valve shims... Help..

[El Bruto]

Ok.. so some of you guys will know I've been plodding through re-building my engine.. and I'm almost there...

So head is now back on, but as I had a slight leakage on a couple of valves I decided to send the head away to have all the valves done... Well it seems they have re-cut all the valve seats, which now means that nearly all of the valves do not have enough clearance.. ..

So this is my dilemma... as there is no clearance, how the hell do I work out what size shims I need to order.. I'm guessing the standard shims are about 2.75mm .. and I know they sell shims from 2mm to 3.2mm.. So I'm pretty confident its not a total wipeout.. but as I don't know if the spring is still compressed, how can I work out what's needed...

In my head, ive thought of getting 1 x 2mm shim.. and then placing that in each bucket and working out how much bigger is needed from that... I've tried removing the shim completely and measuring from the bucket.. but you cant get feeler gauges in there... .. any other answers?

 

[TURBO200R4]

just a thought
u might run a compression check
if compression is good u would know they are closed.
warp would be the one to ask.

 

[TURBO200R4]

i always thought that when they seated them they would take an equal amount off the top of the valve but that is probably wrong.

 

[El Bruto]

don't want to rebuild the motor completely and then strip it down again, motor is out at present and would prefer to have it all correct before it goes back in.. as some of them have zero clearance when cold, I'm sure that will not make for good valve clearances when hot...

Its been a long painful road for me rebuilding this so very keen to make sure its good.. cant afford to have engine out for a 3rd time.

 

[R-III-R Turbo]

if i was you i'd buy a selection box of shims from the local bike shop. then when you have cams in and chain tensioned you can valve clearance and adjust as necessary. unless you know how much meat they took off the valve seat you'll have a hard time getting shims right the first time. with the valves closed and no cams in you could try use a calipers to get an approximate distance from valve stem head to the underside of the cam lobe and subtract required clearance + bucket face thickness to start with

if you wanted to do a compression check you'd have to run the engine which wouldnt be a good idea with out of spec valve clearances. however with just the head on you could do a leakdown test instead via the spark plug hole. but at this stage my understanding is that you are past testing for leaks and just want to get valve clearances right?

 

[El Bruto]

yep.. had the head vacuum checked.. all valves nicely seated.. all I need do now is sort the clearances.. but no triumph dealer nearby, and the shims come in loads of different sizes.. so cant order all the options as it would cost thousands.. they are 10euro each, times 12 valves and there are about 15 differednt sizes.. so not an option,.. a 50 cent coin is similar diameter, and around 2mm.. so was thinking of checking it with a micrometer,, then using that as a base .. 2mm plus whatever,

 

[Bedifferent]

I think I can help with this...here are a couple of charts I found that tell you what shims you need based on the clearance you have and what clearance you desire for intake and exhaust valves. The instructions are given on the charts. One chart is for the intake valves and the other is based on the exhaust valves. Regardless of what your clearance is suppose to be, these charts should help you choose the correct shim. Good luck!

 

[TURBO200R4]

i have never done this
i would take two feeler gauges that add up to 0.080 inches that equals 2.032 mm
i would cut them to fit them i would measure the difference in inches and then change that into mm.
the changes in the shims is .025 mm equals .001 inches.
inlet .0039 to .0059 inches 4to 6 thousands.
exhaust .0059 to .0079 inches 6 to 8 thousands
some times i have good ideas and some times they turn to (well u know)

 

[kipper]

I think your idea was right 1 2mm shim and use that to get your measurement. The charts Bedifferent posted look very useful.

 

[mport]

If your valve job was done correctly, the same amount removed from the valve seat should have been removed from the stem. This practice will eliminate valve clearance issues.