Did Ducati ever fix the rocker problem?

Re: Did Ducati ever fix the rocker problem? (PSk)

First, yes the problem is not gone. Picture is of a 2002 748R with 4000 miles.



<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PSk »</TD></TR><TR><TD CLASS="quote">
I suggest you look at the Nichols rockers at 6k too ... as all wearing surfaces will end up with this sort of pattern ... EVEN car rockers that are not desmo but simple pushrod rubbish.

Something does not rub against something else and not end up with any wear marks at all ... just does not happen!
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Pete</TD></TR></TABLE>

Maybe I'm stupid, but I thought there were an oil film to Prevent metal to metal contact...

/Uffe

Re: Did Ducati ever fix the rocker problem? (uffe_e)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by uffe_e »</TD></TR><TR><TD CLASS="quote">Maybe I'm stupid, but I thought there were an oil film to Prevent metal to metal contact...

/Uffe</TD></TR></TABLE>
Yes but you still get a polish mark on any rocker. Car engines have oil too ( ) and guess what they rockers wear out or develop a wear pattern as well ... thus ofcourse Ducati rockers are going to develop a wear pattern. Ducati engines are no different to any other engines ... other than the desmo stuff (but other manufacturers occasionally play with that too).

The point I am trying to make is that it is 100% normal for a part that rubs against another part (even with oil) to develop a wear pattern and over time wear. Now how long it takes to wear depends on the hardness factor, lubrication (on start up especially), etc.

It is NOT normal though for a hardened surface to prematurely flake. But flaking and normal wear patterns are NOT the same thing.


I suggest you put some oil on your hand(s) and rub it against something else a couple of million times and see how much skin is lost

. Oil is lubrication not a physics and/or force isolator.

Thus cam pushes on rocker which pushes on valve ... now are you telling me that at high rpm when the F = m.a calculation starts producing high forces that our little oil film is always going to survive ... even oil must get squished out when the forces get too high. Now in the case of a crankshaft we have a pressurised oil feed thus as the oil gets squished out, in comes some more and all is beaut. But these rocker faces do NOT have a pressurised oil system between cam and rocker face ... they 100% rely on the oil film or cloud in the cam box area. Thus again at high load points we cannot always guarantee that oil will always be there.

Does a Ducati cam have a cam lobe oil feed hole? ... some engines do, and thus oil is applied to the rocker ONCE every cam revolution. That is all, and if Ducati's don't then again it is just the oil cloud in the cam box that lubricates these rocker faces.

Pete


Modified by PSk at 10:04 PM 4/28/2005

Re: (superbike2001)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rmani »</TD></TR><TR><TD CLASS="quote">
can someone explain to me exactly what the rocker problem is? I've read about it before but I don't understand how this affects the engine.
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If you do a search here you'll find plenty.

In short, the rockers arms which transfer the motion from the cams to the valves has, most believe, an inadequate chrome layer which sometimes flakes off. Th e chromed surface are the one in contact with the cam lobe surface. When flaking occur, the material of rocker surface is quickly worn down.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rmani »</TD></TR><TR><TD CLASS="quote">
If I bought a bike and it suddenly had this problem how would I know about it and would it result in a costly repair?
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Often, but not always, depending on how far it's gone, you can find small chrome flakes in the oil filter mesh. Normally you will only have to replace the damaged rocker(s), sometimes the cam can become worn and ultimatly a valve may snap caused by excessive valve play. That can be really expensive.

I don't think you can ever hear excessive valve play in these desmo engines, they are so damn quiet or the clutch is so damn loud...

Re: (Old Baldy)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Old Baldy »</TD></TR><TR><TD CLASS="quote">All very true, but I've yet to find a regular production car engine that wears it's rockers through the hardening and frequently starts camshaft damage, at less than 10000 miles.

That wear would NOT be considered normal, IMO.</TD></TR></TABLE>
Agree.

The point though that I was trying to make is that I think some people are confusing normal wear marks with flaking rockers. Yes Ducati can't (for some stupid reason) harden the rockers properly but I've seen pictures on this site of what looks like normal surface/wear polish marks and the photo taker getting all excited about flaking rockers. Any rocker will get a wear mark, the difference is Ducati's [email protected] ones surface cracks and thus flake and then sh!t the cams

I do have to say (again) I cannot justify the desmo complexity for a road engine. Now for racing ... if it makes extra power or torque and could make the difference in the race result, well heck anything goes


I also agree with Buckelew's comments ... which highlights the fact (to me anyway) that there is a major flaw in Ducati's heat treatment or something. Amazing ... It is a joke, ie: How many years does it take Ducati to change a light bulb? Why bother people are still buying them

Pete