1. Dismiss Notice
  2. Hey Facebook people... We've created a group for XS400.com members to connect. Check it out!
    Dismiss Notice
  3. Want an XS400.com t-shirt? Go to the store to order. Limited sizes and quantities available.
    Dismiss Notice

Valve Adjustment Confirmation

Discussion in 'The Garage' started by kevingkruse, Oct 24, 2012.

  1. kevingkruse

    kevingkruse XS400 Addict

    Ok, I was always confused on adjusting my valves, so after reading all the threads on it, I tried it for the first time. I adjusted all valves, .004 intake, and .007 exhaust, and my bike starts and seems ok but I want to tell you how I did it and see if I did it wrong or right. So I turned the alternator around, with my finger on the right spark plug hole, and waited untill I felt it compressing (pushing my finger off) and stopped on the RT line then adjusted the right exhaust valve, then I turned the alternator half a rotation and stopped on the LT line, then adjusted the intake valve. Then I did the same for the left side. Am I doing it right? Or did I do it backwards? Can you only adjust the valves one way? I mainly want to ask because I don't hear that much or any noise in my rocker arms, or maybe I don't have the ear for it... Thank you very much for any info.
     
  2. xschris

    xschris a lifestyle not a trend

    You should do the left side first then right. Just make sure that you always turn the engine forward never back to hit the mark it will throw off the valves.
     
    buztabuzt likes this.
  3. Enjine

    Enjine XS400 Member

    12
    0
    1
    ~
    So you do need to turn the engine a half a rotation prior to checking the exhaust valve?
     
  4. xschris

    xschris a lifestyle not a trend

    No at TDC both valves are closed that is when you set them both. The LT mark is when the left piston is at TDC and RT is when the right is at TDC.
     
  5. Enjine

    Enjine XS400 Member

    12
    0
    1
    ~
    That's what I thought, thanks for the clarification.
     
  6. Tombo

    Tombo XS400 Addict

    Enjine - the LT mark does mark top dead center.... EVERY OTHER rotation. It is important that you know when the bike is actually approaching top dead center and not - otherwise you will set valve clearances WAY too loose (it happened to me my first time).

    So how will you know? While rotating the motor with the plugs out, place your thumb over the left hand spark plug hole and make a seal with the pad of your thumb. Rotate until you are starting to feel pressure build up - now slow down and watch for the LT mark. Make sure you land RIGHT ON the LT mark, and then brace your wrench somehow, as the motor will want to continue to push your wrench counter clockwise. I personally use a long handle ratchet and let the handle rest against the shift lever while I make my adjustments.

    Follow this info and you will do it right the first time. It's actually pretty easy.
     
  7. 226dark

    226dark 78 2E

    I did this past weekend. I don't know if there is any backwards but by manual (and from memory) you do the left side (both intake and exhaust) while at LT mark. It says you will feel rocker play if at TDC on compression and both valves closed but I didn't notice that. Then both adjust caps back on the left side, do the right side. Again, by memory ( and I have 1978 2-e) intake is .003 - .005, exhaust clearance is .006 - .008 - i think.
     
  8. kevingkruse

    kevingkruse XS400 Addict

    Great, well I think this should clarify this subject a little more for noobs like me... so what I did wrong is that half rotation after exhaust to do the intake, and not starting on the left. Thank you very much!
     
  9. Also check this site for the free factory service manual. Sooooo helpful.
     
  10. mattg666

    mattg666 XS400 Enthusiast

    Ok, bringing this one out, I have the left intake valve adjusted... But to do the left exhaust do I still leave it at the mark for left top? Because it being there, the exhaust one is just too far down for me to be able to check it...please help

    Posted via Mobile
     
  11. mattg666

    mattg666 XS400 Enthusiast

    Yes I bent my feeler gauge to try to fit but it gets down in there but it just won't get under the screw and it's backed almost all the way out...... Soooooo how do I adjust that valve?

    Posted via Mobile
     
  12. xschris

    xschris a lifestyle not a trend

    Your not at tdc then if the other is off that far. Check the manual again and start over:wink2:
     
  13. mattg666

    mattg666 XS400 Enthusiast

    Uhh yeah I've read the manual and it gives about the vaguest description on how to do it. But I I'm dead center on the line right next to LT... And never back pedaled on spinning it. And people are saying that you have to do both at LT and I can't get the exhaust... So then please someone go into more depth as to what placement it has to be in exactly in order to do it? Because I'm following all the information in the manual and if it's not right then I don't know what else to do...
     
  14. mattg666

    mattg666 XS400 Enthusiast

    Is TDC on the line directly to the left of the LT markings? Or??? Nowhere explains it, but I'm assuming that the line right to the left of TL is TDC considering that's the only line there...
     
  15. xschris

    xschris a lifestyle not a trend

    Your 180 degrees off. The wheel will turn twice for every cycle of each piston. When you spin it ( with the plugs out) when you get tdc on the piston both valves should be a bit loose. If one is tight and the other is loose then it is 180 off. If you are at tdc the wrench will want to spin back. Don't let that happen or it will put slack in the cam chain giving you a bad adjustment. Use a strap or a friend to hold it in place when you hit it.
     
    buztabuzt likes this.
  16. mattg666

    mattg666 XS400 Enthusiast

    Awesome thanks for clearing that up!
     
  17. mattg666

    mattg666 XS400 Enthusiast

    Ok tried it, and now my intake one is in the same position that my exhaust was in... And I triple checked that the cycle I was on was the correct one... I have the intake backed almost all the way out and still too far down in... This is frustrating as all fuck
     
  18. xschris

    xschris a lifestyle not a trend

    Watch the rockers. When your at tdc they WON'T move. That is your compression stroke. If your adjusters are way off from your previous "adjustment" you can try and turn them in to where the right side is as a reference to go by.
     
    buztabuzt likes this.

Share This Page