Camshaft Top End Rattle

[Nessism]

ED: As you will have now realised I have fitted the valves back into the cylinder head, so am not keen to pull them all out again to check if the contact area is the same on all valves, but I assume it is. Is there any advantage (the hot rodders like them this way) or disadvantage (the manual says not to do it) of the contact area on the valve being towards the outside circumference of the valve head.

With the seat at the outside edge of the valve it increases the effective diameter of the valve. I'm not sure what the downside is other than maybe a ridge on the seat could form the valve pounds in, and the valve can sink. I'd just go with it since everything is assembled now.

Don, is that 104 intake 106 exhaust?

How did you arrive at those? Just curious, it's very close to what my head guy has told me to set them to (though I'm using the 550 exhaust cam.)

It is actually 105 intake and 106.625 exhaust. I found I did have the data at work.

I was aiming at 104:106 or 105:107 as suggested by RAPIDRAY, lower numerical figures for more torque.

I could not get these exact figures as you would probably know if you've done cam degreeing before that once the cam sprocket bolts are loosened the camshaft will slip into a different position as dictated by the spring pressure and valve buckets & shims. I was shooting for 105:107, but I ended up with 105:106.625, it was close enough for me.

An interesting fact is the cam timing on the 650 cams in standard trim actually has the numbers reversed.

Going off Suzukis cam timing figures in the manual the lobe centres are EX - 103 and IN - 106.

When I checked the standard 650 cams in my motor before slotting the cam sprockets, i.e. standard timing - I found they were EX - 103 and IN - 108.

As you will see these standard figures are back to front to the way Suzuki cams are usually ground and timed. Normally the EX is the larger number and IN the smaller number, but on the 650 cams it was the other way round. Don't know why, anyway I timed mine in the more standard way as I said previously looking for 105:107 intake and exhaust respectively.

BTW is there any reason why you are using the 550 exhaust cam?

Hope this helps and not too confusing.

Don, is that 104 intake 106 exhaust?

How did you arrive at those? Just curious, it's very close to what my head guy has told me to set them to (though I'm using the 550 exhaust cam.)

Hey there Don, good to see you making progress. Maybe you could give us a nice camera shot of the end of the camshafts from the right side of the motor. The slot cut in the end of the camshafts should be parallel to the valve cover surface on both cams. It looks like in the picture above, 3rd from the last, that the intake cam is retarded by one tooth.....Billy

Billy, I have degreed the cams in previously, 104 & 106 I think from memory. I am at work now so don't have the details with me. So I just reinstalled them as per the timing marks on arrow 2 and arrow 3 with 19 pins in between. MLINDER is right. I will get you a pic when I get home tonight.

TEAMDAR commented that putting a thicker base gasket on would advance the cam timing, so how much would .010" advance the timing and would the numbers be higher or lower, closer or further apart.

Hi Don,

Was looking though the parts fishe and apparently Suzuki did away with the cylinder head chain guide thing between the cams in 1981 for the 550 and the 650's never used them. Think I'd ditch it but the call is yours.

Ed I had a look at the parts fiche as well and the 550 used that top chain guide up until 1980 and they dropped it as well for the 1981 model 550. I will run it with it in place and if I still have trouble will remove it and see how things run then. Thanks for the input.

Any thoughts on the hot rodders liking the valve wear area on the outer edge of the valve face as mentioned in your previous post.

Thanks.

Billy, it looks to me like the tooth is correct, but he's slotted the cam gear and it looks like maybe the degree it's off is the same amount he's timed the cam at?

I could be wrong.

Hey there Don, good to see you making progress. Maybe you could give us a nice camera shot of the end of the camshafts from the right side of the motor. The slot cut in the end of the camshafts should be parallel to the valve cover surface on both cams. It looks like in the picture above, 3rd from the last, that the intake cam is retarded by one tooth.....Billy

[Nessism]

Hi Don,

Was looking though the parts fishe and apparently Suzuki did away with the cylinder head chain guide thing between the cams in 1981 for the 550 and the 650's never used them. Think I'd ditch it but the call is yours.

[TeamDar]

That base gasket looks pretty nice. I think it will seal just fine. You realize that changing base gasket thickness will alter your cam timing a bit, advancing it since you went thicker. Dar

More progress

More progress as follows.


Cylinder head fitted and torqued down.




Camshafts fitted and timed.







Cam Chain Tensioner fitted.




I had another thought while I was working on the motor today. There is a difference between the 550 and 650 cam timing. The 550 is 20 chain pins between timing marks and the 650 is 19 pins between timing marks. If I still have this noise after the motor is all reassembled another option i have is to take the 650 cams out and try the 550 cams in their place but not degreeing the cams in, just timing them as standard without slotting the sprockets.

A little more progress

Well, I made up the new base gasket from the .8mm oil resistant gasket sheet I bought. I found a new way to punch holes in gaskets. I had an old set of 650 cylinders, so I removed the liners and laid the gasket material on top and did what you see in the following pics.




Below: Set of cylinders with liners removed.








Measuring cylinder liners to be able to make appropriate holes in gasket.



Gasket during process of being cut out, a bit tedious.






Gasket as fitted ready for cylinders to be fitted.



Cylinderss being fitted onto pistons, hopefully for the last time. Getting good at this now.



Cylinders fitted.









.

So Don, hows the re-assembly going?

I'm glad you ran into this problem before I did so I make sure to check.

Keep us updated.

Slowly, but surely I hope. Don't want to pull it down again. Although I am getting good at it now.

I installed the valves, springs, etc. in the head yesterday and last night removed the cylinders that had been installed on the pistons/motor. Motor is back in frame now. Don't know whether I will pull it again to install the cylinders. I haven't installed the cylinders with the motor in the frame before, it has always been on the work bench. I'll see how I go getting the cylinders back on with the motor in the frame, if it proves difficult then it is only about 1/2 an hour to undo engine mounts and get it on the bench again. Remember I am doing this all by myself (putting the cylinders on the pistons I mean), my still at home son can give me a lift to get the motor out and put it back in again.

I measured up the holes in the OEM base gasket after pulling the cylinders and now know what size hole punches I need, so hope to get some today. We don't have the selection you guys in the US have for tools, so I am hoping I can find the 10mm and 13mm punches I need to make the new .8mm thick gasket.

ED: As you will have now realised I have fitted the valves back into the cylinder head, so am not keen to pull them all out again to check if the contact area is the same on all valves, but I assume it is. Is there any advantage (the hot rodders like them this way) or disadvantage (the manual says not to do it) of the contact area on the valve being towards the outside circumference of the valve head.

[Nessism]

Contact location on the valve is way out on the outside. Some hot rod guys like this location but the manual calls for the contact area to be more centered on the valve face. Doubtful to cause noise but something to keep in mind when talking to your machinist.

So Don, hows the re-assembly going?

I'm glad you ran into this problem before I did so I make sure to check.

Keep us updated.

Thanks Billy & Ed for your replies.

I went through the process of checking if any of my valves were bent tonight. I set each valve up in the drill chuck (only finger tight) and spun them with a dial gauge stand set up next to them as a reference to see if there was any wobble in said valve.

They all appeared to be OK. No run-out or issues with the head of the valve.

http://s226.photobucket.com/albums/dd105/donclifton/Valve%20Check%20movie/?action=view&current=P1000858.mp4

.