Tips for 5th Gen Valve Clearance Inspection

1999, 18k miles, unknown service history. Five tight valves, two are loose.

 

What I usually do if I have to pull the cams anyway, re-shim or swap shims to get clearances slightly above nominal, i.e, 60-70% of max. Clearances always get smaller not bigger. Then you can extend check interval.
I buy individual shims at RockyMountainATV, as they are available in 0.025 increments vs. a HotCams kit. Buy a couple extra just in case.

Edit added - I just realized Honda's range is +/- .001" (others are slightly higher), so I will revise my preference to lean towards or at max tolerance, intakes in particular. Exhausts have a larger nominal than most, so IMHO they're OK if nominal to max.

 

so do you adjust intake looser and exhaust tighter?

 

No both looser rather than tighter. I realized in my post I forgot to add the words 'of max', so I edited it, and added another comment at the bottom.

 

wouldn't you set the exhaust tighter, using that logic? so if they loosen , they will be in spec longer?

 

They never get looser, only tighter.

 

so the loose exhaust valve clearances I have were set that way by Honda when bike was built?

 

What clearances did you find? Did you rotate the engine and check more than once? Was the feeler free to move in/out/around or snug?

 

two exhaust valves are at .013

 

Spec. is .012 +/- .001, so perfect.

 

since I'm in here I added .001 to shims, now its perfect

 

How did people manage to get the front valve cover out of the way to do the shim adjustment?

I just checked my clearances but couldn't see how I would get the cover completely out from behind the rear wheel without draining the cooling system and removing one of the radiators?

The rear cover came out by removing the trumpets in the airbox and just raising the back end a bit.

The 86's were much easier to access.

I agree with the comments in the thread that say a "bent" set of feelers is useful for this job. I'll be ordering a set before the next check.
It took a bit of practice to get the "feel" for the feelers. I only have a straight set of feelers and the bend required to line up with the accessible path to the camshaft for most valve locations adds drag to the feel. I used the outside intake and exhaust valves on the #1 cylinder to get a straight path from the center of the head to measure the clearance to determine the measurement. I then went to the outside of the head to measure the same valve. This is the path required for most of the locations. Much higher drag on the feelers given you have to bend them around a curve to line up with the top of the follower.

Luckily all valves were within the specification although many were at the tighter end. Next time I go in I'll be planning on replacing shims so it will be an end of season job so I'm not rushing. For that I'll have to get the cover completely out of the way.

Thanks,

 

I won't be attempting a check or an adjustment,
so does anyone have a suggestion for a good mechanic
for such in the San Diego/SoCal area? Thanks...