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[SILVER ROAD KING]

I have Installed a set of Kuryakyn 625 Gear Drive Cams in my Bike and I Have something making a Knocking noise now. I have a 95 with a set of the Harley HTCC Screamin Eagle CNC Ported Heads Jims Rocker Arms Screamin Eagle Adjustable Pushrods and Lifters. I removed a set of S&S 585G Cams That made no noise at all. The Bike was set up with about 30 Thousands clearance for the Piston and Valves before the change my question is it possible for the difference in the Cam Lift and Duration causing the Valves to make contact with the top of the Pistons? The Bike runs smooth no vibration does not miss cranks good just has this knocking noise. I am by no means a Engine Builder But I have Changed the Cams two other times with no trouble at all. The info in the Screamin Eagle Catalog says that the Heads will handle up to a 650 Lift Cam ! What am I missing with this Cam ? The Guy that built my Engine is going to look at it for me in about a Week but I am curious to know if anybody has any ideas 

[sadunbar]

I have Installed a set of Kuryakyn 625 Gear Drive Cams in my Bike and I Have something making a Knocking noise now. I have a 95 with a set of the Harley HTCC Screamin Eagle CNC Ported Heads Jims Rocker Arms Screamin Eagle Adjustable Pushrods and Lifters. I removed a set of S&S 585G Cams That made no noise at all. The Bike was set up with about 30 Thousands clearance for the Piston and Valves before the change my question is it possible for the difference in the Cam Lift and Duration causing the Valves to make contact with the top of the Pistons? The Bike runs smooth no vibration does not miss cranks good just has this knocking noise. I am by no means a Engine Builder But I have Changed the Cams two other times with no trouble at all. The info in the Screamin Eagle Catalog says that the Heads will handle up to a 650 Lift Cam ! What am I missing with this Cam ? The Guy that built my Engine is going to look at it for me in about a Week but I am curious to know if anybody has any ideas 

Are you confident there is no interference between your rocker arms and rocker boxes?  Perhaps you have a lifter that has not pumped up?  Perhaps there is a pushrod out of adjustment?  Check the easy things first....

[SILVER ROAD KING]

Are you confident there is no interference between your rocker arms and rocker boxes?  Perhaps you have a lifter that has not pumped up?  Perhaps there is a pushrod out of adjustment?  Check the easy things first....

Checked the Boxes with putty to be sure been thru the pushrod adjustment 4 times and have let the Bike run long enough to pump up Lifters (called my engine guy he told me to let it run may be lifter) noise does not change

[HD Street Performance]

Maybe the retainers are hitting in the boxes, did you check there? The base circle is not that different from cam A to cam B to have the rockers hitting if they are stock. If you have rollers I suspect they are hitting and I automatically relieve both the pushrod and the rocker end parts of the box when rollers are used.

Regarding piston to valve
You raised the Intake .054" more and the exhaust .003 at TDC (not the closest point, the valves are actually closer at 5 or so degrees before and after TDC on overlap part of the cycle). Would depend on how close you were before the swap if there is interference.

[SILVER ROAD KING]

Maybe the retainers are hitting in the boxes, did you check there? The base circle is not that different from cam A to cam B to have the rockers hitting if they are stock. If you have rollers I suspect they are hitting and I automatically relieve both the pushrod and the rocker end parts of the box when rollers are used.

Regarding piston to valve
You raised the Intake .054" more and the exhaust .003 at TDC (not the closest point, the valves are actually closer at 5 or so degrees before and after TDC on overlap part of the cycle). Would depend on how close you were before the swap if there is interference.

I have Jims Rockers in stock rocker boxes. Took my Bike back to the Guy this evening that built it for me he is thinking  kinda the same thing you just said after listening to the noise it is making he told me that he done some relieving in the boxes when he built the engine but I had Harley 251's in it then and I installed the S&S 585's and ran it for a good while with no problems then I got a wild hair after riding a bike with the Kuryakyn 625's to try a set in mine and now I have this whacking noise. Will I have to change the valve springs in my Harley CNC Ported heads to run this cam ? they say they are ok up to a 650 lift cam. Another question I have is about Head gasket thickness I am having trouble getting gas that will not make the valves rattle even before the 625 cam swap We checked the compression and it is 200lbs what is your thought on using thicker gaskets to lower the compression since  we may end up pulling the heads if the problem is not in the rocker boxes