No oil pressure.

[cliff7]

On the 400 the light would be off if there was a bad connection, the same on the 500/550, surely. Disconnect wire and see.

[Johnny4428]

Thanks for all help and comments, had to leave it tonight. Will check connection tomorrow.

[SteveW]

Just worth mentioning. If for any reason you need to remove oil pump you can do it without draining the oil.
Just lean the bike right over against a tree on a lump of foam.

Thats  how I changed the O rings in my pump, lost about a teaspoon full.

[McCabe-Thiele (Ted)]

Just a long shot - is there an oil pressure relief valve on a bike engine as per a car engine ?
A stuck relief valve can cause similar issues on cars.
I had a very similar problem with a Nissan 2.7 engine after an oil change - turned out to be the new oil filter none return valve was faulty. New oil filter fixed it.

[Bryanj]

Relief valve is part of oil pump.
To check if pump is working remove a cam cover end cap and loosen the bolt holding the steel bracket, oil should flood out

[Johnny4428]

She,s back with a little intervention! Disconnected wire to oil pressure switch this morning and light goes out. So decided to remove oil pressure switch and prime pump with oil, popped pressure switch back in and connected wire fired up bike and within seconds oil pressure light went out. Checked oil level gone down to just above lower mark now I’ll be able to put rest of oil in. Shouldn’t have to prime pump but if that’s what it takes that’s what I’ll do. Any thoughts?

[McCabe-Thiele (Ted)]

She,s back with a little intervention! Disconnected wire to oil pressure switch this morning and light goes out. So decided to remove oil pressure switch and prime pump with oil, popped pressure switch back in and connected wire fired up bike and within seconds oil pressure light went out. Checked oil level gone down to just above lower mark now I’ll be able to put rest of oil in. Shouldn’t have to prime pump but if that’s what it takes that’s what I’ll do. Any thoughts?

As the sump was not up to level maybee just not enough of a head of static oil pressure to fill oil pump ?
Is oil pick up pipe if there is one  where it should be to prime the pump sufficiently, poor seal between pick up pipe & pump ?

[Johnny4428]

Actually the sump had the correct level,it was up to the top mark on dipstick, but I did toy with the idea of just putting the correct amount of oil in to give a slightly bigger pressure to the pump. Didn’t want to overfill. I think the difference would be very little. I would like to try an oil pressure gauge on it to see how the pump is performing.

[McCabe-Thiele (Ted)]

Was the oil filter faulty the none return valve in cheaper car filters can be an issue especially none OEM ones.
I'm trying to think outside the box.

[Johnny4428]

I did wonder about filter and in particular the check valve, but I just emptied oil and didn’t replace filter.

[Bryanj]

Filter dont have check valve, there is a pressure relief or bypass in the bolt. Pickup is at bottom of sump.
Never had to bleed a 500/550oil pump ever, even after rebuild

[Johnny4428]

Thanks Bryanj, was thinking of that center filter bolt. I am stumped why I had to prime the pump. Might need to pull the sump off and check  to make sure oil intake has the short hose connected properly.

[Bryanj]

Small pipe would only affect transmission pump as  lower end would be below oil

[Johnny4428]

Thanks Bryanj! Running out of ideas as to why my pump didn’t self prime. When I squirted oil into pressure switch port I certainly got three glugs of air out which I was happy to see. It’s fine now a good kick is enough to activate pressure switch. Good for another 1000 - 1500 miles.