transmission teeth were broken, piston ring lands broken, clutch rods bent, cases welded, plus multiple other issues. So I am turning this post into a picture post with captions. I took pictures of the significant issues and documented them. I have yet to clean everything up and do a final inspection however at this point, even with the known damage, I am feeling good about being able to save the power plant. It’ll take some time to source parts however I think the challenge is realistic. So you can join me below in observing the reality of what I am forced to face.
This is just one of the benches that the engine was laid out on. The parts viewed heare are all from the spare engine. The second bench was comprise of a couple of saw horses and and an old door that is suspended overtop of the bike in the middle of the shop.
The spare engine had multiple welds on it. Based on the condition of other external components I suspect this engine was involved in an accident. This particular weld was on the bottom side of the lower case. The mount that is shown is for the foot pegs.
These are the cylinders off the origianl engine. Obvious damage is visible and the barrels have been completely destroyed.
This is the cylinder head off the spare engine. The internals of the head are in decent condition however many of the cooling fins have been broken. So as far as the casting goes it is garbage however some of the internals may be salvaged.
This is the upper case half of the original engine. The case got a hole punched through it when the engine blew up.
The rocker arms of the original engine had lots of wear on them. The picture does not illustrate this very well however all 4 arms are good for scrap metal now.
Second gear on the countershaft of the spare engine had a tooth missing. I found the “loose tooth” in the bottom of the case.
I was really hoping the pistons in the spare engine were going to be good. No luck. One of the pistons had broken ring lands. The donor engine had already been bored out 2 sizes over as it had .50 pistons in it.
The valve cover/upper engine mount of the donor engine was repaired with a substance similiar to JB Weld. Although the picture doesn’t show it the underside of the cover has a clearly visible break in it. More eveidence that this engine was involved in an unfortunate incident.
Major cam lobe wear in the original engine. The wear matches all the wear on the rocker arms.
This is the clutch actuation rod from the donor engine. It was clearly bent. I am unsure exactly how something like this would happen, it is possible that the damage may be related to an accident.
Here is the crankshaft, rod, and piston assembly out of the original engine. There were no sign of a piston when the cylinder head and barrels were removed. The nub of the broken rod is what punched through the upper engine case and cylinder. Based on the cam wear and the broken rod I am suspecting the engine may have suffered from oil starvation.
This is what remains of the pstion, wrist pin, and oil seperators from the original engine. This was all collected out of the bottom of the engine case after it made its way through the transmission.
This is the bottom half of the engine case from the donor engine. There was a hole punched throught the bottom. Based on the break it was obvious that it was a result of external damage. That makes for 2 bad engine cases.