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Discussion Starter #1 (Edited)
so how necessary is it really to check valve clearance on an 'experienced' engine? my service manual suggests every 16,000 miles through pretty much forever. i certainly understand the need to check and adjust accordingly for a bike that isn't old, but for one that has, let's say, 50K+ miles on it, as long as the engine sounds fine and you aren't noticing any issues, do you really need the periodic clearance checks? what's the likelihood that you will need to adjust something?
 

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Valves tighten and loosen over time. Exhaust valves can burn if they get too tight. Intake valves get loose.
I know my bike has 20k miles on it and although the person I bought it from said service was done by a local shop but for piece of mind, I will probably adjust them soon as it gets a little warmer outside. Need to order o rings for the covers because I am not going to chance a leak.
 

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Henry David Thoreau once said "If I hung a picture on a nail hammered into plaster, I would not be able to sleep at night".

Adjusting the valves on your motorcycle is one of these things. You cant see them, you can sort of hear them, but the only way to know for sure if they are too loose or tight is to check them.

If you check them at the interval in the manual and they are ok, and ok the next time, you can consider not checking them as often as the manual calls for. But considering what is at risk if they go out of spec, two hours and 4 O-rings is nothing compared to having a valve drop into the cylinder.

Personally working on a nice, clean, not rusty, simple machine like a motorcycle is an enjoyable afternoon all in itself.

If someone really hates the idea of this kind of wrenching, there are motorcycles with hydraulic lifters.

There is a paradox in manufacturing: You want your products to be perfect when you ship them to your customers, so you test each one to make sure it works.

If you never find any problems in your tests, you are wasting your time testing them. If you catch one or two failures out of hundreds, you are doing about right. If half the tests fail then your production line needs to be improved. Its like that - if you check your valves and they are way out, you are not checking them often enough - if you never need to adjust them because they are always in spec, it feels like you just wasted 2 hours.
 

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after 20,000 miles i adjusted mine to tighter side of the spec, i check them each winter and they have not changed yet and i'm at 60,000 this winter, slappy valves might be happy valves but they also wear faster from banging into the seat harder and the rocker screw smacking the valve stem harder, shop manuals usually say adjusting valves to the tighter side of the spec gives the best performance but i would not do that until the engine is well broken in, when you get the adjustment right there should be just a hint of a tick, not noise you can hear from three feet away
 

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after 20,000 miles i adjusted mine to tighter side of the spec, i check them each winter and they have not changed yet and i'm at 60,000 this winter, slappy valves might be happy valves but they also wear faster from banging into the seat harder and the rocker screw smacking the valve stem harder, shop manuals usually say adjusting valves to the tighter side of the spec gives the best performance but i would not do that until the engine is well broken in, when you get the adjustment right there should be just a hint of a tick, not noise you can hear from three feet away
Did you replace your rocker cover o rings or just reuse the old ones?
 

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the o rings are $4 each

if you don't replace them and they ooze, its 2 hours to get the tappet covers off again

on the 650 the only one you can replace with the carbs still on the bike is the exhaust tappet cover on the rear cylinder.

also if you pull the cam covers off to see the timing mark on the cam gears there are o rings on those too...

if nothing else at least put some silicon grease on them.
 
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