A Journey Into the Red

[Eklipse]

So I'm on my way home from the Thursday night Marine Pool Function (my first one, I'm so sore...) cruisin along at highway speed (mostly), 80ish on the speedo for whatever that counts and I decide to play with the gears and see which gear gives me what kind of power/rpms.

Sixth, Fifth, Fourth... pretty nice... one more: Third. Whoa 10.5k RPMs. Hmm, let's pass this car: 11k... in the red and not stopping? Interesting, I thought it would stop there. 11.5k... Gotta slow down soon...

12,000 RPMs (ish). Waaaaaaaaaaaaaaaaaaa .... (silence) .... no throttle response. Uhm... bike died. Won't start! In traffic, slowing down! Must pull over three lanes of traffic before I get ran over!!

So I pull all the way to the right trying not to die by the now-moving-faster-than-me-vehicles while panicking because my bike just died as I hit 12k RPMs all up in the red and it smells, uhm, like it probably shouldn't smell!

On the side of the interstate at night, bike won't start. Ok, switch to reserve. Still won't start!

I'm gonna DIE if I broke my bike oh my gosh. FINALLY! IT STARTS!! YES!!!

So I didn't blow anything up, I was just out of gas. WHEW! Apparently I had been enjoying that tank of gas because I only got 165 miles out of it  :lol:

Anyway it was a very scary experience, your bike dying in traffic as you redline it and having to coast through three lanes of speeding traffic and HOPING you just ran out of gas.

On a side-note, I found out tonight how easily the GS will wheelie with a passenger on it when you're not even trying.  :dunno: But hey while I was like uhmmmm whoa I didn't mean to do that, my passenger was like HOLY CRAP GO FASTER! So I covered myself pretty well  

Now he's thinking about getting a bike, and a STARTER bike at that, such as the GS or other 500, or 250. Who says everyone has to be a squid?

Sorry if you didn't understand any of that, but three hours of exercise-stuff-you've-never-even-dreamed-of-doing-when-you-haven't-worked-out-in-three-years will do that to you.

[Ed_in_Az]

Sounds like you lucked out there. I haven't done any trips into the red zone. Week before last I did have one of those occasions to try gearing down and speeding up though. :mrgreen:

On one of my local rides is a set of uphill sweepers. Right, left, right again. Double lane, and it gains about 1,500ft in 2 miles. I started up at 80mph in 6th. I dropped to 5th and acceleration wasn't impressive so I dropped to 4th.   The little GS came alive.   I was doing over 90 and over 10,000rpms, real guick. I kicked it back up to 5th, slowed to 85mph and held it there the rest of the way. I don't know how fast an I4 would take those turns, but in a 65mph zone and no wind protection that was fast enough. Plus the speeding ticket would not be good.

[Blueknyt]

valve float starts around 12500, ive gone 11k no problem, the gs really stops pulling around 10,5 to 11, after that its just spining.  if you run up to about 10k,then shift, you wont see any difference then if you shift at 11k. there isnt any real power upthere.

[JamesG]

You got lucky punk.

Here is what can happen with sustained engine abuse and valve float:

[The Buddha]

Hey it just wanted a shim swapped...
Anyway... ~7-8K mine makes some seriously shitty noises. It seems to continue till the ~9K I have revved it to. Would it float valves at 7-8K. Well what it it had 45K miles....
Cool.
Srinath.

[MarkusN]

Anyway... ~7-8K mine makes some seriously shitty noises. It seems to continue till the ~9K I have revved it to. Would it float valves at 7-8K.

You might have a tired valve spring or two. Which could bring the critical RPM way down.

[scratch]

Don't these have a rev limiter? An electronic cutout that cuts the spark to the sparkplugs when you reach a certain rpm (usually in the red zone).

[Eklipse]

I don't know if they have a rev limiter, but I know my car does  

That is one seriously messed up engine. What's valve float?

[MarkusN]

That is one seriously messed up engine. What's valve float?

The valves are opened by the cams and close under spring load. Acceleration of the valves by the springs is limited by valve weight and spring ratio. If RPM demands more acceleration from the valves than the springs can deliver, the closing times of the valves start to lag behind. That means that the tappet does not stay in contact with the cam; the valve floats. The first result of this are too long opening times with the correponding results on the gas exchange. If the condition gets severe, Valves can collide with pistons. You can imagine the results (and observe them on the image above).

This is an inherent problem of all engine designs working with valve springs. One way around this is valve control that forces both the opening and the closing movement with cams. This is called desmodromic valve operation; it's a hallmark of the "desmo" Ducs.

[PAC]

This is an inherent problem of all engine designs working with valve springs. One way around this is valve control that forces both the opening and the closing movement with cams. This is called desmodromic valve operation; it's a hallmark of the "desmo" Ducs.

You sir, get a gold star for the day.  I have always wondered what "desmodromic" valves meant on Ducati's, but was always too lazy or never remembered to go look it up.  Now I know.  Thanks!!