Valve Job

[spizzak]

Hey everyone, I'm just finishing up my valve job and I noticed something strange. I replaced 5 shims that were out of spec, but the clearance for 2 of them (same valve exhaust side) stayed the same. The others are all in spec now but these to stayed at around 0.015". Anyone know why this might be?

[95FZR600]

Not all valves change. Some can stay and some can change. Thats just they way it goes.

I did the valves at school last week on a 02 R6 and I had two valves remain the same as well.

[spizzak]

So.. i just leave it? Can I do anything to fix that?

[95FZR600]

What is spec for that one?

[spizzak]

Specs: Exhaust (0.008~0.012”)

2 Valves: 0.014 & 0.015"

[95FZR600]

Specs: Exhaust (0.008~0.012”)

2 Valves: 0.014 & 0.015"

You need to shim them and add 1.0 to the shim that was in there.

For every thousanths you need to add .05

[spizzak]

I'm not sure what you mean. Could you explain in a bit more detail? I believe I have 160 shims in there right now.

[95FZR600]

I'm not sure what you mean. Could you explain in a bit more detail? I believe I have 160 shims in there right now.

ok,

Specs: Exhaust (0.008~0.012”)

2 Valves: 0.014 & 0.015"

You need to bring the .014 down to .008--------thats a .006 difference. You need to add .05 per every .002 = 1.5 added to your 160 shim = 161.5

[spizzak]

okay I got you, but 0.05 x 3 = 0.15 not 1.5 .. I'm not sure if one of those is a mistake. So basically I have to re-readjust the shim? Do you know why it didn't do anything the first time I did that?

[slayermd]

This may help.
http://www.logicminds.biz/motorcycles/shimulator.html

[DonTZ125]

The shims are in mm, numbered in 100ths of a mm; a #160 shim = 1.60mm. You're measuring in inches. Convert your clearance to mm (in * 25.4 = mm), do the math, determine the new shim size.

.014" - .012" = .003"
.003" * 25.4 = .076 mm increase in shim thickness = +7.6 shim number. Shims are in 0.05 mm / 5# increments, so go up 10#. In this case, from #160 to #170.

I've been told by many that it's better to run the clearances loose. You get a better valve seal = better power, and the clearances last longer between necessary adjustments. That's why in the example above I based it on the .012" / 0.30 mm max clearance, not the tighter 0.008" / 0.21 mm min clearance.

Good luck!

[95FZR600]

okay I got you, but 0.05 x 3 = 0.15 not 1.5 .. I'm not sure if one of those is a mistake. So basically I have to re-readjust the shim? Do you know why it didn't do anything the first time I did that?

Your right .015

I was on the phone and writing. LOL That could have been ugly.

[95FZR600]

The shims are in mm, numbered in 100ths of a mm; a #160 shim = 1.60mm. You're measuring in inches. Convert your clearance to mm (in * 25.4 = mm), do the math, determine the new shim size.

.014" - .012" = .003"
.003" * 25.4 = .076 mm increase in shim thickness = +7.6 shim number. Shims are in 0.05 mm / 5# increments, so go up 10#. In this case, from #160 to #170.

I've been told by many that it's better to run the clearances loose. You get a better valve seal = better power, and the clearances last longer between necessary adjustments. That's why in the example above I based it on the .012" / 0.30 mm max clearance, not the tighter 0.008" / 0.21 mm min clearance.

Good luck!

People bring their bikes in because the valves chatter. Thats because of the clearance. I was told to bring them down to spec to tighten the clearance and no more noise. You may be right about the loose clearance - better valve seal. I believe that. As long its within spec though.

[DonTZ125]

Absolutely - as loose as the spec allows, but no more.