620 valve adjustment question

[K3V1N]

I'm doing the 6k on my 620 and I have it all apart but have a couple questions before I start adjusting.

On the horizontal cylinder this is what I found.

Opener at TDC I can get .002 halfway between the opener and arm.

Closer at TDC pushing down I can get .002 in easy and .003 but it is tight.

First off have others seen the openers that tight?

Second should I just sand the openers till I have the right opener gap?

Third since the closers seem to around .002 can I leave them if they spin and are under .005

Thanks,
Kevin

[redial]

disclaimer: not an expert

First off have others seen the openers that tight?

mm, my exhaust openers are .0025, intakes are .003 (checked them this week, changing next week) make sure youre at the correct top dead center. i put a screwdriver into the spark plug hole to check

2.

Second should I just sand the openers till I have the right opener gap?

yes you can just sand down your openers to make them the correct clearance. ive read its best to use a flat peice of glass to make sure that you are doing it flat. use a digital caliper to measure each side of the shim to make sure that you didnt sand it uneven.

Third since the closers seem to around .002 can I leave them if they spin and are under .005

um .002 is supposed to be the line, according to what i read, which happened to be ducatisuite.com i suggest you read it. good stuff.
.005 seems crazy loose. my closers range from zero to .0015.  although i need to remeasure, something about binding could cause misreads, havent fully looked into it yet

hope everything goes well, and post up your progress if you can

[K3V1N]

Thanks

I will double check I'm at TDC. I would say if I had to guess the openers are around .0014 and closers are around .0015 combined is just short of a smooth .003.

I will have to get some sanding supplies and take the big leap. Off with the belts

Thanks and if anyone else has had tight openers let me know.

[rule62]

What I noticed when the valves were adjusted on my 620 is that all of the closers were loose and the openers were tight.  This is most likely due to the closing collets (half rings) wearing in.  As they wear in, the closer shim sets further up on the valve stem, causing the looser closing tollerances.  Due to the closers loosening, the valves actually slide out a little causing the openers to seem tight. 

Before you go sanding down your opening shims, make sure your closers are set correctly first.  You may find that they don't need to be sanded at all.

[K3V1N]

OK, I have a couple more questions.

First can someone explain how if the keeper wear and the closing shims move up the valve the openers can get tighter?

Second my closers seem to be around .001 and my openers seem to be around .0015. It seems like I just have to sand the openers and reassemble but it bugs me they they are so tight.

Third question I have to belts off now how do I tell then the vertical cylinder cam is in the right position to check the clearance?

Thanks for your help.

[K3V1N]

Is there anyone out there that can help explain how the valve openers can be so tight? I understand the steps to finish the adjustment and belt installation but the tight valves confuse me. Was it set wrong at the factory and messed with by someone? I would think the openers could only get looser.

[Speeddog]

Valve face and valve seat wear will cause the closers to get looser and openers get tighter.

Half ring 'seating' will only cause the closers to get looser.

[K3V1N]

AAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!

That makes sense!

Thanks

[rule62]

I think that's more along the lines of what I meant.  Sorry for being so vague.

[K3V1N]

Thank everyone for your feedback. Now I feel comfortable moving forward and getting back on the road.

Any tricks to knowing where to put the vertical cylinder cam to check the top valves? I'm guessing anywhere that the valves aren't moving when I turn it?

[Speeddog]

Do yourself a favor and pull the belts off.
Leaving 'em on just makes the whole valve adjust a lot harder than necessary.

Just have to remember to make sure all the valves are closed before turning the crank.

Belt change and valve adjust videos here:
http://www.ca-cycleworks.com/videos/

[K3V1N]

UPDATE

You guys are going to get a laugh out of this one.
I got new feeler gauges and some other tools since I was going to do the 6k myself.

It turns out that sears feelers go .002, .0025, .003, .004 and so on.

Yup the .0025 was stuck to the .002. DOH!

I had started sanding one opener before I pulled out my trusty motion pro feeler I use on other bikes.

I could have used the sanded opener it was only to a snug .005 but I stopped my the dealer and got another 3.20.

All the openers where at .004 and the closers where .002. I have covers and new belts back on and hopefully will be on the road this weekend.

Thanks again for your help,
K3V1N