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Main Area => General GS500 Discussion => Topic started by: deck95gs500e on November 24, 2003, 08:05:28 AM

Title: Shims size needed???
Post by: deck95gs500e on November 24, 2003, 08:05:28 AM
Hi all,
     I will have a mechanic come over which is highly recommended at BARF  to work on my valve clerance adjustment and wondering what size of shims I need so that I can find out if my local suzuki dealership have them in stock.  Should i have him do a carb sync also after he adjusted the valve?  should I change my plugs too?  I just change the oil/air filter last month and since I will have a mechanic around im wondering what else I need to have check on my bike maybe compression check? any thing I have to be aware of when he's doing the valve adjustment ?

thanks,
Derick
Title: Shim...
Post by: The Buddha on November 24, 2003, 10:43:26 AM
Shim's are the same diameter but different thicknesses... You cant buy some random ones... also 4 shims only... dont leave much room for swapping... However find what shims you have, and get ~10 in that range... and you should be OK... and buy suzuki shims only, yamaha and kawi shims are smaller in dia nd will fit in a pinch... but they are more likely to fly off... But the mechanic should have some in his cache.
Cool.
Srinath.
Title: Shims size needed???
Post by: Kerry on November 24, 2003, 10:44:02 AM
Unfortunately, the only way to know what shim sizes you need is to perform a valve clearance check.  For each valve you need to know 1) the current amount of clearance, and 2) the thickness of the current shim.  You select a new shim thickness that will give you the desired clearance of .03 mm to .08 mm.

You measure the amount of clearance using a set of blade-style feeler gauges.  If you're lucky you can find a set with the thinnest blade close to .03 mm in thickness.  (In my set, the thinnest blade is around .04 mm thick ... so until I sand the other end of it down I have to guess.)

You measure the thickness of the surrent shim with a micrometer or a set of dial calipers.  Then you do the math or use the chart below to figure out the thickness you need for the replacement shim.

See these images that I scanned from my Haynes manual:

Measuring Shim Thickness (http://www.bbburma.net/Scans/Haynes_HomemadeValveShimTool_Use.jpg)
Shim Selection Chart (http://www.bbburma.net/Scans/Haynes_ShimSelectionChart.jpg)

EDIT: Changed links from sisna.com to bbburma.net