The OBSERVED Valve Clearance thread

Inhouse Bob_imp said:
This discussion leads me to question my own situation. I generally wear pretty good ear protection and the engine sounds like the proverbial sewing machine all the time. But once in a while I will forget the ear plugs and everything is louder. That's when I notice that under pretty good acceleration I hear distinct ticking from the engine. It runs as it always has with no discernible difference over time. So, is this the injectors doing their thing or valves rattling around? It's got 15k miles on it, mostly casual riding though I do prefer to keep the revs elevated (3500 to 4500 RPM are normal, I guess).
Or maybe I should just put my earplugs back in :angel:
Click to expand...
I'd say, that ticking is produced by the injectors. Anyway, wearing of the valve drive system of the CB1100 would reduce the play of the valves, not increasing (and causing ticking). The risk is, after wearing too much, the out valves wouldn't really close anymore and would get burned.

You can see that at Cormanus' valves new clearance list.
 
Django_imp said:
Inhouse Bob_imp said:
This discussion leads me to question my own situation. I generally wear pretty good ear protection and the engine sounds like the proverbial sewing machine all the time. But once in a while I will forget the ear plugs and everything is louder. That's when I notice that under pretty good acceleration I hear distinct ticking from the engine. It runs as it always has with no discernible difference over time. So, is this the injectors doing their thing or valves rattling around? It's got 15k miles on it, mostly casual riding though I do prefer to keep the revs elevated (3500 to 4500 RPM are normal, I guess).
Or maybe I should just put my earplugs back in :angel:
Click to expand...
I'd say, that ticking is produced by the injectors. Anyway, wearing of the valve drive system of the CB1100 would reduce the play of the valves, not increasing (and causing ticking). The risk is, after wearing too much, the out valves wouldn't really close anymore and would get burned.

You can see that at Cormanus' valves new clearance list.
Click to expand...
Thanks Django. That's what I thought, but paranoia is what it is. Now, off to change the oil!
 
Thanks Cormanus and Django for the good info.

After staring at the updated ( ta ) spreadsheet for a while and thinking about what it is that is actually wearing it appears that the only thing that could cause the clearance to decrease as it does is the valves and seats as they work their magic after the cams and buckets have seated in and polished up on the contact surfaces, it almost becomes predictable.

What a useful thread this turns out to be, thanks Cormanus for providing so much insight in our valve system.
 
I wish only that I understood my contribution. But you’re welcome. :cool:
 
:rofl: Don't feel bad Cormanus, I didn't get anything from your chart other than a bunch of numbers. Don't know what those numbers mean though. Good thing we are smart when it comes to moderatin' :rolleyes:
 
Inhouse Bob_imp said:
This discussion leads me to question my own situation. I generally wear pretty good ear protection and the engine sounds like the proverbial sewing machine all the time. But once in a while I will forget the ear plugs and everything is louder. That's when I notice that under pretty good acceleration I hear distinct ticking from the engine. It runs as it always has with no discernible difference over time. So, is this the injectors doing their thing or valves rattling around? It's got 15k miles on it, mostly casual riding though I do prefer to keep the revs elevated (3500 to 4500 RPM are normal, I guess).
Or maybe I should just put my earplugs back in :angel:
Click to expand...
I don't think anything went out of the spec after 15k miles... Air cooled engines are always more noisy compared to liquid cooled ones...

Also, here are my measurements.
Odo is 36k miles, last check was at 12k miles at dealer's shop and I believe no adjustment has been done.
(measurements are in mm)

Clearance; Old shim size; (Old shim marking); New Shim Size
Cyl 1:
Ex
0.31 2.012 (200) 2.050
0.33 1.976 (198) 2.025
In
0.18 2.027 (202) 2.050
0.19 2.027 (202) 2.075

Cyl 2:
Ex
0.30 1.930 (192) 1.950
0.33 1.928 (192) 1.975

In
0.18 2.029 (202) 2.050
0.20 1.981 (198) 2.025

Cyl 3:
Ex
0.32 1.910 (190) 1.950
0.32 1.908 (190) 1.950
In
0.19 1.979 (198) 2.025
0.19 1.956 (195) 2.000

Cyl 4:
Ex
0.30 1.910 (190) 1.925
0.30 1.915 (190) 1.925
In
0.21 1.956 (195) 2.025
0.21 1.981 (198) 2.050

The numbers of existing shims look not round. I think part of the reason is because I used inch micrometer and converted all values to mm. Probably some systematic error is involved.

My bike is '13, I typically keep revs between 1.5 and 4k PRM unless this is 5th gear and there is no next gear to gear up. I also accelerate aggressively most of the times.
 
Great. Thanks for posting, Jurlie.
 
Cormanus_imp said:
Great. Thanks for posting, Jurlie.
Click to expand...
You're always welcome!
I've realized it will be useful to list shim sizes marked on them. Will fix that tomorrow as it gets late today...
 
Thanks Jurlie, the reason for the old and new shim sizes is simple;
1 we get an idea what shim sizes and how many are required and;
2 we learn about valve clearance behavior in our bikes.

As far as i can work it out my cb919 and the cb1100 use the same size shims ( 7.48 mm. ) and also the same shim thickness ( ranging from 1.95 to 2.05 mm ) and we need more than 3 as supplied with the usual kit of the same size.

For a quick overview we created this thread and a spreadsheet for this purpose;
observed valve clearance thread google spreadsheet
as of yet i have only bought shims with 0.05 mm interval but would like to get the in-between 0.025 interval as well for the future.

Out of interest did you un-tension the cam chain when measuring?
 
max_imp said:
Thanks Jurlie, the reason for the old and new shim sizes is simple;
1 we get an idea what shim sizes and how many are required and;
2 we learn about valve clearance behavior in our bikes.

As far as i can work it out my cb919 and the cb1100 use the same size shims ( 7.48 mm. ) and also the same shim thickness ( ranging from 1.95 to 2.05 mm ) and we need more than 3 as supplied with the usual kit of the same size.

For a quick overview we created this thread and a spreadsheet for this purpose;
observed valve clearance thread google spreadsheet
as of yet i have only bought shims with 0.05 mm interval but would like to get the in-between 0.025 interval as well for the future.

Out of interest did you un-tension the cam chain when measuring?
Click to expand...
I had no idea they are sold as a set. First thing that I've found are individual shims on Partzilla or BikeBandit for $6 a piece. I've ordered and waiting for delivery currently.
max_imp said:
Thanks Jurlie, the reason for the old and new shim sizes is simple;
1 we get an idea what shim sizes and how many are required and;
2 we learn about valve clearance behavior in our bikes.

As far as i can work it out my cb919 and the cb1100 use the same size shims ( 7.48 mm. ) and also the same shim thickness ( ranging from 1.95 to 2.05 mm ) and we need more than 3 as supplied with the usual kit of the same size.

For a quick overview we created this thread and a spreadsheet for this purpose;
observed valve clearance thread google spreadsheet
as of yet i have only bought shims with 0.05 mm interval but would like to get the in-between 0.025 interval as well for the future.

Out of interest did you un-tension the cam chain when measuring?
Click to expand...
I was following the manual: using special tensioner tool for a hundred bucks I've screwed tensioner clockwise as much as it allowed. Was that un-tensioning?


For moderator:

could you please replace the numbers in my previous comment with following? I've added the shim marking.

Clearance; Old shim size; (Old shim marking); New Shim Size
Cyl 1:
Ex
0.31 2.012 (200) 2.050
0.33 1.976 (198) 2.025
In
0.18 2.027 (202) 2.050
0.19 2.027 (202) 2.075

Cyl 2:
Ex
0.30 1.930 (192) 1.950
0.33 1.928 (192) 1.975

In
0.18 2.029 (202) 2.050
0.20 1.981 (198) 2.025

Cyl 3:
Ex
0.32 1.910 (190) 1.950
0.32 1.908 (190) 1.950
In
0.19 1.979 (198) 2.025
0.19 1.956 (195) 2.000

Cyl 4:
Ex
0.30 1.910 (190) 1.925
0.30 1.915 (190) 1.925
In
0.21 1.956 (195) 2.025
0.21 1.981 (198) 2.050
 
Thanks Jurly, you're right on the money, inserting the tool and screwing it in is the right way, also see this thread;
http://cb1100forum.com/forum/showthread.php?tid=8677

For anybody who needs such a tool here is a youtube video with an alternative:

And here is what i made and just tested on my cb1100;



It is made out of 1 mm. copper sheet because it was easy to cut and is strong enough to do the job, i have previously used it on my cb919 hornet, the bolt next to it is m6 for size reference.

Thanks again for all your work, when i have some time i will enter it into the spreadsheet if that's ok with you.
 
Jurlie_imp said:
max_imp said:
Thanks Jurlie, the reason for the old and new shim sizes is simple;
1 we get an idea what shim sizes and how many are required and;
2 we learn about valve clearance behavior in our bikes.

As far as i can work it out my cb919 and the cb1100 use the same size shims ( 7.48 mm. ) and also the same shim thickness ( ranging from 1.95 to 2.05 mm ) and we need more than 3 as supplied with the usual kit of the same size.

For a quick overview we created this thread and a spreadsheet for this purpose;
observed valve clearance thread google spreadsheet
as of yet i have only bought shims with 0.05 mm interval but would like to get the in-between 0.025 interval as well for the future.

Out of interest did you un-tension the cam chain when measuring?
Click to expand...
I had no idea they are sold as a set. First thing that I've found are individual shims on Partzilla or BikeBandit for $6 a piece. I've ordered and waiting for delivery currently.
max_imp said:
Thanks Jurlie, the reason for the old and new shim sizes is simple;
1 we get an idea what shim sizes and how many are required and;
2 we learn about valve clearance behavior in our bikes.

As far as i can work it out my cb919 and the cb1100 use the same size shims ( 7.48 mm. ) and also the same shim thickness ( ranging from 1.95 to 2.05 mm ) and we need more than 3 as supplied with the usual kit of the same size.

For a quick overview we created this thread and a spreadsheet for this purpose;
observed valve clearance thread google spreadsheet
as of yet i have only bought shims with 0.05 mm interval but would like to get the in-between 0.025 interval as well for the future.

Out of interest did you un-tension the cam chain when measuring?
Click to expand...
I was following the manual: using special tensioner tool for a hundred bucks I've screwed tensioner clockwise as much as it allowed. Was that un-tensioning?


For moderator:

could you please replace the numbers in my previous comment with following? I've added the shim marking.

Clearance; Old shim size; (Old shim marking); New Shim Size
Cyl 1:
Ex
0.31 2.012 (200) 2.050
0.33 1.976 (198) 2.025
In
0.18 2.027 (202) 2.050
0.19 2.027 (202) 2.075

Cyl 2:
Ex
0.30 1.930 (192) 1.950
0.33 1.928 (192) 1.975

In
0.18 2.029 (202) 2.050
0.20 1.981 (198) 2.025

Cyl 3:
Ex
0.32 1.910 (190) 1.950
0.32 1.908 (190) 1.950
In
0.19 1.979 (198) 2.025
0.19 1.956 (195) 2.000

Cyl 4:
Ex
0.30 1.910 (190) 1.925
0.30 1.915 (190) 1.925
In
0.21 1.956 (195) 2.025
0.21 1.981 (198) 2.050
Click to expand...
Done
 
Hi all, I am tommy and i am new here. recently I have just done VC and found the following

Cyl 1:
Ex
0.30, 0.31
In
0.18,0.18

Cyl 2:
Ex
0.30, 0.30

In
0.18, 0.18

Cyl 3:
Ex
0.30, 0.30
In
0.15, 0.15

Cyl 4:
Ex
0.28, 0.30
In
0.15, 0.18

Just wondering if the valve clearance will increase or decrease over time since most of my exhaust valve is on the loose side. Also what's the torque for 4 bolts on the camshaft cap? I have popped a cylinder head cover bolt and have to remove the camshaft cap to machine and remove the broken stud. due to that experience, i just tighten the camshaft cap lightly due to fear of another broken bolt. so are all cylinder head cover bolts, just slightly hand tighten.
 
Welcome aboard zirconxi. Thanks for posting your valve clearance results. How many kms has the bike travelled?

Which model CB1100 do you have and how long have you had it? Maybe head over to the new members section and introduce yourself.
 
Cormanus_imp said:
Welcome aboard zirconxi. Thanks for posting your valve clearance results. How many kms has the bike travelled?

Which model CB1100 do you have and how long have you had it? Maybe head over to the new members section and introduce yourself.
Click to expand...
Hi Cormanus, the bike is a 13 model and had travelled 30,000km, I bought it since 3 years ago when she just clocked in at 6500km. Will do a proper introduction once I found the new member section, kind of lost in the forum, :)
 
Welcome Tommy!

Cylinder head cover bolt—7 ft lbs.
 
Hi Tommy, welcome to the forum and thank you for posting your vc's.

I don't claim to be a mechanic but i like to know "what makes things tick" and have always done my own maintenance on my vehicles so take my advice with some skepticism and if anyone has a better explanation i would like to hear it so we all can learn something and improve ourselves

The impression i get from reading the spreadsheet is that initially when the engine is new the cams and buckets are not " polished in " , they are ground and have to achieve their high polish over time as the engine runs in and they rotate in their position as can be seen from the markings on the top of the buckets, who are truly worn round, this is done on purpose, all cams are positioned eccentric so the area of "wear" is as big as possible to prolong the life of the engine and to extend the valve adjustments increments.
For this reason it is important that the buckets do not get mixed up and all end up in their respective seats and the shims are placed with the text facing up on top of the valves where they have the biggest mechanical support area and have lubrication applied when re-inserted in their position
These area's are a lot bigger than the original screw adjustable tappets from the old style and retain an oil film much better.

During this time the valves also run in and settle on the seats, they do not rotate and are always under spring tension.

So in the "settling period" anything can happen, the clearance can get bigger or smaller depending on how good the technician at the time installed the valve clearance and if there are deposits that settle on the seat surface and decrease the vc, this is picked up at the first vc check.

The trend is for them to increase the vc so the shims are replaced with bigger sizes ( best are done with 0.025 mm. shim intervals ) but there is the odd one that gets smaller, so it depends.
The valve system is designed to have long vc intervals and slowly increase as the valves wear the seats down over time.

Generally small vc is bad because the valve can fail to close, not cool enough and consequently burn ( melt ) when the engine heats up, but a loose valve is not such a bad thing although it wears faster and is noisier, it still cools enough as the seat transfers the heat from the exhaust gas when it is closed.
 
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