Doctor Jones
Been Around the Block
Hi. Just posting this because it nearly caught us out during the re-build:
When rebuilding the head we noticed that the right hand oil way was open but the left appeared to be closed. Investigating the left we found that it has what Honda call an 'oil control orifice'. It looks like a small socket cap screw. This is basically a reducer that has 4 tiny holes in the shaft feeding a single outlet jet that exits into the camshaft post and is sealed with a rubber 'o' ring. Where the right hand side went, we have no idea but perhaps it was lost in the shot blast process? Anyway, the LH was blocked solid and stopped any fluid transfer whilst the RH was too open providing too much and perhaps causing starvation elsewhere in the bottom end.
Happy ending: One of you lovely American dudes has come to the rescue and is sending us that part. It's not produced anymore and appears to be rarer that rocking horse s**t! So, if your doing this on a CB SOHC make sure all is well, take them out (they simply pull with pliers) and keep those little babies in a safe place.
Hope this helps someone in the future.
When rebuilding the head we noticed that the right hand oil way was open but the left appeared to be closed. Investigating the left we found that it has what Honda call an 'oil control orifice'. It looks like a small socket cap screw. This is basically a reducer that has 4 tiny holes in the shaft feeding a single outlet jet that exits into the camshaft post and is sealed with a rubber 'o' ring. Where the right hand side went, we have no idea but perhaps it was lost in the shot blast process? Anyway, the LH was blocked solid and stopped any fluid transfer whilst the RH was too open providing too much and perhaps causing starvation elsewhere in the bottom end.
Happy ending: One of you lovely American dudes has come to the rescue and is sending us that part. It's not produced anymore and appears to be rarer that rocking horse s**t! So, if your doing this on a CB SOHC make sure all is well, take them out (they simply pull with pliers) and keep those little babies in a safe place.
Hope this helps someone in the future.
