I have a 04 CBR600RR with around 20k miles. I had a shop recently check my valve clearance and do the CCT install with another OEM Honda one ( perhaps a mistake?) I'm thinking I should have went with a APE one for them to install. Anyways, with the OEM Honda one I noticed from a cold start I can hear a rattle on startup for like 3-5 seconds then it goes away as it warms up. ( I should really start doing my own work)

I called the shop and they explained to me " That's normal from a cold startup, hydraulic pressure needs to build up from the oil. It goes away right? Yeah, most CBR's do that. If it gets louder bring it back in"... I'm wondering how much of that is true vs BS? I've read 954's having the same issue, even when they replace them with another OEM one. Majority owners report manual APE's completely get rid of it 100%

 

I thought the stock 600RR used a spring tensioner, rather than oil pressure? (my '91 uses oil pressure and occasionally makes noise for 1 or 2 seconds after start up).