Engine noise problem, Oli light always ON, Jet needle size, for 1973 z1

Hi I just finished restoring my 1973 z1 and found a few problems. The first problem is that the oil presure light is always on and I don't know why the bike fires up and rides ok; I rode it around the block and it does need to be tooned some more.
My other question is I have an engine noise when the bike idles in the low rpm; but when pull in the clutch lever the noise goes away, the noise also goes away anytime the rpm gets higher than 1100rpms.
And my final question is does any one know what is the correct size needle for the carburetor: the caburetor is a 28mm original to the 1973 z1. I'm concerned about the needle size because the previous owner had pod filter on the bike and might of changed it.

Thanks you for any extra help. Thanks

There is a guy called wiredgeorge who can answer any carb related questions he also has a site www.wgcarb.com

Here is FSM info on the carbs.

28mm (VM28SC) Z1 & early Z1-A
Main Jet 112.5
Air Jet 1.0
Needle Jet P-8
Jet Needle 5J9-3 - last number is the clip position where 1 is at the top of the needle (leanest) and 5 is at the bottom (richest)
Throttle valve (slide) 2.5mm cutaway
Pilot Jet 20.0
Air Screw setting 1 1/2 turns out

thanks for the carb info. I still need to figure out why my oil light is always on; can I somehow check why the light is always on? I also realy need to know what that engine noise can be. It sounds like a chain rattle in the bottom of the engine; and it only rattles when its at low idle, but as soon as you pull in the clutch the noise goes away, it seems like it has something to do with the clutch or transmission but I could be totaly wrong. Can any one help would love to ride my restored project but now I'm stuck. Thanks

So you restored the bike COOOL. What did you do to the motor in this restoration
project?
Is it a stock motor?
How many miles on the motor?
Did you have the motor apart or someone else have it apart?
Way to many options at this time. We need more info.
If nothing else pull the valve cover and check the cam chain and guides.
Make sure the clutch is adjusted correctly at the push rod. Make sure the rod
has not welded it self to the the ball at the end of the push rod.
The list can go on for ever.

XENU

Its a stock motor and I completly rebuilt it. New pistons, cylinder sleves and just about everything else is new and rebuilt on the motor. The only think that was not rebuilt is the transmission and the crank shaft because I didn't split the bottom block to do so; I thought it should be in good shape. I double checked the cam chain and its nice and tight it was slaping at first and than I solved that problem. And I don't think the cam chain or anything in engine such as guides, valves and pistons are a problem; I don't think any of this can be a problem because the rattle noise goes away when I push in the clutch and the rmps don't change when I push in the clutch. So I think that I will have to check the things you mentioned FastKaw1. Can you explain more on the proper clutch adjustment and the push rod being welded shut. I also thought that the rattle noise might be do to clutch noies or old springs in the clutch plates, That is one thing I did not changed, I used the old clutch and the old clutch springs. The bike was sitting for a long time before the rebuilt and I had to unfreez the clutch plates. I don't know why I changed everything on the bike but neglected the clutch. But who knows if thats the problem. But any help would be apreciated. I will also post some pictures; the bike sweet I just need to get it running perfect after all this work. Thanks for any input.

You should check your oil pressure, i believe that spec is 2.8 psi at 3000rpms.
If you remove the plug on the main oil gallery ( right side of the engine), you can drill it and tap it for 1/8 pipe thread and use a 0-15psi gauge ( usually sold as a fuel pressure gauge for car)
Also remove your oil pressure switch to make sure that it is working correctly (or not)

You might want to drop your pan cover to see what might have collected on the bottom. It would also be a good time to check the oil pump (I just recently done myself), you might be surprised to see what is down there. I found a broken shim, a piston ring clip, and what appears to be mud (oil & water) from the previous owner. I rebuilt my top end, but didn't check the bottom end. It might be worth it to do, spent $10 on the gasket and about 2 hours to do.

Royal1MC wrote:

You might want to drop your pan cover to see what might have collected on the bottom. It would also be a good time to check the oil pump (I just recently done myself), you might be surprised to see what is down there. I found a broken shim, a piston ring clip, and what appears to be mud (oil & water) from the previous owner. I rebuilt my top end, but didn't check the bottom end. It might be worth it to do, spent $10 on the gasket and about 2 hours to do.

Good suggestion on dropping the pan and cleaning it out along with cleaning the oil pump screen.I might add that while youre inside it,with the screen off the oil pump,bevel or radius the oil intake port of the pump,helps flow a little better.Open the oil pump up and make sure there are no scratches on the walls where the rotor gears turn,if so use a dremel tool or something similar and polish the walls smooth again.The outside flat plate of the oil pump can be "milled" down just a very little bit to tighten the pump up.Also where the pump mounts,make sure you get a new rubber V edge O-ring.
And on the oil filter bolt, make sure you have the flat washer on top of the spring,just under the oil filter,dont use a high flow expensive filter either like K&N,etc.,..they reduce the effective oil pressure,And these bikes dont have any extra to spare.

Need to check the nut on the clutch basket to make sure it is tight. They will make a similiar noise if they are starting to loosen up.

Ok thanks for all that info; I did drop the oil pan during the restoration and I cleande it up really good and yes I was suprised at what I found in the oil pan such as the timing chain guide all bent up, but there was already an other guide installed on the bike but the previous owner must of never cleand out the guide; Who know what happend to that guide while back. But when I pulled the pan I did not check the oil pump, this wont be a bother because I do have a small leak on my new oil pan gasket so I was going to drop the oil pan anyways so I will check for anything that could reduce oil presure but most importantly the stupid rattle noise. I will also check the oil presure with my new tool. And I will replace the clutch basket and make sure all the bolts are tight on the basket. So thanks for all that info I will give an update when I check all the suggested problems. Thanks