dreaded rocker arm wear

[greenjeans]

1994 XR600R   Took off my valve cover yesterday evening just to take a look.  One of the rockers was worn almost concave...  Cam looks good in comparison.  Now I'll at the very least have to measure the cam and see if it is toast too.   The other rockers aren't as bad.   From the threads I've been reading, oil starvation seems like the most common culprit, however, nothing really looked burnt - just worn the F out.   I have no idea how many miles are on this beast.  It has definitely been apart at least once (you can see tool marks on the bolts.)

Are there any used parts for these?  I can't seem to find much - even on ebay.   I'm only in the bike for $350, so I guess I could put some money into it, but I was really looking for an XR600L when I stumbled upon this one.  Was a bit hard to start but it actually ran pretty good to have rocker wear like that.

So - Are there any used parts stashes that you guys know about?    Or should I just bite the bullet and get new rockers, cam & bearings ?     Then, where do I stop?   I don't really want to buy $1000 worth of new parts for this beast.

[dlock5]

I sure there are other places for parts, but I assume these guys will have what you need.

http://www.xrsonly.com/

[beezer]

I'd look on eBay.  

[S.O.A.N.Z]

You can still get new camshaft and rockers - probably set you back about $400 for the set

How do the bearing surfaces look ?

 

[greenjeans]

Bearing surfaces look shockingly good.   Was surprised at what I was able to get new Honda parts for it. (Rockers & can).  Still debating how far to go.  Piston/rings/valves/seals bearings...   I guess if I keep it, it would be worth it.

[notoriousE-R-I-C]

Where do you live green jeans?
If you're near Huntington Beach, I'll help you with an oem discount.

[greenjeans]

I’m in Texas... digging back into the motor today for a good look

[greenjeans]

Well, it seems to be getting worse.  The 2 outside bearings that house the cam seem good.  They are tight, and spin like new.  One is darker than the other - probably got HOT.  But the center cam journal/surface ain’t pretty.   Is there anything that could be done there?   Or, am I looking for a new head?

I can’t for the life of me find a downloadable pdf of the Honda workshop manual.  I ordered one on eBay last week and received one for an XR400 - still not sure how I did that.

Is there a working link to one that anyone knows of while I wait for my manual to come in?

Also, is there a specific thread to a complete top end rebuild?  Seems like there’s always 1 definitive thread with tips, tricks and photos. 

[greenjeans]

Hmmm...  found a few thread where they mentioned just filing/sanding down that center bearing and going forward.    Not sure about that, although it makes a little sense as the 2 outer bearings would seem to take the brunt of things.  I don't see a hole there for oiling - is there one?  I plan on ordering a new cam, rockers (4) and the 2 outer bearings at the least.  The lower/sub rockers look good(much better than the rest of things), but I'll probably go ahead and grab those too.  

$$$$$$$$$$$$$

[JoeRC51]

The center ''bearing'' is a support for the middle of the hollow cam , it's oiled by the hole in the cam. I'd put the cam in with some plastigage under it and see if you've got a few thousandths clearance. I wouldn't  just go blindly sanding it , it may have more than enough clearance as it is.

[greenjeans]

I’m leaning toward sending it out to XRsOnly for them to weld it up and remachine it.

But - how much clearance could I get away with?

[JoeRC51]

XRs Eventually may not get your head back to you for 6 months , contact Engine Dynamics.

[adnohguy]

R U going to Quit running Rotella now?

[bork]

1 hour ago, adnohguy said:

R U going to Quit running Rotella now?

Curious, why? is there some building evidence of Rot causing problems? I dont run it and probably never will. Just curious.

[greenjeans]

4 hours ago, JoeRC51 said:

XRs Eventually may not get your head back to you for 6 months , contact Engine Dynamics.

Uh oh, It’s already on the way to XRs.  They said a week to a week and a half.  I kinda need it quick.  

[greenjeans]

When it rains it pours.  Turns out the previous owner DID put a new piston in it.  However the cylinder bore was rusty at the top.  Gotta bore that out.   New piston, rings etc.  

 

[dirtjumpordie]

On 9/11/2018 at 4:28 PM, adnohguy said:

R U going to Quit running Rotella now?

 

On 9/11/2018 at 6:24 PM, bork said:

Curious, why? is there some building evidence of Rot causing problems? I dont run it and probably never will. Just curious.

I started running rotella about 6 months ago.  Immediately after I started running rotella, the clutch started to slip.  

Then after about 800 miles, my valvetrain was completely destroyed just like in this guy's bike. 

Not saying the rotella is what caused it.  That engine had a lot of miles on it anyway.  Just sharing a relevant experience that I had with this same engine and that same oil. 

After the rebuild, I stopped running rotella.  I run Bel-Ray "THUMPER" 10W-50 now.  I don't care how much it costs.  I hate it when my bike is down.  Anything I can do to minimize down time, I'll do it lol.  Got about 4,500 miles on it so far and everything is still mint.

[greenjeans]

I may give the BelRay a go.  I've heard alot of good things about it.  I've run Rotella for years in my CB750s (the synthetic)  it usually goes on sale from time to time at my local autoparts store.   After dropping all this cash on this motor, I'm not gonna worry about an extra $20 for different oil.  

At risk of starting an oil war...  what do you guys favor as a break-in oil?

[JoeRC51]

10/40 like usual , nothing special is required.

[ricky racer]

Put some Zinc additive in your oil each and every time you change it! Most oils don't have this anymore and is needed. Never in my life have I suffered valve train failure due to oil on any bike or drag car/hot rod engine! Must have Zinc in the oil period for best results. Also I will add I have used Rotella in the past with zero issues.