Rocker Arm End Clearance

[Dave_Faria]

GM List. I've got a 2004 R1150RT(34k miles on the engine) with a little cam chain slap at idle on the right side and wanted to know if closing the rocker arms end clearance would make any difference. I looked at the oil distribution circuit shown in the BMW manual and the rocker arms are the last item to see lubrication. My idea is closing the clearance would divert more oil and pressure to the cam chain tensioner(right side). I know the Cam Chain tensioner(right side) has an orifice which restricts the amount of oil flow. I have the new style cam chain tensioner on the left.

What I'm curious abt is if the rocker arm oil circuit also has an ORIFICE that restricts oil flow. If it does have an oil regulating orifice then closing the end clearances will do nothing more than reduce mechanical noise at the rocker arms.

At present my rocker arm end clearances(set up by me and not by the dealer) are .0025in./.003in. on the intakes and .004in. on the exhausts.

So my final question is will I gain any more oil pressure at the right cam chain tensioner if I close all the rocker arm clerarances to .002in. Is the effort worth the trouble???

Thanks List for your comments.

[PGlaves]

GM List. I've got a 2004 R1150RT(34k miles on the engine) with a little cam chain slap at idle on the right side and wanted to know if closing the rocker arms end clearance would make any difference. I looked at the oil distribution circuit shown in the BMW manual and the rocker arms are the last item to see lubrication. My idea is closing the clearance would divert more oil and pressure to the cam chain tensioner(right side). I know the Cam Chain tensioner(right side) has an orifice which restricts the amount of oil flow. I have the new style cam chain tensioner on the left.

What I'm curious abt is if the rocker arm oil circuit also has an ORIFICE that restricts oil flow. If it does have an oil regulating orifice then closing the end clearances will do nothing more than reduce mechanical noise at the rocker arms.

At present my rocker arm end clearances(set up by me and not by the dealer) are .0025in./.003in. on the intakes and .004in. on the exhausts.

So my final question is will I gain any more oil pressure at the right cam chain tensioner if I close all the rocker arm clerarances to .002in. Is the effort worth the trouble???

Thanks List for your comments.

I don't think it will make a difference you can detect. I have adjusted mine right to the minimum spec and within the spec range I can't notice a difference in valve train noise - let alone a difference upstream at the tensioner.

Mine is just plain viscosity sensitive - new oil = no tensioner noise to speak of. 3K to 4K on the oil - the noise reappears.

[Dave_Faria]

Paul what is the viscosity is of the oil you are running and what brand. I've tried 2 different types. Mobil 1 15w50(viscosity 17.1@200F) and Mobil 1 20w50 Vtwin(viscosity 20.1@200F). The Vtwin oil has been in the engine a little under 100miles and seems at this point to help the chain slap. But, the oil has not aged yet and the chain slap may return. I know this is probably a question not needing to be asked but, what is the chance the chain rails have not worn in??? This my 1st oilhead and it still uses oil at 34k miles. Last I checked it used 1 qrt in 1200 miles using mobil 1 15w50. The oil usage was worse using dino oil.

Thanks for ur comments