cam lobe to head casting clearence

[gunt]

Hi guys

its probably already noted somewhere but i can't find it , when installing a new cam with more lift , [ this is a bike engine zx10 2004 got roped into building it ] and heading for 13500rpm
question is whats the rule of thumb or definitive fact on clearance from the cam lobe to head casting as it starts lifting / closing tappet , i had a measurement of 1.3mm and now i'm down to .7m this is also playing with a cam still in the family range not after market and in its own 08 head it has the 1.3mm clearance , intake cam , i would have definitely not question taking out material if this was on the exhaust cam

Cheers in advance

[CamKing]

Clearance is clearance.
If the cam lobe is moving more then .2mm, you've got other problems to worry about,

[gunt]

As it rotates to open the valve and comes close to the casting that supports the bucket

[CamKing]

As it rotates to open the valve and comes close to the casting that supports the bucket

As long as it clears the casting, you have no problem. It's not going to get any closer to the casting when it's running.

[gunt]

Hi

Thanks , the larger clearance in the head that the cam came out off made me question it

Cheers