strange knocking noise poss piston slap vts

[rob69vts]

hi all

heres some videos of my vts when started from being left over-night
http://i23.photobucket.com/albums/b364/roblemon69/th_video-2011-07-31-12-15-12.jpg (http://s23.photobucket.com/albums/b364/roblemon69/?action=view&current=video-2011-07-31-12-15-12.mp4)

that almost goes away after a minute or two.and sounds much better (only .8 mile down the road)
http://i23.photobucket.com/albums/b364/roblemon69/th_video-2011-07-31-12-24-44.jpg (http://s23.photobucket.com/albums/b364/roblemon69/?action=view&current=video-2011-07-31-12-24-44.mp4)

i changed the cambelt and water pump and all tensioners last month because the sound is louder from that end of the engine.
if i use a stethoscope on the exhaust cam pulley area of the cambelt cover the sound is much louder that any where else on the engine (can here its louder in the first video around 28 seconds).

really hoping its just lifters or something simple as it just started last month.

i'm using 5-40 fully synthetic oil that was changed with filter less than 1500 miles ago

[RustySkull]

5-40 huuhhh, I use 15-W40.

Try thicker oil :)

[rob69vts]

Any more suggestions people.

[rob69vts]

changed the oil to semi synthetic castrol magnitec 15w40 still no change to how it sounds.

no lose of power so just going to keep on driving
just sounds nasty for about 90 seconds when started then sounds ok .

[JAGVTS]

Was gonna say the lifters aswell . Mine did it after it had been stood for a week. Blip the throttle in the engine bay by the tb. Then gradually build up the revs. Mine did the same thing