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My wife's bike just hit the 19,000kms and me thinking that valves were checked every 24,000kms thought I was in the clear. To my surprise, the manual calls for a valve check every 12,000kms. For those that have gone over the 12,000kms, how far off were the valve clearances? Can I wait until 24,000kms or it is a ticking time bomb? This bike has been babied, I don't believe it has gone over 11000rpm.
 

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You are fine. The bike will let you know the valves need adjustment as the bike will become difficult to start.
 
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Most well maintained bikes that are not thrashed will have minimal valve clearance change at that mileage.
It is a valve clearance check....adjustments only required if a valve is found out of spec.
 
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The problem with ignoring valve lash check is the possibility of a burning an exhaust valve.
Which silentservice points out as the engine growing difficult to start..

I worked at Honda dealer back in the day.
This subject reminded me of all the mini trail bikes that would come in for "won't start" complaints after a long weekend.
The exhaust valve clearance would go negative when the engine was cold, so there was not enough compression for the engine to run.

That said: noisy valves are generally happy valves.
 

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Yes, and shim under bucket type valves (like on our MVs) tend to get tight over time, not loose.
 
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Yes, and shim under bucket type valves (like on our MVs) tend to get tight over time, not loose.
My experience with DOHC valve train maintenance goes back to the early '80s, Honda and Kawasaki.
I remember having to adjust the shim over bucket on both brands frequently. But the shim under bucket rarely needed attention, providing the customer didn't abuse the engine and/or oil change interval.

So your statement both gives me comfort and dread,
I dread the thought of having to "adjust" the valve lash on this engine.
 

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I did my valve check at 15,000 miles, so just about 24,000 km. 4 of my valves were out of spec, but not by much. Since it's been more than a year ago since I did the maintenance, I don't remember how many were intake or exhaust valves.
 

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I did my valve check at 15,000 miles, so just about 24,000 km. 4 of my valves were out of spec, but not by much. Since it's been more than a year ago since I did the maintenance, I don't remember how many were intake or exhaust valves.
Do you recall were the "out of spec" valves tight or loose? And asking a lot of your memory, by how much?
 

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I just went through my toolbox and happy to report that I still have the note that I jotted down during the maintenance procedure. Looks like 5 valves were out of spec. Not 4. The below were out of spec.

#1 Cylinder Exhaust (L), tight by 0.03mm.
#2 Cylinder Exhaust (L), tight by 0.04mm.
#2 Cylinder Exhaust (R), tight by 0.04mm.
#3 Cylinder Exhaust (L), tight by 0.01mm.
#3 Cylinder Inlet (L), loose by 0.01mm.

If you're interested in the full reading, I have that as well.
 

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I just went through my toolbox and happy to report that I still have the note that I jotted down during the maintenance procedure. Looks like 5 valves were out of spec. Not 4. The below were out of spec.

#1 Cylinder Exhaust (L), tight by 0.03mm.
#2 Cylinder Exhaust (L), tight by 0.04mm.
#2 Cylinder Exhaust (R), tight by 0.04mm.
#3 Cylinder Exhaust (L), tight by 0.01mm.
#3 Cylinder Inlet (L), loose by 0.01mm.

If you're interested in the full reading, I have that as well.
Thanks for sharing...
Considering the nominal go/no go values.
I probably would have put it back together, w/o adjustments. But that's me...
So far I've done my own maintenance.
It's been 40 years since I last busted into a DOHC valve adjustment; I really dislike having to remove the cams to shuffle or replace the buttons.
If you don't mind, about how long did it take you to get to the actual cam/valve interface?

Thanks again for your time.
 

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I didn't really rush through the process and worked at a leisurely pace over 3 weekends if I remember correctly. I couldn't have worked more than an hour at a time, and usually spent a day out of a weekend. The process was fairly straightforward, and the trickiest part for me was to get the throttle body out of the frame. I also spent masking tape the frame, labeling everything as well as ziplock individual components as I went through the process, so probably spent more time than an average person.
 

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Discussion Starter #12
Thank you very much for all the replies. Members here are great.
 

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Checked the valves on my Dragster RR this winter at about 25000km. 3 of the exhaust valves and 1 intake valve were tight. (0,04mm off at most)

Adjusted the valves and replaced the timing chain and related components, ”while I was in there”. The chain was starting to get a little noisy at cold starts, and it is supposed to be replaced at 36000km anyway.

All valves were within spec when checked at 12000km a few years ago.
 
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