How do I know which shims go where?

[humblepie]

on the bucket.Please help.

[Nessism]

Adjusting shims sit into a recess on top the valve bucket. Don't mean to sound harsh but you need to sit down and read the manual. If you don't have one, get one before going any further.

[humblepie]

i have one,I just don't know which shims should go on which valves


the shims i have are three-2.70
one-2.70x
two 2.75
one-2.80
one-2.65

[Clone]

Well, in no specific order, 2-5-4-6-1-3-8-7
](*,)

Do you know the purpose of the shims?
They are of diffent thicknesses, because you need to measure the space left after you put them in the buckets to get your proper clearance.

[humblepie]

I dont have feeler gauges can I adjust it by trial and error?

[earlfor]

There is no set shim thickness for valve adjustment.
It is not possible to shim the valves correctly without proper feeler guages because you must know what the original clearance was to be able to calculate the difference between that and what it should be. Then you must replace each shim with a new one that has that correct thickness difference to arrive at the correct clearance between the shim and cam lobe. Before you go any further, you need to get a book and read the proceedure as many times as it takes until you are certain you understand it. There is zero possibility you will get it right by luck.

Earl

I dont have feeler gauges can I adjust it by trial and error?

[humblepie]

okay I understand it completely.Just curious,what happens if it's not within those tolerances?

[earlfor]

Most likely, it will not run, but if it does run, it will run very poorly.

Earl

okay I understand it completely.Just curious,what happens if it's not within those tolerances?

[Nessism]

Most likely, it will not run, but if it does run, it will run very poorly.

If the clearance is too much the shim can spit out thus leading to cam and bucket destruction. If there is not enough clearance the valves will not close all the way which will result in burned valves.

[chef1366]

It's better to hear them than smell them.

[Pharkmeh]

It's better to hear them than smell them.

funny - my missus says the same thing...:shock:

oops soz - tech thread... - my bad...

[BassCliff]

It's easier with pictures

Mr. humblepie,

Get yourself some feeler gauges, the metric kind that go down to at least .04mm. The clearances between the bottom of the (properly rotated) cam lobe and the top of the shim should be between .03mm - .08mm. It's a little tougher using ASE (US inches) feeler gauges. Depending on your gauge set, you may not get all the fine measurements you need.

There is a valve adjustment procedure with pictures in PDF format at:

http://www.dslextreme.com/users/bikecliff/

You'll have to measure the clearances, check the shim thicknesses and then do a little math to replace the shims with thicknesses that put the clearances within spec. If your clearance is too tight, usually going down one size will bring you back into spec (i.e. replacing a 2.70 with a 2.65).

Thank you for your indulgence,

BassCliff

[humblepie]

Thank you BassCliff,Nessiem pointed me to your thread and it's a big help..it should be a sticky.

[Steve]

If you would like a little help keeping track of which shims you need for your valve adjustment, send me an e-mail. I will respond with an Excel spreadsheet as an attachment that will help you keep track of your valve adjustments.


.

[bwringer]

A set of metric feeler gauges is about $5 at any auto parts store.

If you don't have $5 to spare, you have no business fooling with old motorycles. Get a(nother) job! :-D

You don't need a lot of money, but geez, you need to invest a little.

The proper shim tool is less than $20 from Z1 Enterprises, CRC2, or Dennis Kirk. Shims are about $5 each if you need different sizes.

Manuals are about $20 - $25 each at http://repairmanuals.com .