Quick clearance question

When you guys check your valve clearances sometimes there's a feeler that will go in but needs a push

do you take that one or the one that goes in smoothly?

Thanks

 

I will go out on a limb here and say your using feelers marked in inches as the primary size.
notice the .006 inch is considered 0.15mm AND 0.16 mm
use metric feelers
measuring is a go no go thing some drag can be expected. what you consider good is the way to measure , its your bike and method.
keeping in mind any thing tight on the low end will likely need to be changed next time around. any thing tight on the high end will be good for a long time

from what I see above exhaust #3 needs to be changed by your metric measurement but is good by your inch measurement
intake #4 is out of spec by by both metric and inch measurements.

how did you arrive at the metric measurements?

which ones did you have to give an extra push?

KD Tools 2274 is a metric feeler set and you can order at any parts store.

 

Actually after taking exhaust number three out I went back and checked intake number four and I can't get the seven thousanth in now not sure how I did before

But number 3 exhaust is out and I'm hoping that's why I hear some popping when the engine is hot and will go away when I get the correct shim in there

 

popping is typically a lean condition but start by getting your valves in spec

 

A feeler gauge is read as being "that number" when you can insert the gauge into, and remove it from, the gap being measured and only feel a slight drag.
If you have to force the gauge in, or pull it out, or if the gauge flexes from a straight push or pull, then the gap is narrower than the guage is meant to measure.

 

It's pretty subtle... not thinking detonation at this point.

 

If the cam lobe is not in the exact same place as the first measurement you may see a clearance variance.
I find being anal about position and taking the extra time to check my repeatability raises my confidence level in the results.

 

Subtle or not, it's there because you're lean. Valve clearances first, then mixture, then look for leaks (vacuum and exhaust).

 

I had done clearances end of last summer

And sync
And colortune and sync in the past two weeks and still there

If anything the plugs look slightly rich... which is why I went back to valves.

I'm of the opinion it's either that tight ex valve, a small ex leak I just can't find, or the 37 year old mufflers have not enough baffles left and I'll be hearing it forever

 

Wow,
Just went back to the old thread for last valve check... #3 Was tight then and totally missed it.

 

lean can leave black soot due to incomplete combustion or no combustion and burning every other compression stroke causing rich but lean. I think it is explained in info overload or lens catalog.
could be your enrichment circuit is not sealing

 

,

So I broke down and got a set of metric feelers (sorcery I tell you) and got the following measurements

now my question is if valves get tighter over time how is number 4 intake wide?

At a hundredth of a mm will it just come in spec on its own?

 

1/100th mm is insignificant. how did you even measure/estimate that.
if your going to split hairs, get that.13 up to .14 or .15 or a real tight .16 then get that .17 up to .19. look for the difference between highest and lowest, keep that as small as you can
shims aren't exactly what their marked. two shims marked the same will never be exactly the same
you can use this https://drive.google.com/file/d/0B4...ZDFlLTg0YzgtNDU1ZjFlMTRhNjFi/view?usp=sharing
and only guess at the cam position once, then just go to the next line

 

The difference between .15 and .16 is 1/100 of a mm, no?

 

only 1 shim out of spec with metric tool . much better.

simple response . out of spec is out of spec.
measure your shim and then measure a few 290 shims you may be able to get one that will bring you in spec

 

yes, .0004 thousandths of a inch. but in is in, out is out. the line has to be somewhere. that's why you don't set to the low end, 10 people will read feeler gauges 5 ways
if you were to clean all the oil off you'd measure different

 

Should have mentioned that I already changed the number three exhaust shim so that's why that one is in Spec

the number four intake is still loose though

 

Scary lesson learned last night:

Always re-check clearances before putting it back together...
For some reason I mistakenly removed intake shim 3 instead of four... put it back and pulled four to see what size shim was there for ordering the new one.

Put it all back together without changing either of those shims while waiting for them to come in.
Number 3 intake shim was not fully seated / hung up in holder... started engine to awful racket and cold number 3 pipe.

Shut it off and disassembled again... found ZERO clearance on #3 intake... removed, checked for debris and reseated... all good. Must have been cocked a little in holder.

Engine runs fine but thought for sure I had run the valve into the piston

 

Got that last shim changed today... running sweeeeeettt...

 

Better to turn the engine over with a spanner Tim O the same thing happened to me with a shim not seated right. I heard it snap into place when I turned the engine manually. All my valve clearances are now on 0.20mm for the exhausts and 0.15mm for the inlets so I won't have to adjust them again for a long time I hope.

 

That's funny because I did and also heard that pop... and turns out it STILL wasn't seated all the way.

 

Yes well the main thing is your valves are ok I thought I had damaged a valve on my engine fortunately it was ok.

 

Yup, scared me to death ...

 

I am an amateur regarding maintenance, but I've learned two things when checking/replacing shims:

1) turn engine by hand to make sure they are seated, then recheck clearance before buttoning up.
2) wear goggles, sometimes when you pop the shim out of the bucket, oil will shoot right up into your face LOL

 

Yes you also have to watch that when spraying carb cleaner through the enrichment circuit jet in the float bowl. Cleaned mine recently if these are blocked fuel won't get to the engine for cold starts.