Author Topic: Valve Adjustment question - How do you get a feeler gauge in there?  (Read 3743 times)

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Offline jkot55

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Re: Valve Adjustment question - How do you get a feeler gauge in there?
« Reply #25 on: March 30, 2010, 08:32:42 AM »
O.K.  That's what I was doing, just found it time consuming (which I do not mind as long as there is a benefit) so that's why I was wondering about the tolerence. I'll see when I recheck them.

One quirk I found in the manual (among many actually) is that in getting to the starting point it says to look for the 1-int to retract then start to rise.  I believe they got it backwards.  You want to see 1-int rise then start to retract.  (e.g. at it's hishest point as viewing it through the hole with the cap off.  It's at this point you can allign the "T" mark.  This is the position where I found it posible to get the .002 feeler in the gap. 

Speaking of caps.  I want to replace the o-rings (about 28mm round)  I am going to look in Home Depot or a hardware store for them rather then go to the dealer.  I am sure the dealer will want $2.50 a piece where I can get a package for just a few bucks and more convenient.    Have any of you found them this way?
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Offline Duke McDukiedook

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Re: Valve Adjustment question - How do you get a feeler gauge in there?
« Reply #26 on: March 30, 2010, 08:37:39 AM »
If you can wiggle it back and forth with your fingers and the opposing is tight, that is one way to tell if it is at TDC.
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Offline MCRider

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Re: Valve Adjustment question - How do you get a feeler gauge in there?
« Reply #27 on: March 30, 2010, 08:52:02 AM »
O.K.  That's what I was doing, just found it time consuming (which I do not mind as long as there is a benefit) so that's why I was wondering about the tolerence. I'll see when I recheck them.

One quirk I found in the manual (among many actually) is that in getting to the starting point it says to look for the 1-int to retract then start to rise.  I believe they got it backwards.  You want to see 1-int rise then start to retract.  (e.g. at it's hishest point as viewing it through the hole with the cap off.  It's at this point you can allign the "T" mark.  This is the position where I found it posible to get the .002 feeler in the gap. 

Speaking of caps.  I want to replace the o-rings (about 28mm round)  I am going to look in Home Depot or a hardware store for them rather then go to the dealer.  I am sure the dealer will want $2.50 a piece where I can get a package for just a few bucks and more convenient.    Have any of you found them this way?
The manual is right. The #1 intake goes down all the way (retract) then starts to rise. At that point you look for the T. If you wait for it to begin to retract again, it will have gone too far and you'll have to back the motor up. Not the end of the world, but the idea is to never back the motor up.

It may just be an interpretation issue, but your recall of the manual is correct, and the manual is correct.

I tend to have lots of inspection cap Orings left over from broken gasket sets. Never bot one from the hardware, but should be OK. A tip, don't crank the inspection cap down hard. They should be hand tight, then 1/8 to 1/4 turn to set the Oring. Run it and if one seeps, tighten it a bit more.

There are many threads here about people who have broken caps or stripped the heads because they were on too tight.
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Offline bistromath

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Re: Valve Adjustment question - How do you get a feeler gauge in there?
« Reply #28 on: March 30, 2010, 09:09:57 AM »
Here's how to adjust the valves perfectly without overshooting:

Get it close by gently closing the adjuster with a 0.001" oversize feeler in there. For the intake, use 0.003". Then tighten the nut and remove the feeler. You'll be fairly close at this point. Use the correct size feeler to judge the gap.

If it needs more gap: Loosen the nut a LITTLE BIT while holding counterclockwise pressure on the adjuster screw. This way, the screw will move as the nut turns out, but only as far as the nut turns. Then lock the nut back down while holding counterclockwise pressure on the adjuster screw. The adjuster screw won't move.

If it needs less gap: Loosen the nut a LITTLE BIT while holding clockwise pressure on the adjuster screw. Then tighten the nut down again, while holding clockwise pressure on the adjuster screw. This will tighten the screw just as much as the nut is tightened.

Repeat until you've got it set. It sounds complicated but it makes things very exact, and it's easy when you get the hang of it.
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Offline jkot55

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Re: Valve Adjustment question - How do you get a feeler gauge in there?
« Reply #29 on: April 03, 2010, 05:34:53 AM »
Just want to thank all you guys for your help.  I could not have done the valve adjustments without all of you.   All of your advise was right on the money.   It runs really good now.     :)
When I ride my CB750 I'm a teenager again