Experienced engine guys...please check out.

englishwheeler · Full Member Joined: Nov 14, 2008 Posts: 47

Here are some pictures of my cam and rockers. I just took this off to inspect things to make sure everything's in good shape. I noticed a bit of discoloration on the cam and wondered if this is ok to use still. I got the bike with 7000 miles on it. I changed the oil and found it to have about 1 quart of old oil in it. I changed the oil and the engine sounded much better. The oil feed is great and supplying good oil. Any help is appreciated.

Shannon60

It looks as though that cam has suffered a lack of oil for a short time, but not terrably long I would reuse that as well as the rockers provided the rocker shafts are in reasonably good condition

englishwheeler · Full Member Joined: Nov 14, 2008 Posts: 47

I had a friend tell me the same, but I would rather hear that from XS guys. Thanks!

Retiredgentleman

I'm not an experienced engine guy, but I just recently opened up my top end, on an engine with 20,000 KMs. . Your rocker arms look the same as mine i.e. normal. Yes, that one cam lobe may have suffered some abuse at one time. I doubt that it would cause immediate problems, but its life may be shortened. Maybe 5twins will have an opinion for you.

pumps

Maybe inspect the rocker adjusters for pitting where they contact the valves? I'm not sure they would have any at 7000 miles though. A lot of the guys do the rocker mod where they swap out the stock adjusters for adjusters from a VW.
Read this: 650rider.com/index.php...t=elephant feet

You've already got it apart. 5twins is the guy to ask.

xsjohn · Last edited by xsjohn on November 24, 2008, 9:42 am; edited 1 time in total

Could buff the surfaces of that one lifter and lobe with some extra fine sand paper.......would check the oil pump and set the side clearance if it is out of spec ........years back I found mine to be .0035 and set it to .002 thou by measuring the impeller clearance when placed in the aluminun case with a good straight edge and feeler guage......had a post on that a couple of years ago...I'll see if Icanfind it....and maybe something pased throught the pump and damaged the impellers.......wouldn't take much since the clearances in the pump are "very" close..........

xsjohn

englishwheeler · Full Member Joined: Nov 14, 2008 Posts: 47

I knew you guys would help find the answer. Really appreciate it. I will check all the things mentioned here.

THanks.

Retiredgentleman

There's oil supplied to each cam lobe through a small hole in the rocker arm. Have you checked the passage way is clear for the abused cam lobe?
Perhaps you could try compressed air from the oil supply connections to be sure all 4 rockers have a good air flow.

Waldo

Your rocker arm photos show a trough running across, which is caused by the softness of the material, which is normal, they can be hard faced and reground, Mega cycle Cams, I believe. One rocker arm shows material being displaced perpendicular to that trough, that is usually an indication of gaulling(bad friction), if it is the rocker that is in contact with that ugly cam lobe, there is no easy cure, the damage is done and excessive wear will continue, time for a regrind on the cam or a new one, plus attention to the rocker arms. Do not use damaged rockers on new or reground cams, they will eat it up.

xsjohn

Waldo's got the right answer I would suspect......replace the damaged parts........

xsjohn

englishwheeler · Full Member Joined: Nov 14, 2008 Posts: 47

Where would I get new rockers? Or can I just address the contact surfaces? I've checked MikesXS and 650Central...they don't have rockers. Maybe try and buy a whole valve cover off ebay...but that'a gamble just the same as buying a used bike.

Waldo

I got mine done at www.megacyclecams.com, they were hard faced and ground, $64.00 each, but they will last, with no more little groove appearing like you would get, even with new rockers after a period of time.

Waldo

englishwheeler · Full Member Joined: Nov 14, 2008 Posts: 47

Thanks a lot. I'm going to look into that.

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