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Who Here Adjusts Their Valves "By Feel"?

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I adjusted the valves on my '03 XR250 right before I stored it for the winter, and I've noticed that since doing so.. it seems harder to start, and my valves seem to be louder when the bike is cold than I recall them being prior to the valve adjustment. It could just be all in my head... but I'm thinking that this is less than likely the case.

When I adjusted my valves, I had to loosen them all just a slight bit to get them in spec... so they were tight in their previous (original/OEM) state.

I'm thinking of ripping the bike apart tonight after work and tightening them up a tiny bit to see if this makes a difference(basically putting them back to where they were before).... which would be tighter than spec.

A few other guys that I know mentioned that they basically set their valves by hand rather than using the feeler gauges to measure the clearance... or that they set one real accurately with the gauge and then adjust the rest by feel based on how much wiggle there is in the valve, rather than using the feeler gauge for each one.

Do most of you just go with the feeler gauges? Do any of you run your valves slightly tighter than spec?

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I'm thinking of ripping the bike apart tonight after work and tightening them up a tiny bit

lol thats ripping the bike apart? hehe

But seriously no i use feeler guages and adjust them to spec (well actualy i use my dads coz i dont want to bend mine, dont tell him :))

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I've been known to use the jiggle method on more than one occasion. Usually on someones junk motor that I can't find a spec for anyways.

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everytime I adjust my valves on my 650L ( with the feeler gauge ) it seems "harder to start" to me afterwards.

The last time I reset the idle speed after the adjustment and that seemed to help. Not sure how those are related, maybe it's all in our heads that they are harder to start after the valve adjustment.

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You should be able to adjust them by feel with great results if you know the thread pitch and do a simple calculation to determine what fraction of a turn you have to back it out after you turn it in and make light contact. That said, I use a feeler gauge for mine.

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I use a feeler gauge every time. I used to do it by dragging the feeler back and forth feeling for a little drag. Well one time I swear I adjusted it correctly 3 times in a row but each time I was way loose. (bike started ok but sounded horrible. I eventually used the go-no-go method.

Go-no-go method:

If the upper end of the spec is .003 then set the clearance using a .002" or .003" feeler. THEN try a .004" feeler, it shouldn't fit. if it does your too loose. Bingo! It has to be dead nuts on. This helps take the subjectivity out of it.

Turns out because of the tight space to access the tappets I was getting a false reading because of the bend I had to put in the feeler to get it under the tappet.

I've really only had to adjust valves on rare occasions. Usually I just confirm that they are in spec. I adjust when I buy a bike or do top end work (big bore, new gaskets, etc.)

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By feel, not me. I'm good, but not THAT good.:) Got to use the feeler gauge. I never adjust mine to the tight end of the spec. I more or less use the Go-No Go method. Sometimes it can be tought to get it just right, then go to tighten it down with the jam nut while trying to hold the screw stationary. If when I go recheck it and a .004 goes, but difficult, close enough.

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everytime I adjust my valves on my 650L ( with the feeler gauge ) it seems "harder to start" to me afterwards.

I've always found this too with my 400. I use a set of "custom" feeler guages that have the tips bent at ~60 degrees. OTOH, my XR400 is a nightmare to start anyway - drove me to buy an e-start 250X even.

Interestingly, I recently did some engine-out frame work. While the engine was out on my bench, I did a valve adjustment. Since I could get into everywhere, I was able to actually get the adjustment perfect with the motor up on a bench. Now it starts first kick. Go figure. I maintain that between the tucked-in position of the valve and the tight access to the valve covers, not to mention the course threaded adjustment screw (that REALLY irritates me) it is virtually impossible to properly adjust the valves, regardless of the tools used.

JayC

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I think not using the feeler gauge correctly is the problem for most people.

Here's the right way to do it IMO . With the bike stone cold for at least 24 hrs... best to use a feeler gauge that is about 1/4 inch wide. With the piston inthe correct position, Loosen the lock nut and back off the adustment till you get the feeler gauge in the right position. Move the feeler gauge back and forth while screwing the adjuster down till it pinches the gauge somewhat and you cant move the gauge any more. Then very slowly back off till the gauge is released and you can JUST slide it out. Stop. Lock it down there.

BAsically, ovetightening a little and backing off is a more acurate way .

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I just redid my valves today, and went tighter than I usually do... sorta like the way they were when I first got the bike. It starts up much much better now and the valves are a lot quieter.

Something to keep in mind for the rest of you who have noisy valves or hard starting despite the valves being set to "factory spec".

When i rode it around my yard, it had quite a bit more power than before too... so this is apparently the way the valves are supposed to be set, and my prior valve settings must have been too loose and leaking.

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...and my prior valve settings must have been too loose and leaking.

just a note.... loose valve adjustment (greater distance between adjustment screw and valve) would be tight valves. That extra distance in your adjustment is used by the screw pushing against nothing longer and opening the valve less.

Loose valves are when your adjustment is too tight and the valves open further and for a longer period of time.

Just to keep everyone on the right page when asking questions.:)

-John

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Airborne2007 is correct. if your tappits were loose that would mean the valve opening less wich would give it less gass. it seems logical that a tighter setting would push the valve open further and give it more power. a loose tappit would not cause the valve to leak, but it would give the engine a little less gass. IMO i would rather have my tappits a little bit tight rather then a little bit loose

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