Help me OB-Wan, You're my only hope!

[Stumpi99]

Hey all,
My first post to the forum so thanks for the content and thanks for reading..

I have a 98 G1 ZX6R as mentioned above and I'm getting a new rattle at around 4000 rpm in the top end..

I have so far replaced
Cam chain
Cam chain tensioner
Cam chain guides
Reshimmed the valves ( 4 times )
Removed PAR reeds and blocked off
Stripped the motor down to check the piston rings and pins,
Rebuilt it up checking all tollerances on things like the valve springs were all good and have torqued it to spec everywhere.
I have removed the thermostat to eliminate that too just incase...

However I still have this noise... I'm wondering if it could be the valve guides perhaps as there is a small amout of play in the exhaust valve guides, although I cannot measure the tollerances accurately.

Would love to hear anyone who's experienced and may have an idea where I should look next or what I could try please. Or who may have a complete motor or head for sale....

https://youtube.com/shorts/smKR3KyFAp0?feature=share

[98ninja]

I had a mechanic friend who said he lost count of the amount of times someone would bring their car in because of a rattling noise thinking it was the engi ne and it was something super simple that was loose and not anything to do with the engine.
Maybe start the bike with the tank off and rev it to 4k and have a closer look in and around the top end area to see if its something non engine related rattling?