Valve clearance issues

[Padmei]

I have measured my valve clearances on my 08 KLR650 (18000kms) & found one intake right on the minimum spec & one intake I couldn't even get a feeler guage under. If I get the thinnest shim available from the local Kawa dealer the valve clearance still won't be within specs.

Whats the long term issue with this & how should I go about this?

FYI the specs are 1.0-2.0 mm & one intake is 1.02mm & the other is 0.00

The shims at the mo are 2.55 & the smalest kawa one available is 2.00

Any help appreciated

[tri boy]

Valve seat/valve wear, stretch. Get it seen to. MHO

[Woodman]

Valve seat/valve wear, stretch. Get it seen to. MHO

What he said. You could find thinner shims or get yours machined, but the tight clearances may be the symptom rather than the cause.
Of course it is possible thats how gonzo was made.

Edit, hang on are you sure you are reading the clearances correctly? If the shims you have now are 2.55mm and the smallest is 2mm then that is .55 mm which in proper language is about .022" (imperial) which should be heaps. They go in .002" jumps.

I will return.

edit again . me thinks you got decimal point in wrong place. You need a 2.5 mm shim and a 2.4mm shim to get the clarances to spec if what you say is correct.

Sorry for all the edits

[Padmei]

Thanks for the reply.
I thought my measurement didn't sound right.

OK just to confirm. The intake specs are 0.10mm to 0.20mm

left hand side measurement is 0.00 & right hand side is 0.102mm

Current LHS shim has 255 stamped on it & RHS is 255. I thought the ....

Ahhhhh Fcuk ....:slap: Finally understand

[pete376403]

BMW K bike shims fit KLRs and are reputedly cheaper.

[LBD]

right hand side is 0.102mm

Not sure you have it right yet.....Metric feelers do not read to 3 decimal places....sure you are not looking at 0.000" (thousands of an inch)

And if when cold you measure 0.00 clearance...as the engine warms, the valve gets hotter and longer and would not seal on the valve seat....you would likely have backfiring through the inlet.

[CookMySock]

And if when cold you measure 0.00 clearance...as the engine warms, the valve gets hotter and longer and would not seal on the valve seat....you would likely have backfiring through the inlet.

When this happens on smaller (250-400cc) inline fours, will they not idle well at all when warm?

Steve

[MotoKuzzi]

If both shims are the same but one valve is zero clearance wouldn't that suggest valve seat recession?

[LBD]

When this happens on smaller (250-400cc) inline fours, will they not idle well at all when warm?

Steve

you would find it pretty much with any engine....valve clearance is to allow the valve to seat when hot

Likely a sign of valve face/vale seat wear.

[Padmei]

Not sure you have it right yet.....Metric feelers do not read to 3 decimal places....sure you are not looking at 0.000" (thousands of an inch)

And if when cold you measure 0.00 clearance...as the engine warms, the valve gets hotter and longer and would not seal on the valve seat....you would likely have backfiring through the inlet.

Nope the feeler guages read 0.004 & underneath 0.102mm.
Thanks I will get the right shims tomm.

[quickbuck]

If both shims are the same but one valve is zero clearance wouldn't that suggest valve seat recession?

Either Valve Seat Recession, OR Valve stem growth.

[kwaka_crasher]

Not sure you have it right yet.....Metric feelers do not read to 3 decimal places....sure you are not looking at 0.000" (thousands of an inch)

1.02mm is 0.040"... or 40 thou (thousands of an inch). The feelers he's using are imperial but also marked in metric.

[FROSTY:Me]

To be honest I feel if those are ya clearances then the bikes gonna be pretty sickly.I'd suggest you hand crasnk the engine over again and recheck.

[CookMySock]

the tight clearances may be the symptom rather than the cause.

This happened to me. One tight valve, and "noisy tappet" sound. I pulled the cam out, removed the bucket, and found the collets just about to let go.

Lucky I caught it.

Steve