To do or not to do Valve adjustment

[regaliz2]

Hello guys,

My bike is close to 24,000 km (15,000 miles), I did the valve adjustment when the bike had 600 miles and everything was ok, I mean all the clearances where in their normal values. I do not know if I should do the valve adjustment now or I should wait till theis do their characteristic sound, does anyone has done valves adjustment even if they aren't noisy and have found any of them out of clearance?

Thanks for your help  

Vssss

[oremike]

The manual calls for the valves to be checked every 15,000 miles or every 2 years. I get mine checked every winter but I put on about 18,000 a year.

[txbanditrydr]

Not to pick nits but the manual actually says every 7,500 miles for the valve adjustment.  I would highly recommend you check them now if they've only been adjusted once.

[chupacabra]

Most of the time they get tighter and you can't hear them, not loose and noisey. Too tight and they can ride the cam and won't hear any ticking. Best to check them before something bad happins, like a burned valve!

[Red01]

Yup, the book says 7,500 miles - or at least that's what my '01's owners manual says. If you skipped the 7,500 miles check, I would certainly do one now. Mine were checked at 600, 7,500 & 15,000 miles, after that, I just do them once every winter and I put ~10,000 miles a year on my bike.

If yours still look good at this 24K km check, I wouldn feel bad about extending the interval a little (obviously).

[ray nielsen]

Consider adjusting them to the maximum allowable specs.  That way you'll have the best chance of not needing adjustment quite so often.

On my 03 Bandit 1200 I set the valves to 0.006" intake and 0.009" exhaust at the 600 mile check.  Checked them at 7500, 15000 and 22000 and found them still at those dimensions.  Based on that I'll wait until 40000 unless the sound changes -- right now it sounds like sixteen mice all busy on manual typewriters!

Additionally, loose valves spend a bit more time on the valve seat dumping their heat into the block.  Even if they close up a bit they'll still probably be okay for longer intervals.

Just my two bits worth -- I ride in a touring mode and don't go near red line ever.  Maybe more often checks are called for with harder usage.

[snofrog]

as said above it`s when they are quiet that you need to worry . M

[regaliz2]

Thanks to all of you for your answers, it is 5 over 5, so I will check my valves. I have discover today little leakage from the nuts over the cam so I will change the gaskets of these nuts too.

Thanks for your help

Vsss

[fake]

I have a bit over 800 miles on mine.  I asked my service rep if they check valves at 600 mi; he just laughed and said they usually don't need it done.

However, I don't hear this "mouse on a type write" sound most of ya'll are discribing.  I hear a tapping sound but I have to listen hard for it.

[DaveG]

never in my life have i seen the valves get tighter.
they wear and the gap increases.
more likely if you find one tight is that it was improperly adjusted the last time.

so do them once yourself and double check everything after you manually turn the engine over a few times.

from then on leave them until they get noisey.

[Bob Holland]

never in my life have i seen the valves get tighter.
they wear and the gap increases.
more likely if you find one tight is that it was improperly adjusted the last time.

so do them once yourself and double check everything after you manually turn the engine over a few times.

from then on leave them until they get noisey.

Wrong, the valve head sets deeper into the valve seat, and they get tighter. Been building race engines for bikes for almost 40 years and the only time I have seen valves get loose is when something breaks.
 

[DaveG]

Well i've worked on engines (non race engines) since 1962 and like i said in my experience i have never found a tight setting when i know that the previous adjustment was done correctly.

i do understand your logic though.
if the valve was hader than the seat material that might happen.


just my personal experience

yours may differ.


so maybe the answer is "check"  the adjustment at the rrequired intervals.

[Bob Holland]

The valves actually deform, it is refered to as tupliped, It ruined the valves, but the seats are not normally hurt. This is basically a motorcycle problem because the valves are small and thin.

[Red01]

I'll go along with what BHolland said. I've never seen car or aircraft valves get tighter, but I have seen it on bikes. The SACS family of engines, which the B6-B12 are part of, are well known for this kind of behavior during break-in. By the 15K miles check they're usually done moving.