Opener measurements

[svr]

Got a few questions on valve checking subtleties that I haven't found discussed.
1. When checking the opener should u check with or without the little spring clip installed?  The one u remove to slide the rocker over.  This is related to the following questions too

2. I get a slightly different measurment if I slightly pull up on the rocker. If u pull up on it it would be the max possible clearance whereas if u just let the rocker rest the feel of the gauge is different and can give a different measurement.

3. The difference between the two methods is more pronounced when u leave that clip in place since it puts a little lateral force on the rocker. I assume this just makes it slighly more difficult for the rocker to come to rest and that can result in a different feel on the gauge.

4. When doing the closer and pushing down on the rocker should I lightly make sure the shim is seated agains the rocker by pushing down lightly on the valve?  Then measure the new opener clearance to get the difference. Same question applies here to pull up on the opener while pushing down on the closer?

Hope this makes sense. IM a perfectionist and this is my first valve check and I wanna get it perfect. By the way 99 m900 2v.

Any feedback and tips much appreciated !

[Speeddog]

1. I measure without the clip.

2. I don't pull up on the rocker.

3. See #1 and #2...

4. I measure closer clearance directly.

[uclabiker06]

When/if you remove your shims for replacement, stick a screwdriver in your valve hole (where your spark plug goes ) to make sure your valve doesn't drop in there.  You can use a forceps as well but i like a screw driver better.  As far as measuring the closers you don't have to make sure anything is seated, just push down and measure.  Your probably wont have to push down on the rocker as hard as you think. Just firmly and then get the measurement.

[svr]

thanks for the tips.  i thought i'd follow up since i think i've got it figured out now.  It turns out that those clips tend to deform when you remove them.  I pulled all of them and they were all skewed effectively making them wider than they should be (thank you lt snyder manual!).  Bent them back to normal width with some pliers and now they don't exert lateral force on the rockers.  In this condition, i can get the same measurment with or without the clips installed and with or without lifting on the rocker.  Much more consistent measurements.  When those clips are squeezing the rockers they don't move up and down as easily, so you can get erroneous measurements because the feeler gauge is also counteracting the force of the clip.  totally makes sense to me now. 

So, here's what i did:  Pulled clips, measured with and without pulling up on rocker.  Bent the clips back properly, reinstalled and measured again.  Pretty consistent now.  Turns out i had oversanded 2 of my openers due to bad readings caused by the clips.   Small price to pay for my increased confidence now.

To me, these are a couple subtleties that don't seem to be addressed with most tutorials, and in my case were absolutely critical.  Hopefully, this might help others out there learning to do valves.  It's actually kind of fun to do the valves (at least on my 2v).  super rewarding to do your own service.  feel more like i understand the machine a lot better and it's cool to be able to say yeah those duc valves really aren't that scary.   

[junior varsity]

When/if you remove your shims for replacement, stick a screwdriver in your valve hole (where your spark plug goes ) to make sure your valve doesn't drop in there.  You can use a forceps as well but i like a screw driver better.  As far as measuring the closers you don't have to make sure anything is seated, just push down and measure.  Your probably wont have to push down on the rocker as hard as you think. Just firmly and then get the measurement.

I like the forceps best because it keeps the valve from falling down even the smallest bit (if leveraged against the opening for inspection cover).

[junior varsity]

1. I measure without the clip.

2. I don't pull up on the rocker.

3. See #1 and #2...

4. I measure closer clearance directly.

This is how I was taught by ol' Stuart Rust. I learned on a head off the bike, but other than needing to limber up for the gymnastics involved if you don't have a lift, its no different than on the bike. Top Dead Center so valves don't fall done in case you screw up, bolt in the oil drain hole - those f*#$ing collets like to disappear.

[uclabiker06]

"Those f*#$ing collets like to disappear."

Do they ever!  Congrats svr, its wonderful, isn't it. 

[junior varsity]

also, collets are a little fragile and you'll occasionally find one broken in half when you get ready to inspect that lower shim.

[svr]

Turns out it had Mbp collets installed so that's a nice surprise. 

[uclabiker06]

Nice!

[junior varsity]

That is a yahtzee! I've got a set for the 900 motor I'm building as well. Can be a bit of a pregnant dog to put in.

[svr]

It took me about two hours to get them on the horizontal exhaust the first time. After I figured out my method I can have them off and in five minutes.  Just gotta rotate engine enough to be able to pust the rocker pretty far down. Set the collet in the stem and just slide it down the stem and it falls right in place. Real hard on that front exhaust laying on the ground.