So I am at 18k miles and have not doe the valves or the major things at 16k. I am going down as far as the valves, and possibly carb synching. When got to the camshaft cover I noticed that there were several cracks over piston 1. I have recorded the specs: What is causing these cracks? Should I be changing this cover?

INTAKE:
1. .178/.152
2. .178/(.127/.152)
3. .178/.152
4. .178/.178

EXHAUST
1. between .229/.229 & .178/.178
2. (.178/.203)/.178
3. between .229/.229 & .178/.178
4. between .178/.178 & .203/.203



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It's hard to tell from the pic if they are cracks or just casting marks. Do you mean the lines around the 14 and 4 numbers? If they are genuinely cracked then it needs replacing.

The interesting part of replacing them is that the cam cover (the bit with the cracks) and the cylinder head wear together and should be replaced together, you can sometimes get away with just replacing the cam cover but it is not good practice and can end badly. If you look at a parts fiche you will see that the head and the cam cover are sold as one piece for this very reason.


In other words, seriously hope that the cover is NOT cracked.

 

I guess I will need to see if They show cracks on the other side. I really hope this is nothing, as I remember my 400ex also had these, but on the outside, and so far its still been running strong.

Also do my specs seem real off? or is this normal for out of spec valves? I feel like they are a big jump from original spec.

Here is the 400ex. I remember others have said this was nothing major, like you said, the casting marks.



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All of your valve clearances (i.e. ALL 16!!!) are tight after 18k which is unusual, most CBR owners get to 32k without needing to adjust anything. My guess is you either abuse the bike regularly or you are measuring them wrong...


Either way once you are happy with the measurement dig in and measure the shims in each valve (labelled bags/boxes are a must), you can normally get away with swapping them around and just buying 1 or 2. 16 tight valves seems a bit much though.



The marks on your second set of pics are just casting marks, I'd hazard that the marks on your CBR are also casting marks but it is hard to tell from photos alone, biggest clue is that cracks don't usually have nice smooth and rounded outlines like the marks on your CBR.

 

I have to admit, even I, who am the most concerned about abuse in all things that need replacing/maintenance, have been beating on this bike pretty good, for at least the last 2 seasons. The second season is getting much more abuse comparatively.

I ride this more like a toy than a commuter. Also the PO did not take care of the bike either. The chain was badly rusted, probably from sitting outside.

I am super sure I measured them at the correct TDC by rotating the crank until the T lines up. Then turning it 180 degrees and line up the I, for the next measurements, and so on, according to the FSM and http://www.bayarearidersforum.com/fo...t=85499&page=5

I was a little worried as well as to why they all measured so much tighter, so I tried every combination possible by mix and matching feeler gauges to get different readings, but soon to find out those mix and match specs where already part of the feeler gauge cluster. I proceeded to try every possible one and those numbers showed up.

 

If you are happy with how you checked them then I'd be inclined to believe the results, there aren't many ways to misuse a feeler gauge. The engines can handle the abuse though, so long as you stay on top of your maintenance and check the clearances regularly you shouldn't have a problem with ringing it's neck every now and then.


Measure all of the shims one at a time and see if you can swap them around, shims are surprisingly expensive individually. If you do need loads of them then buy a shim kit, would probably be cheaper.

 

So I forgot to mention that I was riding alot when the cam chain started rattling. To the point were you could hear it, and then also hear it get even worse. Could this have been the culprit?

The majority of the shims I need are
(7)1.90
(2)1.95
(1)1.40
(4)1.85
(2)1.80

Outrageous..