426 top end noisier after fitting 450 cam?

[Chris_from_Oz]

In replying to a post in the YZF forum, I recalled my WR426 being (seeming maybe???) noisier in the valvetrain after fitting the YZ450F exhaust cam. It is shimmed spot on, and runs flawlessly, so it didn't concern me too much at the time, and has been perfect since. Anyone else notice this, or did I imagine it, as the bike was not ridden or started in around two months immediately before fitting the 450 cam? I could easily have 'forgotten' what it originally sounded like, I guess??? Anyone? Cheers, Chris

[byggd]

I did this upgrade to my 02 wr426 and didn't notice any noise change

[Chris_from_Oz]

I did this upgrade to my 02 wr426 and didn't notice any noise change

It's OK, i've been thinking back, and i'm almost sure I fitted my bashplate at the same time I fitted the 450 cam.....

*ECHO! ECHO! ECHO!*

[FZ1426]

I noticed it when I went to the Hotcams cam. I think it's because the lobe is about half as thick as the stock cam. A thicker lobe would tend to dampen the noise between the lobe and bucket more. Also the 450 (or Hotcam) is higher lift and less duration which is more of a "hit" on the bucket as opposed to a smoother rolling action. Dig?

Come to think of it, it might even be the decomp mechanism resonating somewhat...

[Chris_from_Oz]

I noticed it when I went to the Hotcams cam. I think it's because the lobe is about half as thick as the stock cam. A thicker lobe would tend to dampen the noise between the lobe and bucket more. Also the 450 (or Hotcam) is higher lift and less duration which is more of a "hit" on the bucket as opposed to a smoother rolling action. Dig?

Come to think of it, it might even be the decomp mechanism resonating somewhat...

OK, maybe it's not engine noise echoing because of the bashplate? Maybe i'm not imagining things? Cheers.

[Hamish]

the cure to engine noise is a louder exhaust system