[Rossman]

rattle

It's not the chains, so throw that out the window. I too have the same noise, but no word from honda yet. My father in law was an engineer by trade, and in discussing it with him he has hypothesized that at a certain RPM there is a point where the valve rockers are potentially vibrating on the cam. Very possible. I guess Honda will have to come out with an official verdict to put us all at ease.

 

[Rossman]

rattle

Hmm, that's very interesting. I still have my head all open (waiting for shims to arrive Tuesday), and have checked everything out top to bottom. Besides there being side-side play on the rocker arms, there is also play on the shaft holding the rocker arms in place and the cap that secures it in the head. There are rub marks on the caps too. Basically, besides these 2 things, everything is solid. There is no scoring, mechanical damage, etc. It might just be a design issue and we'll have to invest in earplugs.

 

[Rossman]

Month made

Feb, 2011.

 

[Rossman]

Dyno

Someone did post a dyno graph on here, and it looks as though our bikes are putting out the most torque at 5500-6000 RPM, so there could be a direct co-relation. Like I said before, I've still got my head open and have squarely inspected anything. My gut still tells me it's noise related to the rockers skating back/forth, or even the dowels that hold the rockers in place seem to be hitting the caps on the side of the motor (bolt caps). That being said, my components look perfect though. No play in roller bearings, no cam scoring, etc. Something that we might not be able to see though, and it could be, is a light form of piston slap.

 

[Rossman]

Update

So here's the latest. My new shims came in for the exhaust, and I put them in. They now measure exactly .011 as required. Take the bike out for a ride, and the rattle seems to have diminished at the 5200-5800 rpm mark, but is still there a bit at 6K. It's definitely made a difference. Also, when my bike is idling now, I can hear the tappet noise from the valves whereas I didn't before when they were tighter.