Yes, I have two cases. One is a replacement case where the dealer stamped the number on the engine. The other one is a factory stamped engine number and I have many of the engine parts that came inside. It was left outside for years when I bought it but most of the parts can be cleaned and...
I just finished restoring a 1971 CB750 and had sputtering when I gave it full throttle. I removed the air cleaner to troubleshoot and the problem did not occur. So that told me it was running too rich at full throttle. At full throttle, the main jet is the one to change, so I went from a 120...
I would suspect it is running too lean if it sputters when you back off the throttle. One way to help diagnose it is to remove the air cleaner and take it for a ride. If the problem gets worse or stays about the same, it is too lean.
Here is a 1971 CB750 K1 project that I just completed. I took everything apart and fixed/restored it. I did all the work myself including the paint. You can see some GL1000 parts that I painted along with the CB750 parts. The bike was in bad shape and had been sitting since 1983.
When you remove the oil fill cap, do you hear and feel air pressure? Maybe the cap is not venting properly? Also, did you install the small oil orifices which limit the oil to the head?
These are shown in the parts diagram #6.
Partzilla Parts Diagram
I think you will be fine with this case. You may have to reweld it, but after you clean up the weld joints, it will be fine. There are many on the road that have been repaired.
I am looking for a K0 frame. If you have one or know someone that might have one, please let me know. I came across a 1970 K0 engine case that had been stored for 35 years and need a frame to go with it. Thanks, Cedric
Prior to adjust the timing chain, first set the timing mark to the "T". Then loosen the adjuster bolt. If you press on the adjuster shaft with a short screwdriver through the rear shaft hole, you will be able to tell if the shaft is applying tension to the chain. Without the screwdriver...