VN V6, Sticky lifter or valve?

[Mitch_calaisVN]

Hi there
Since I've had my VN it has idled rough, and only on number 4 cylinder, so I replaced spark plugs and leads, injector, coil pack and it still idles rough so I thought it might have been a blown head gasket but the car always sits on a quarter on the temp gauge even going up steep hills and it doesn't leak coolant, so I'm thinking that it is a sticky lifter or valve? Has anyone had this same problem? If so how do I fix it, the car is fine when driving it is just at idle, Should I just leave it?, any help would be great!
Thanks

[tntracing]

do a compression test on all cylinders and write down the results,compare the readings a few psi difference is ok but if you have a stuck valve it will stand out.
Also does your radiator coolant bubble when the car is warm and the cap off?

[Shortstuff]

Yeah, compression test is quick and easy to do. I spoke to a mechanic who has worked on VN's from new and he said they used to have problems with the camshafts wearing. You could also take the rocker cover off and run the car for a short time to see if the rockers are going up and down. I did this when I had problems with mine and it's not too messy!