Valve adjustment

1980 xs650special

XS650 Member
Messages
20
Reaction score
0
Points
1
I'm a newby at some of the engine adjustments but can anyone explain in detail how to adjust the valves on a stock '80 xs to the right tolerances?
 
I used that, ended up with my valves wide open. There is a youtube video that in conjuction with the manual is more useful


holy fuck you guys, not rocket science.


Put motor to TDC using the marks on the stator/rotor, pull exhaust/intake and tappet cover off of one side or all of them for all i care....one side should have wiggle up and down on both intake and exhaust tappets (other will be tight) which means that cyl is a TDC on the comp. stroke. Use your feeler guages to set .004 on the intake and .006 on exhaust if memory serves me correct. Rotate engine 360* and do the other side.

If any of this confuses you time to buy a new bike and have your dealer look after you. The manual is very easy to follow to set valves...all i have is a clymer.

and these are set cold....not warm...cold, like sitting over night.
 
So, if the tappets wiggle a little bit, enough to notice, that means they wiggle MORE that .006 or .004.

Where do you adjust them to, the widest the gap gets, or where they rest?
 
So, if the tappets wiggle a little bit, enough to notice, that means they wiggle MORE that .006 or .004.

Where do you adjust them to, the widest the gap gets, or where they rest?

They will wiggle ever so slightly at TDC of the ones you are checking because there is no pressure on them from the cam. Both valves are closed for the compression stroke meaning everything is at rest.. the other side is on an exhaust stoke so the valves are tight/exhaust valve is being pushed on...you can see that. You can feel that .004 and .006 although minute.

when starting from scratch after a rebuild you will have to watch for the exhaust valve being pushed on to figure out which side as all of your tappets should be backed right off for reinstall of the rocker box.

maybe you don't understand the feeler guage part of it. Will a .004 guage slide in to the little gap between the tappet and the valve stem on that side (intake) at tdc....if not then they are tight..if a anything bigger fits in then they are loose.......back the lock nut off and back the tappet off till a .004 guage will fit in...hold tappet with little wrench...tighten lock nut to hold that setting. done.
 
i did understand it, but at the time i was using an adjustable wrench rather than the tappet wrench and to find TDC i used a penlight and looked through the spark plug hole... so, when re tightening the locknut the tappet was moving with it and with the adjustable wrench, it was hard to hold on to the little tip.

I did go out this moring and take a looking using the T mark and the tappet wrench, and it seemed to go alot smoother. Though i'm still getting that rattle! I guess it is just the lud tappets. My cam was set at flush at TDC on a warm engine, i don't know what else i can do...
 
nah, i meant after i started it. It is making the metal rattle sound. A lot of people say, "adjust your cam and your valves and it will go away". Many others say, "they all sound like that"

I will double check my clearances, though they all seemed good: Could slide the feelers in with a tiny bit of resistance?
 
That's how you're supposed to use them. They don't call them "feeler" gauges for nothing, lol. They're supposed to slip in and out with a slight drag when clearance is correct. And if you had a manual, why would you try to find TDC with a flashlight through the plug hole?
 
I wasnt looking hard enough at the rotor when i was rotating the engine and couldn't find the T mark. at the time, i was just googling, and one of the intructional sites mentioned that not all rotors had the T mark. this of course was only days after i bought the bike. As I said, i learned from my mistake, i'm a Environmental studies student with little background in mechanics. Only one way to start, right?
 
I would have guessed English Major but I suppose environmental studies is today's equivalent. :wink2:
 
Cmattina1, I've gotta say that I admire you for doing this and working to figure it out. So many of us assume that things are easy when we know all about them (like when I ask my kids to help with my iPhone or computer...they know so much more than I do!). Anyway, good luck and best wishes, and please keep asking and looking. What you say makes sense, and if you've never used feeler gauges before I understand why you may be having difficulty. Especially in a little, crowded area like that for your first time with feelers. Keep asking, keep us posted on your activities and progress. I, for one, am THRILLED with someone apparently your age getting into these and making a go of it.
 
Environmental studies may be today's english equivilent indeed, my friends and I joke about it all the time. To boot, my undergrad is "Outdoor Recreation" and my masters is actually environmental studies! I get a lot of flak from my dad who is a millwright. Regardless, I got it all done today and I didn't screw anything up! As I said before, i just wasn't putting a fine enough touch on things with the adjustable: Thank god the bike came with a complete yamaha tool kit.
 
Environmental studies may be today's english equivilent indeed, my friends and I joke about it all the time. To boot, my undergrad is "Outdoor Recreation" and my masters is actually environmental studies! I get a lot of flak from my dad who is a millwright. Regardless, I got it all done today and I didn't screw anything up! As I said before, i just wasn't putting a fine enough touch on things with the adjustable: Thank god the bike came with a complete yamaha tool kit.

My home town of Thunder Bay! As I was reading, I was think to myself - "at least he's not an outdoor reccer" LOL

Welcome to the board, lot's to learn here:D
 
I did not get along with the majority of the people in my classes. Luckily i get compliments from many on how i am the "first outdoor reccer i get along with". Being from downtown hamilton helps in not being one of those suburban tree huggers ;)
 
Intake .004? Clymer says .0025 I know that they varied it in early years but mine is a 1980 G model. Clarification so I don't beat the hell out of things on a fresh complete over haul. The shop that did the heads wrote .004 intake and .006 exhaust
 
Back
Top