• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Low RPM Vibration: valve/cam vs piston/cylinder clearance

  • Thread starter Thread starter Joe Garfield
  • Start date Start date
J

Joe Garfield

Guest
My bike has a lot of low RPM vibration, most of which smooths out at higher revs. The carbs were rebuilt, valve buckets adjusted, and carbs properly synchronized.

I'm in the middle of a top-end refresh:
  • I checked the valve clearances and found that #1 exhaust had less clearance than my smallest shim, all the rest were between .06-.08mm. My hunch is that we mis-adjusted #1 exhaust, but I guess it's possible it wore down that much?
  • I measured the piston:cylinder clearance per the manual. It's exactly at the service limit for clearance, and the pistons are exactly at the service limit for 'diameter'. Of course, this is before the cylinders get honed

I'm trying to decide if I should get a new set of pistons or not. It's hard to say if the vibration is caused by the piston wear or the mal-adjusted valve, but I recently read a review about another Suzuki bike which suffers from low RPM vibration due to the pistons 'leaning'. Of course I don't want to open the engine again, so I'm wondering if I should replace the pistons or not. I know it will be 'fine' if I leave them alone, but the vibration is annoying to me, and certainly won't help if I decide to sell the bike.

(Edit: Of course, this thinking was when there was a NOS piston set on Ebay for $100, which I should have bought :( )

What do you think?
 
Last edited:
You must log in or register to reply here.
Back
Top