Head Case

[Geeen]

This may be the wrong forum for this, Please feel free to move it Mods.

Anyhoo, I came across this on you toob today and thought "Damn thats cool"


http://www.youtube.com/watch?v=c8hqoE1_7bA&feature=g-hist

Can anyone tell me which side is inlet and which is exhaust?

[Laava]

RH is the inlet. Why did you want to know?

[unstuck]

That was cool.:niceone: Amazing how much those valve springs turn.

[Geeen]

RH is the inlet. Why did you want to know?

Curiosity.Was looking at the different winds of the springs and thought "I wonder...."

[slider39]

Yes interesting engine design, and I don't know how common it is, where the crank turns clockwise but cams turn anti-clockwise when viewed from cam chain end.

[Ocean1]

That was cool.:niceone: Amazing how much those valve springs turn.

They tend to turn anyway but having the valves turn is a good idea, (even wear, evens out hotspots in the exh valve seat), so much so that many spring retainers have a wee mechanism that makes sure they do.

Interesting to see the springs oscillate through several harmonic phases as revs go up.

[pritch]

And the Ducati owners look at that and wonder why?

[steve_t]

And the Ducati owners look at that and wonder why?

Why what?

http://www.ultimatemotorcycling.com/2012/bmw-recalls-2012-s1000rr-sportbikes 2012 BMW S 1000 RR Motorcycle Recall :msn-wink:

[pritch]

Why what?


Why would you limit yourself by using valve springs? :whistle:

[Laava]

They tend to turn anyway but having the valves turn is a good idea, (even wear, evens out hotspots in the exh valve seat), so much so that many spring retainers have a wee mechanism that makes sure they do.

Interesting to see the springs oscillate through several harmonic phases as revs go up.

Funny thing is, they will be doing that naturally but the camera will be doing it also because of frame rate, so it may not be in real time IYKWIM.
Is that your LOKI on TM? How do you like it? I am leaning in that direction ATM.

[Ocean1]

Is that your LOKI on TM? How do you like it? I am leaning in that direction ATM.

No, mine's a white CR, one of the last ones to escape.

It's sorta a natural progression from previous bikes for me. There's other machinery around with similar charecteristics but none with quite the same mix, it's very short, very light and matches most of the rest for HP. Suspension is good, wide range of adjustment fwiw, but not as good as the setup on, say an 1198. You'd be seriously pushing it to figure that out, though, and the cost is less than half any top shelf Duc. Not so obvious is the torque spread, it's everywhere, (think it's the same at 3500rpm as it is at 9000) and it's huge, so unless you're on the track changing gear is largely optional. On the road just roll it on and it climbs out of corners quicker than anything I've ever ridden.

[Bass]

Interesting to see the springs oscillate through several harmonic phases as revs go up.

Are you sure that wasn't just the stroboscopic effect of the camera's 24? frames per second?

[Ocean1]

Are you sure that wasn't just the stroboscopic effect of the camera's 24? frames per second?

No, not sure. I know it's got to happen, though, there's no damping involved and any spring will have a natuaral frequency, multiples of which will certainly be represented in such a rev range.

[Bass]

No, not sure. I know it's got to happen, though, there's no damping involved and any spring will have a natuaral frequency, multiples of which will certainly be represented in such a rev range.

Thats true, however my guess would be that the natural frequency of the bare spring would be well above the rev range of the motor. Not sure but I think it might be the frequency generated if you give it a tap like a tuning fork.

The natural frequency of the entire reciprocating mass might be within the rev range but.