Topic: '78 550 Valve Spring Seats

[mbspark]

I'm working on putting the bike back together. Tonight I lapped the valves and put them all back into place. When I took the valves off, I put each of them in a baggie, numbered with it's right position, but had a buddy help me. When I was taking one of the valves out of the bag, there was a rubber washer that none of the other 7 valves had. I'm guessing because my friend was helping when I took them out, I didn't notice the extra washer and he didn't say anything. This concerned me, so I went and looked at the parts breakdown for the valves and saw that there is an inner & outer valve spring seat.

On the picture here, they are number 11 & 12. Can anyone speak to what these are? All I had for all but 1 of the valves, was the stem, valve stem seal, 2 springs, 2 keeper clips and the retainer.



I tore the whole top end open all for replacing the valve stem seals. Here is a picture of the new vs. old.



 I really hope that makes the difference with the bad smoking problem my bike was facing. No matter what, I am learning a ton, thanks to this forum!

[That 70s Bike]

I have my '75 550 top end apart also right now. On mine they are steel thrust washers apparently so the 2 steel springs do not rub a recess into the aluminum head. 7 out of 8 times, oil leaves them stuck to the head Better check the head & confirm the rest are still there.
By the way, what valve spring compressor did you use?

[mbspark]

Thanks for the reply!

I'm going to pull one of the springs back out and see if they're there just hidden and stuck that I didn't notice.

This is the type of compressor I used:



I tried the kind with a fork the first time, but it was junk compared to this one.

[bryanj]

They are 2 hardened steel washer, one fits on the valve guide the other round it on the alloy head, its easy to loose them if you have had the head machined and cleaned and they are necessary