2v valve setting issues, mainly with closers

[cobrajet]

My 06 800 has not been started for about 4 months. Pulled all the covers and checked valve clearances, have reset openers a number of times but the closers were always withing the generous factory range. It may have been a liitle longer since my last check, has 78K on it now. Openers still measured decent, none greater than four, tightest at one and a half. Horizontal closers were too loose but not too bad but the verticals were way out, probably double where they should have been. Still had factory opener shims that were all marked so I went by that and bought new opener shims all around. Started on the vertical cylinder intake, in the end the shim I bought based on 2 thousanths clearance was way too thick, had to go two sizes smaller. Then I went on to the exhaust, same issue, my calculated shim was way to thick. After swapping out the closer shim numerous times now the opener clearance seems to have opened up over 3 thousanths more. It appearsa as if for one I'm not getting the keepers seated right in the closers and now the valve isn't seating fully. I've been using feeler gauges for fortyfive years but I'm missing something here. I pretty sure all my original measurements were made at TDC on compression for that cylinder but someting is going on. Pretty sure my unit conversions were all good too, used my favorite calculator and I am a Mechanical Engineer. Maybe old age is catching up with mme somwhere on this. Any suggestions?

[Speeddog]

'06 S2R800 with 78k miles?

You have to put the half rings back in the same way, that'll make a difference
half rings may be a bit too worn.

[cobrajet]

Thanks, I had wondered about that!  Update: Putting the half-rings back the same way they came out did change the clearance by 3 to 4 thousands. Measurements are making sense now.

[EEL]

Buy some MBP collets and never have half ring issues again.

[jduke]

I hate half rings...

http://emsduc.com/product-category/mbp-retainers/

[Duck-Stew]

Openers still measured decent, none greater than four, tightest at one and a half.

Smallest opener clearance I've ever heard of is 0.003" and that was by the factory manual on an '05 ST4s (996 motor).  Most 2V motors I've worked with are 0.004" minimum.

So are you actually setting them to 0.0015" when you type the above statement? Just wanted to clarify...  Seems super tight to me because opener tolerance tightens up when the motor gets hot (conversly the closers open up).