engine noise

[dolt]

Or, just get a mechanics stethoscope for about $10; much better than the screwdriver or steel/wooden rod method but still hard to isolate an internal noise. Should be able to at least isolate the noise source from top end, lower unit, cam chest or primary. Early compensators are not known for failing or making noise like the later compensators; however, if the Bellvill springs get weak, they can become noisy but I doubt that is the source.

 

[nascar7613]

I began taking the parts off to remove the front head. After I removed the intake manifold and looking through the intake port of the head, I could see a shiny area about 1/8" long on the intake valve stem below the end of the valve guide. The valve guide is being pushed upward towards the top of the head. There is a gap between the lower valve spring collar and the surface of the head. I believe that is the cause of the noise, but what would make the valve guide push out.

 

[CHZWIZ]

Maybe the valve is bent. You will have to take it a part and examine everything. Does it look like the piston made contact with the valve?

 

[dolt]

I began taking the parts off to remove the front head. After I removed the intake manifold and looking through the intake port of the head, I could see a shiny area about 1/8" long on the intake valve stem below the end of the valve guide. The valve guide is being pushed upward towards the top of the head. There is a gap between the lower valve spring collar and the surface of the head. I believe that is the cause of the noise, but what would make the valve guide push out.

Several reasons none of which really matter at this point; pictures would help. Pull the head and get a closer look.

 

[Jack Klarich1]

Replace the guide, use some loctite

 

[nascar7613]

Sent the head to the machine shop, they said there was nothing wrong with the valve guide or anything, fuel wash shined up the valve stem. Pulled the jug off and bam, there it is, the wrist pin had come out the side of the piston.

 

[tourbox]

Oh boy; sounds like your work is cut out for you.Usually the gouge is to deep to bore and a new cylinder/piston required. Maybe just upgrade to a '95 w/ cams, if it is not already.
tourbox

 

[dolt]

Bore might cleanup at 3.875", that's a .125" over bore and 95". If that won't clean it up maybe 3.938" which is.188" over bore and 98". Plenty of pistons available, CP and Wiseco. A piston with a small dome, like 3cc with stock chambers will make a big difference even with stock. Just and FYI, roller rockers make more noise that stock rocker, so if you want to reduce valve train noise, relace the rollers with the OEM rocker arms. Fueling lifters have had problems, better choices available. You did not say whether the bike is EFI or carbed but the cams are not the same. EFI cams close at 34* but carbed close at 38* which will make a difference when setting compression on the rebuild.