Topic: oil pressure numbers 77Auto

[salukispeed]

Is anyone running an oil pressure guage mounted in the right plug just above and behind the point cover. My 74 750K4 has fairly steady pressure and acts pretty normal from 20 lbs at idle and 60 at rpm but my 77A is all over the map. even warm it starts around 20 and builds up to close to 90 then snaps down to 60 at high rpm. Is there something I am missing because of the auto trans? I have removed and checked the screen and pan for debris. I wish I never put a guage in it now. Is it likely the relief valve is sticking? I am headed to the garage for the manual after writing this.

[raymond10078]

The oil pump on the A bikes has two rotors - one for the engine, and one for the trans.  Each are independent of the other (except that they are driven off the same shaft).  The engine oil system is pretty much the same as the oil system on the non-auto bikes.  I checked the Service Manual and it shows a  high of 64 pounds the engine oil system - so if you were up to 90 - I'd guess that your relief is doing its job to keep oil pressure down.  My overall point is - the auto portion of the bike can't cause an issue with the engine oil side.

[salukispeed]

I didn't think they were directly related and looked in the book to confirm also.  Just seemed odd that it would spike before settling down  to a more normal number. Thanks for the input.