Engine still knocking after valve adjustment

[jpdoom]

I recently acquired a 1980 xs400g special II that wasn't running. I pulled the carbs and gave them a thorough cleansing. After reassembling, it worked! There was a loud knocking coming from mainly the right side of the engine. I adjusted the valves and it still knocked the same, so I did it again. This time, I found both the adjusters on the right side were stripped. Ordered new ones and put them in. STILL KNOCKS, more so on the right side still. I've read the problem could be the cam chain. Is this true? What could the problem be?

Thanks in advance.

 

[jmd_forest]

Could be a valve tap, could be a main rod bearing, could be a wrist pin, could be a wiped cam.

 

[jpdoom]

Thanks for the reply. I'm new to working on bikes but have experience in classic cars. Could you explain how I might be able to pinpoint any of these issues?

 

[jmd_forest]

Valve tap should go away after adjusting valves. wiped cam through visual inspection of cam lobes during valve adjustment. rod bearings and wrist pin only through engine teardown.

 

[xschris]

When you adjust the valves instead of using the fly wheel to find tdc look in the spark plug hole And watch the piston go to the top. My 80 on the left side was off from the flywheel quite a bit and when I set the valves using the mark it made a lot of lifter noise. Its weird but it worked for me and after 800 miles still works fine

 

[frwinks]

check for leaks around the exhaust gaskets. I had a valve like tick as well, replaced the gaskets and the tick is now gone

 

[jpdoom]

Thanks for the responses! I will certainly give these a try before going to extremes. I did however already remove the cylinder head and noticed that the reservoir under the cam lobes on the right side of the engine was not as full as the left. The cam lobes however were not dry. Nice and oily. Could this be a problem or could it just be from shifting the bike around?

 

[jpdoom]

Tried both suggestions and still getting the same, distinct, LOUD knock!! I'm thinking it is probably the valve seat because it definitely has a divot in it. Yes? No? If so, any tips or advice on how it's done? Thanks for all the help!

 

[drewpy]

knocking is usually mains bearings, loud tapping is small ends

bag of nails is valves/rockers

 

[jakefromstatefarm]

@drewpy
what do you mean by small ends?

 

[drewpy]

@drewpy
what do you mean by small ends?

where the conrod meets the pistons