help wanted with nc30 valve clearances

[speedy231278]

Shim and the rocker arm.

I feel a realisation of stupidity coming on here

You do realise that the photo in the Haynes manual of where to check the clearances actually incorrectly shows the feeler gauge between the rocker and the cam, don't you? If I'd not visited this forum, when I come to do mine, I'd be measuring the wrong thing and probably end up with a knackered valvetrain. There's a difference between stupidity and someone with a lack of experience being given duff info...

[bikemonkey]

I didn't take much notice of the pictures in the haynes when I did mine, I used the guide on here more so I wouldn't have seen that

[speedy231278]

What's slightly worrying is that it makes you wonder what else is out there that they've cocked up that people haven't spotted!

[NGneer]

Stefan - tried and tested guide by one of the guys here...

viewtopic.php?f=24&t=1943

[VFRkieran]

I had allmost all of mine close right up like yours, i dont think they had been checked for a very long time as some where right down to 0.04mm clearance like yours.

However i now have the heads off and there is no indication of anything being damaged, i had one valve guide that had dropped down and a big build up of carbon (expected) there have been no other problems.

As long as there is some clearance then you shouldnt have damaged anything, the race manual states that clearances be set up tighter anyway because it actually runs better however 0.04mm is bloody close to piston/valve contact and a written off motor!

[stefan]

do you no where i can get the right feeler gauge

[bikemonkey]

You can get one from any good toolshop/autostore.

Just make sure you get one that ranges at least from 0.05mm to 0.4mm.

Got mine from halfrauds and it works just fine

[stefan]

thanks for all the replies i checked the clearances again today and some are within tolerances, i still have some of the inlets that are only .10mm but its not as bad as i first thought. anyone know the best way to work out the correct size shims i will need for the ones that are a bit tight

[bikemonkey]

Take the shim out and use a micrometer or vernier calipers to measure it.

Be very careful when taking them out and putting them back in, fill any gaps/holes around the area with rags/kitchen roll so if you do drop them they won't go into your engine.

Use a magnet on a stick to get them out. And again, be very careful. You don't want to have to strip your engine to find a tiny shim.

If your gap is say .10mm and your shim is 2.35mm then to get back to spec you'll need a smaller shim. But not too small to make the gap too loose

EDIT: And obviously if your gap is too big you need a bigger shim.

[stefan]

thanks do you know where i can buy the shims from