Valves clearances

[Shane4371]

OK fellas #2 cylinder .006 is virtually impossible to get my feeler gauge in .004 is very tight the same on #4 cylinder.please advise.

[Shane4371]

OK fellas #2 cylinder .006 is virtually impossible to get my feeler gauge in .004 is very tight the same on #4 cylinder.please advise.

this is intake side

[FJmonkey]

I am going to assume your numbers are in inches. .006 x 25.4 = .1524 mm. For intake the minimum gap is .11 mm, nominal is .13 mm and max is .15 mm. So your gap is a tad big. Measure the current shim and then install another shim that is .01 to .04 mm thicker. If your number .006 is in mm then you are super tight. Again measure the current shim, do the math to find a thinner shim that get a proper gap.

[fj1289]

Shane,

I like the "GO", "NO GO" technique for checking/setting valve clearances.

If you are using inches, and for the INTAKE valves, get your feeler gauges for .007", .006", .005", .004" and smaller.


Try the .006" first - it should "GO", but may have some resistance.
Try the .007" - it should not go -- i.e. "NO GO"
If so, the clearance is Good.


IF .006" is a "NO GO" - then try .004". 
If .004" is a "GO" then decrease the valve shim by one "size".  "Standard" valve shim sizes are in 5's -- such as 250, 255, 260, 265, 270, 275, etc. 
But, if .004" is also a "NO GO" (or is very difficult to slide in) -- then decrease 2 shim sizes.  For example, it is a 270 -- then go down 2 sizes to 260. 

After you change your shims DO NOT remeasure your clearance (I got schooled on this recently!).  You MUST get the engine up to operating temp AND LET IT COOL OVERNIGHT to be able to check your work.  If you try to remeasure your clearance after swapping a shim without running up to temp you WILL bet a BAD measurement and will then swap to a WRONG shim. 

For the EXHAUST side you are looking for a "GO" at .008" and a "NO GO" at .009. 

The golden rule on valve clearances is too much is a LOT BETTER than too little!

[Shane4371]

When I get off work I'll recheck thanks so much

[Shane4371]

Shane,

I like the "GO", "NO GO" technique for checking/setting valve clearances.

If you are using inches, and for the INTAKE valves, get your feeler gauges for .007", .006", .005", .004" and smaller.


Try the .006" first - it should "GO", but may have some resistance.
Try the .007" - it should not go -- i.e. "NO GO"
If so, the clearance is Good.


IF .006" is a "NO GO" - then try .004".  
If .004" is a "GO" then decrease the valve shim by one "size".  "Standard" valve shim sizes are in 5's -- such as 250, 255, 260, 265, 270, 275, etc.  
But, if .004" is also a "NO GO" (or is very difficult to slide in) -- then decrease 2 shim sizes.  For example, it is a 270 -- then go down 2 sizes to 260.  

After you change your shims DO NOT remeasure your clearance (I got schooled on this recently!).  You MUST get the engine up to operating temp AND LET IT COOL OVERNIGHT to be able to check your work.  If you try to remeasure your clearance after swapping a shim without running up to temp you WILL bet a BAD measurement and will then swap to a WRONG shim.  

For the EXHAUST side you are looking for a "GO" at .008" and a "NO GO" at .009.  

The golden rule on valve clearances is too much is a LOT BETTER than too little!

My shim tool is on it way,so I can't remove my shims yet.if on intake side .00 6 is loose as a goose is that ok?

[Shane4371]

Ok guys I just got home from work bee line to the feeler gauge and checked intakes .004-.006 on intakes all are good,I very pleased,on exhaust .004-.006 I was amazed their all very good the key is have the can lobes in a certain spot and replicate that with all lobes.thanks so much.now to my head bolts and can caps.

[copper]

.004-.006 is too tight on the exhaust side. Yamaha's spec is 0.0062-0.0079 in. on the exhaust side. The .006 is within spec but still on the tight side of the specs and are only going to get tighter. I run intakes at .005-.006 and exhaust at .007-.008.

[Shane4371]

Ok I'll double check.give a min.

[Shane4371]

.008 is very very snug and .006 is loose,am.I good?

[racerrad8]

The smaller the measured clearance the tighter the valves are. If your exhaust are .006-.008 they are within spec. If they are .004-.006 like you stated they are too tight and on the tight side of the spec.

Robert - RPM

[Shane4371]

Thank you randy.I rechecked and Im snug on 008 and easy slid in on 006.

[Shane4371]

Pulled this shim was catching my gauge on the way in.I don't think this is normal and Thiers no numbers indicating size

[FJ_Hooligan]

How does the cam lobe look?

I swear that looks like it used to be a quarter.  When swapping shims around, a quarter can be used as a temporary place holder.

Looking at the side, does it look like it's a metal sandwich?

[Shane4371]

Im a diesel mechanic by trade it makes my living.I could tell this bike wasn't right.I'm in it now to deep to turn back.I need you alls help.should I remove this head and start over?