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Signs of a dirt bike needing its valves adjusted

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Are there any signs that can tell you your bikes valves need to be shimmed or ajusted? Just curious.

Thanks,

Mike

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Valves tighen as they wear. So hard cold starting is most often typical. A lot of guys check valve clearances during oil changes, I check mine every other change and note the numbers to detect a trend.

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and what is the worst thing that can happen if you run your bike when your clearences are bad?

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and what is the worst thing that can happen if you run your bike when your clearences are bad?

The valves will get wrecked and it will cost you $$$.

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The valves will get wrecked and it will cost you $$$.

That is not true. Dirt and over revving is what ruins valves.

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That is not true. Dirt and over revving is what ruins valves.

Not saying you are wrong but they can also go bad:

If the valves are out of spec it can cause excessive wear to the valves and the valve seats. And even possibly have valve slap on the piston if they are far enough out. Eventually a valve will break and possibly trash your whole top end. Take the time and check your valves. It will only take about 30 min to tear down and check them. If they need to be shimmed it will only take 45min to an hour max.

If your clearance is at -0- you can reshim back in to clearance. Recheck your valves again in about 10 hours after your shim job. If the clearance heads close to -0- again best bet is to go ahead and get your valves/springs/retainers replaced AND the seats recut. If you dont get the seats recut your new valves will be gone in no time.

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Not saying you are wrong but they can also go bad:

If the valves are out of spec it can cause excessive wear to the valves and the valve seats. And even possibly have valve slap on the piston if they are far enough out. Eventually a valve will break and possibly trash your whole top end. Take the time and check your valves. It will only take about 30 min to tear down and check them. If they need to be shimmed it will only take 45min to an hour max.

If your clearance is at -0- you can reshim back in to clearance. Recheck your valves again in about 10 hours after your shim job. If the clearance heads close to -0- again best bet is to go ahead and get your valves/springs/retainers replaced AND the seats recut. If you dont get the seats recut your new valves will be gone in no time.

how do you check the clearences? I have an 07 crf150r. Im new to this 4 stroke thing . Do you need any tools to check em?

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if they get tight enough, they can be hung open a little causing a loss of compression as well. if theyre too loose, they will tick.

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Hard start means 20 or more kicks, if you are even lucky enough for the bike to be kick started at all. When mine first tightened up it would backfire and would not start unless it was bump started.

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Pull the headcover off and check with some feeler gauges. Thats the way you tell if your valves need adjustment. Not waiting until the bike doesnt run.

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when valves wear they dig themselves into the head creating a smaller clearance...usually it will be hard to start, itll also have an erractic iele and poor low rpm preformance..then the valves cool down, the ti coating, if the valves are titanium, wears off and creates an uneven surface on the head...creating more damage on the valve..checking valves as well as adjusting them isnt that hard...you can prolly find a good step by step thread or maybe even a vid...but you will need to put the bike at top dead center on the compression stroke..in order to do this you will have to line up the marks on the flyweel..if the camshaft lobes are pointed in, turn the flywheel another 180 with a socket until the lobes face out (this is tdc on compression stroke)...then just use a good set of feeler gauges and measure the spaces bewtten the cam buckets and the camshaft lobe

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