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Discussion Starter #1
I checked my valves about 5k miles ago. They were all approximately at minimum tolerances. I am now at about 41k miles and checked the valves again last night. All the intake valves were at 0.18mm (spec is 0.17mm to 0.23mm) and the exhaust valves were at 0.22mm (spec is 0.25mm to 0.31mm). I also noticed that the line at the "T" mark at TDC did not line up with the cam markings for the top of the head and had to be rotated about an 1/8" to line up the cam marks. Is my cam chain stretched or is this normal? Is there anything else I should check while I am in there like compression or leakdown test? Should all the valves be adjusted to the middle of the specs?
 

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For what it's worth I've had the marks not line up exactly on bikes with only a couple thousand miles on them.

Seems to be some leeway there. I don't know what the recommended replacement interval for cam chains on these bike is but on the 80s UJMs the rule of thumb was 40k, though catastrophic consequences are unlikely even if you never do it. Especially if you're not hearing noticeable rattling when the engine's running.

Since valves tend to tighten I'd err on the high side of the spec range, especially on the exhaust side.

I'd do a compression test since it's easy once all the stuff that's in the way has been removed. Pretty much the best indicator of your overall engine health.
 

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Thanks Bat-1. I am hesitant about taking the cams out, but it looks like it needs to be done. Gonna recheck them tonight as I watched some videos on using feeler gauges to get an idea of how much drag to look for. I have most of the connections on the bike unplugged. Do you know if this will cause any issue with cranking it over for the compression test? I think I remember the fuel pump relay needs to be removed.
 

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For the compression test you'll have the valve cover back on, battery hooked up, all the spark plugs removed. You put the tester in each of the cylinders successively while cranking the motor with the starter (fuel pump unplugged or fuse removed since you don't want any gas in the cylinders). As long as the motor is turning over your test will be fine (lights, temp, exup etc. play no role).

The consumer level testers don't give terribly accurate readings so don't fret if you're not getting the spec 178ish psi. As long as all your cylinders are reading close to the same you're probably fine (it's beyond unlikely that they would all be the same amount low or high).
 
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