Rate my rockers

[TAftonomos]

Doing the 6K service on a 03 ST4s I picked up a couple of weeks ago (months?).  Anyway, I'm un-experienced with the desmoquattro motor, and I'm just not sure if I'm looking at flaking, or just a burnished surface.  Seriously thinking of sending the cams to MBP for polishing, although I do have a lathe in the garage (I'm unsure how to set it up/what to use to polish the cam myself).

I can only feel a small spot on one arm with a pick or my fingernail.  I havn't pulled the closers as they look fine, save for a small grey spot (approx .5x1mm) on the exhaust horizontal.  I can't feel anything on that one either, but I'm not able to get a good picture of it still in the bike.  The grey patch/spot is where the cam would initially make contact, the rest of the place where the lobe would wipe looks/appears to be pristine.

Anyway, let me know what you think about the openers, and that closer if you can.

Pics:

Full shot:



Horizontal Intake Left and Right




Horizontal Exhaust Left and Right - burnishing, but nothing to catch a nail or pick on.  Look like the rockers in the testa motors I've checked.



Vertical Exhaust Left and Right.  -  Note small chip on leading edge on right rocker = bad correct?  I can't get a pick or nail to catch on it either, but sure looks like a chip to me?




Vertical Intake Left and Right - Best looking of the bunch

[DucHead]

Desmoquattro owner here with 37300 mi. on the clock, and I do my own maintenance, so... 

[Speeddog]

A little hard to tell for *sure* from the pics.
But, I'd say they look serviceable.

Polish them up a bit with some scotchbrite and take another set of pics.

You can look at the surfaces nearly edge-on and see in the reflection if the surface is worn down.
Hope that explanation makes sense....

Closer rockers usually don't have the flaking issue nearly as much, the cam is much bigger in diameter so contact isn't as severe.

I'll warn you now, don't remove a closer rocker unless you absolutely have to, refitting it is a *pregnant dog* due to the spring.

[TAftonomos]

A little hard to tell for *sure* from the pics.
But, I'd say they look serviceable.

Polish them up a bit with some scotchbrite and take another set of pics.

You can look at the surfaces nearly edge-on and see in the reflection if the surface is worn down.
Hope that explanation makes sense....

Closer rockers usually don't have the flaking issue nearly as much, the cam is much bigger in diameter so contact isn't as severe.

I'll warn you now, don't remove a closer rocker unless you absolutely have to, refitting it is a *pregnant dog* due to the spring.

Thanks for the opinion.  Can't figure out how to chuck up my cams in the lathe to polish, so I might send'em off to MBP for polishing...in which case I'll send the questionable ones in.  The one that I think has a chip in it....if I run a ballpoint pen across it I can feel the depression....so I'm assuming it's done/will be done soon.

Das why the closers are still in there   I'm going to try and get a pic of the one with the grey spot....but I can't feel anything so I may just let it ride and check again at 12K. 

[Speeddog]

Can't really see the chip you're talking about in that pic.

Tough to photograph, I know.

[TAftonomos]

I changed the image, but it's not very easy to see.  Here is a closeup 

[Speeddog]

Mmm.... yeah, that doesn't look good.

I changed the image, but it's not very easy to see.  Here is a closeup 

[TAftonomos]

I can handle one or 2 out of 16 

Do you replace with OEM, or sent to megacycle or MBP?

[Duckintime]

In my view, from what Ive seen in the past, the rockers look like the beginning stages of problems. Not necessarily now, but you may want to check them again in 6 or so thousand miles. It might be worth it just to have them replaced/reconditioned since you have it all a part. You mentioned about polishing the cam. If the rockers are in good shape, the cam generally shouldnt need to be touched. If you see marks on the cam, the rockers are on their way out.

[Speeddog]

I've sent rockers to Megacycle.
I've replaced with better condition used rockers for one low-budget customer.

Refurbishing a motor now, with new OEM rockers furnished by the customer.

No feedback on the Megacycle rockers, as the guy decked the bike pretty hard shortly after I worked on it.
But, another customer bought it, so eventually I'll get some durability feedback.

I can handle one or 2 out of 16 

Do you replace with OEM, or sent to megacycle or MBP?

[ducpainter]

If you can feel the scratch replace the rocker

I went with used on mine.

[gage]

My 2 cents:

I agree that if you can feel the chip then replace it. I don't neccessarily agree that the others are on their way out. They are going to show some wear and that is not necessarily a problem this is the reason they are chromed; chrome is hard but never the less will "depress" You're looking for places where the chrome is lifting.

Why do you think you need to have the cams polished? are they rough? How many miles?

Related topic:
Has anyone heard any feedback on the DLC coated rockers that I've seen around? I would be really curious to know how well these hold up.

[TAftonomos]

good advice all around.  My testa showed wear marks like these at 6K, then again at 12 and 18, marks just like those posted, never got any "worse".

The polsihing of the cams is another theory because the surface of the cams isn't very smooth....even coming from the factory. 

[gage]

good advice all around.  My testa showed wear marks like these at 6K, then again at 12 and 18, marks just like those posted, never got any "worse".

The polsihing of the cams is another theory because the surface of the cams isn't very smooth....even coming from the factory. 

My cams aren't smooth either. They are not pitted or scored but it is not a "slick" surface

[greenmonster]

On my 907 all but one looked like this (2V):



I carefully sanded/polished them down. Took some time....
set all clearances abit on the loose side. All seat & valve areas refinished.
After 1 season, + 10 000km, all looked well. Will check soon after another 7500km.
1 had a chip lost, you could see through the hardening/chrome. Replaced that,
I think if chipping has started it could be disaster soon.
There you could see that the chrome is quite thick and therefore i think you can save this once.

Just my amateur 2c.