Horizons Unlimited - The HUBB

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steveloomis 9 Oct 2013 19:26

Sounds louder on the right side. Did you grab ahold of the compression release lever on the rocker box to see if it was being tapped?

jjrider 9 Oct 2013 22:43

That one came through a little better on my laptop, It does sound like rockers, but real bad rockers. Rather tinny sounding though instead of a more knock. I imagine a real loose rockers would make such a racket. I didn't see the comp lever moving at all in that video so that may not be it. Definitely make sure your on the compression stroke when adjusting. If your at the wrong TDC, the intake valves can be checked and adjusted because they will be closed, but not the best way.
To verify your on the right TDC, look through one of the exhaust valve ports(those round caps in the valve cover). With a socket on the crank turn it CCW while watching both for the "T" and the exhaust rocker inside that port. If that rocker is down or moving as you near the "T", that is the wrong one. go one more revolution to "T". All your rockers should have a little play in them when you wiggle them with a finger. You are loosening the nut first on the rocker, then slowly turn the "bolt"(with the slot), when the feeler guage just drags but not stuck, hold the bolt still, while snugging the nut up.

Did you squirt any oil as it is running to see if things quiet down at all?

ajax 9 Oct 2013 23:39

Thanks guys
The first time i adjusted I'm pretty sure I was on the wrong stroke. The second video was I think correct. So I had top end noise at 3 stages now.

!st without adjustment,
2nd which is the 1st video (1st attempted valve adjust)
3rd adjusted i hope correctly 2nd video

All 3 times have the same sound maybe different volume but not sure.

I started taking the rocker head off (bike has over torqued bolts and rounded heads all over.

One thing I noticed is the decompress lever looks knocked on the edge. Could be normal wear and tear or its getting beat up. Uploaded pictures
Flickr: gregcappello1's Photostream

ajax 10 Oct 2013 01:37

rocker head is off
chain looks good, not loose
cam looks fine, no marks
valves all at same height, all look the same
plenty of oil up top

Rockers all look good, no obvious wear by sight
there is very little movement side to side but slightly more from decomp exhaust valve (not much difference really)

The only thing that is obvious to me is the decomp side exhaust valve, the tappet when compared to the other side would be turned out further making a loose valve.

I'll upload video in a bit of rockers

ajax 10 Oct 2013 01:53

video P1060127 | Flickr - Photo Sharing!

steveloomis 10 Oct 2013 02:50

The face of the right exhaust tappet looks worn. Everything else looks normal. Does the rocker arm appear to be straight? From the pics it could be bent a little. Still not sure where the noise is coming from. Is there wear marks on the rocker arm where the compression release arm touches when engaged?

jjrider 10 Oct 2013 03:44

My windows 8 pos computer wouldn't open the video but the decomp looks normal for wear from a 30 year old bike, with that amount of noise it really should be something obvious I would think. I can see the rocker faces and they look normal.

ajax 10 Oct 2013 04:56

Their does not seem to be any high wear. when I put the decomprs lever back in, it lines up. Nothing indicating stress as well.
Rockers all move with same range, right exhaust moves with slightly less resistance. The valves, chain and cam all look good.

jjrider 10 Oct 2013 05:16

Try wiggling all the valves and springs themselves , just to see if anything seems loose. I'm kind of at a loss then. The noise couldn't be coming from down lower, it has to be up top.
Do you have an air hose? A person can put air pressure into the cylinder and see if any air comes hissing out a valve to find maybe a broken seat or bent valve, but I really don't think thats a high probability. But you never know, it did show up all of a sudden and after it was shut down, then started cold.

ajax 10 Oct 2013 19:00

checked valves and springs and all were identical. Nothing looses
Trying shooting air in spark plug hole nothing unique.

I have kawabond, does anyone no if this is a good alternate to yamabond?
If its good it saves me a trip :)

steveloomis 10 Oct 2013 20:46

I do not know about Kawabond. Is it a grey color? I suspect it is the same. Similar name, Hondabond is about the same etc... Permatex Motoseal grey is about the same, used it with success as well.

ajax 16 Oct 2013 23:22

Everything is all back together and noise remains
Real pain in the a.. getting the rocker head off and again finding more over torqued bolts.

Found no obvious problems when head was off so I knew the noise would be back.
I even pulled out the decomp lever when it was running. Made a mess with oil but noise unchanged.
The sound is definitely top end, sounds strongly like tappet. When the valves have play at the compression stroke I can mimic the sound (basically) by tapping the rocker down.
Tomorrow just for a trial I will tighten valves up a bit to see if their are changes.
Thanks for all advice
Greg

steveloomis 17 Oct 2013 00:24

I remember a post awhile back, maybe another forum. The guy did all you did and nothing. He finally pulled the head and found one of the valves was actually just touching the piston because the piston was a bit loose in the bore and rocked enough for the valve to touch it... He bored, fitted a new piston and all is well. You certainly should not run it "anyway". Pulling the head is only a bit harder than the rockerbox and you will need a new head gasket and other seals etc.

jjrider 17 Oct 2013 00:59

There was one also like steve said that the piston was just touching the head at the squishband and causing a knock. When the head was pulled you could see slight marks on the piston edge and head. It was barely shinny. I would maybe do like you said, tighten them up to .002" clearnance and see if any changes. There has to be just one stupid little thing doing this.

ajax 17 Oct 2013 01:30

The top end was rebuilt (new piston) I would imagine not that many hours ago (2011) as the bike was not road legal. Now people sell for a reason so perhaps that was a problem. I will tighten up the clearance to see if their is any change.
Just sounds like tappets hitting but if my test at tight and loose shows no change then I'll have to take a look at the piston.
If it was a problem with the valve hitting the piston would it sound like loose valves? Also I would think the valve would of bent, maybe loss of compression? I just don't see signs of that.


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