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Valve adjustment negligence

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Deleted member 1344

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I am not yet ready for the 6,000 service/valve adjustment but am wondering what damage is done if I waited until say... 10,000 miles?
My guess is the clearance would increase rather than decrease. I once heard that a slappy valve is a happy valve.
 
Valves usually get tighter (less clearance) with more wear (the valve seat wears allowing the valve to sink lower into the valve seat decreasing the clearance). It can result in burnt valves, hard starting, etc. A tight intake valve can cause backfiring into the intake. Hypothetically the piston could possibly hit the valve. Usually, a bike will get hard to start if it has a tight valve, but I obviously wouldn't want to wait that long.

Have you ever heard a kid bump starting his old four stroke motocross bike because it won't start....?
 
I may have it backwards on the valve wear. Hopefully the nearest dealer will do the maintenance even though I bought it in Chicago. At the local HD dealer they always ask me if I "bought it here" whenever I approach the service desk.
 
Interesting thought LCRC18B, but I tend to lean more towards R12C-R18TC's assessment. one would hope that the valve seats are so nicely ground in that there should be negligible wear @ 6000 miles, I would think that here would be more material compression happening in the rocker arms and pushrods and thus increasing the valve lash ... and yes I also think that a bit a noisier valve is a lot less harmful than a valve that is more on the tight side ... as LCRC18B pointed out a burned valve seat is a real bitch !
... just my 2¢ 😁
 
Ulrich said:
Interesting thought LCRC18B, but I tend to lean more towards R12C-R18TC's assessment. one would hope that the valve seats are so nicely ground in that there should be negligible wear @ 6000 miles, I would think that here would be more material compression happening in the rocker arms and pushrods and thus increasing the valve lash ... and yes I also think that a bit a noisier valve is a lot less harmful than a valve that is more on the tight side ... as LCRC18B pointed out a burned valve seat is a real bitch !
... just my 2¢ 😁
Click to expand...
And this is why, when I started the valve adjustment thread, I asked if I is possible for valves clearance to get looser (more gap) then a new motor. When I did my 6k clearance, several were at the max, and 2 were @ 0.33-0.35. I suspect that at the 12k, they will all show, less clearance, then what I set them, @ 6k.
 
pbosik said:
And this is why, when I started the valve adjustment thread, I asked if I is possible for valves clearance to get looser (more gap) then a new motor. When I did my 6k clearance, several were at the max, and 2 were @ 0.33-0.35. I suspect that at the 12k, they will all show, less clearance, then what I set them, @ 6k.
Click to expand...
That will be very interesting to see, in your case we will have a real benchmark there .. you kept great records ... that will be a great baseline for future reference ! ... and thanks!!
 
Ulrich said:
That will be very interesting to see, in your case we will have a real benchmark there .. you kept great records ... that will be a great baseline for future reference ! ... and thanks!!
Click to expand...
I am interested in your findings, when you check your clearance.
 
forgive me for resurrecting an old thread. I just had my valves checked at the dealer. 21000km in the dial. Valves were reported on the loose end of the spectrum and were adjusted to 0.25mm for all valves.

When speaking with the tech, he said they really should be checked every 10000km to ensure it doesn’t move as the unbalanced nature of the motor can vibe them out of spec pretty quick.

Theoretically that makes sense…but also pretty wild to think they would freely adjust themselves out of spec that quick.

What are you guys finding with your valve checks and do they require adjusting every time?
 
Mine is booked for a service on June 4th. The valves will need adjustment as per schedule. Mine are well out of tolerances, especially my right cylinder, it has a clack clack clack noise similar to an old diesel engine. Only 8860 mls on the clock. By contrast, my old M109R never had the valves adjusted in 15years.
According to the service manual, they need adjustment every 6000 mls
 
On my second (12,000 miles) valve adjustment; I didn't have to adjust any of the jab nuts, all clearances measured within their target tolerance from the previous valve adjustment at approximately 6,000 MLS.

I do remember thinking that my bike's engine sounded smooth and not like Ulrich's millipede wearing tap shoes...
 
Star-Lord said:
On my second (12,000 miles) valve adjustment; I didn't have to adjust any of the jab nuts, all clearances measured within their target tolerance from the previous valve adjustment at approximately 6,000 MLS.

I do remember thinking that my bike's engine sounded smooth and not like Ulrich's millipede wearing tap shoes...
Click to expand...
Definitely agree the bike has less valvetrain noise now that it’s tightened up. Might be placebo here however my butt dyno feels like I picked up more low end power between 2-2700 rpm.
 
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