yesterday I could not get my 2007 FLHTCU to get over the 120 km/hr and today in idle I noticed excessive vibration. Valve problem?

 

Lets start with a compression test. Do that and list Any Motor work. we'll need to know to point you in the right direction.

 

New symptom. Went for a test ride and after 15 minutes or so, the bike had a hard time reaching 100 kms /hr and the oil pressure gauge was almost at 0. The oil levels were fine before I left.

 

If your oil pressure is almost 0, your lifters are bleeding down and your losing lift and valve timing. That's just the start. You have to find what your oil pressure problem is before you need a motor.

 

Compression is good. 172 and 175

 

Is that a 96" 0r a 103". Compression isn't bad. I have heard of oil sumping in the case which will rob a lot of power out of the motor. There are threads around hear that can help you. Just search "Oil Sumping" it's when the oil builds up in the lower case and is not pumped back to the reservoir.

 

It's a 96 and thanks for the tip on oil sumping

 

Your welcome. I hope thats all it is....Check your oil level that should give you an indication. But do your research.