Rocker Pin Cover wear - Ducati.ms

jobslob · Jan 5th, 2012, 7:08 pm

I've just jumped into my first valve adjustment. From reading LT Snyder's manual, he recommends replacing the rocker pin covers when the pins have worn a gouge into the metal. A couple of my covers have gouges but I'm not sure how far gone they are and if they need to be replaced. Any advice on how much wear is too much?

Also, I've looked around a little bit for covers and it looks like new replacements are a bit pricey. I've found a few used covers but not for the ST4s engine. Is there another source for those covers in case I need to replace any?

thanks for the help, Dan

SS904 · Jan 5th, 2012, 7:54 pm

Mine have a little wear on a few pins as well. Not much, just some rubbing. I don't know what amount of wear dictates replacement. I would imagine it would have to be a decent amount. In any case, all of the 5 bolt rocker pin covers will fit. S4 and S4r Monster, ST4, ST4s, and 2002 748 SBK use the same lowered exhaust cam head and the same covers.

tonered · Jan 6th, 2012, 10:32 am

Same here. Mine have some wear, but I don't see the need to replace them. The oil is definitely getting in there and the rockers are solid.

Have a good one.

Duc2Be · Jan 7th, 2012, 12:01 pm

The problem is caused by the pin not fully seating into the bore. This is because air is trapped between the end of the pin and the bottom of the bore. You can alleviate the problem by putting a light groove into the length of the pin using a dremel tool. Then, use a drift punch to carefully seat the pin fully into the bore before putting the covers on. Good luck!

Corse1 · Jan 20th, 2012, 12:27 pm

Yeah mine are the same and I didn't see the need to replace them as advised by LT. And yes Duc2Be is correct and this small modification is also outlined in LT's manual.

ColinF · Jan 23rd, 2012, 1:05 am

I've watched mine have that same wear pattern for over 5 years without it getting observably worse.I did the dremel air-release groove trick which seems to help but keep in mind an air bubble at the closed end of the shaft seems unlikely to maintain enough pressure to bore a hole through the endplate when all active forces are in a different direction.

RockingM · Jan 23rd, 2012, 6:33 am

I haven't looked at mine since the last valve job but,

could the rocker covers be machined and a bronze bushing installed for a wear plate?

tonered · Jan 23rd, 2012, 9:33 am

I don't think so. The bushing would have no way of staying in place without blocking oil flow to the head. Just my thought.

Have a good one.

RockingM · Jan 23rd, 2012, 2:42 pm

Quote:

Originally Posted by tonered

I don't think so. The bushing would have no way of staying in place without blocking oil flow to the head. Just my thought.

Have a good one.

does the oil flow come through the center of what would be the bushing and the bushing could actually float if so. Next time I'm in there I'll have to check it out. I've never liked running aluminum against steal. Velocettes do it with the cams and I'm trying to come up with a plan in the future to machine out
for a bushing, it's just that the cam caps aren't all that beefy. Anyway probably not necessary as long as one makes sure no air is trapped in behind the Ducati
rocker pins.

yellow blur · Jan 29th, 2012, 10:12 am

rocker pins pushing out..?