De-stinking Penelope

[rustybronco]

Chuck, Ivor went through four camshafts before he found a good set. This one had an under sized cam @ 22K miles. Who knows how many else go undetected just because they look good upon casual inspection.

It takes time to do all the inspecting and measuring. That's something you wouldn't normally have to do on a bike with a known history, much less one that's had metal rolling around the inside of it.

[chuck hahn]

I not rushing you..I totally get it. I was just saying that back in the day there was all kinds of crazy stuff like what my dad said about the GM plant going on and its still happening to this day. I have the factory service manual and will check the lobes when I go over to Randys to be sure I send you a good one.

[Nessism]

Chuck, Ivor went through four camshafts before he found a good set. This one had an under sized cam @ 22K miles. Who knows how many else go undetected just because they look good upon casual inspection.

I've had some worn camshafts too. It happens, maybe because of the GS low pressure oiling system, and all the heat in the head. At any rate, camshafts are cheap enough, but the trick is to find someone that can measure them before you throw down your money.

Oh, and I suspect about 90% of the people don't bother to measure stuff like this...and that cam would run just fine the way it is. Sometimes we (me included) make more work for ourselves because we know too much.

[rustybronco]

I know your not rushing me, it was just me talking out loud while I was trying to make some sense out of why the engine is like it is.

Back to checking transmission bearings...

[chuck hahn]

Who is Ivor?? Its like this probably because of a few possibilites. 1)..may have gotten gas in the oil and the PO(s) didnt know anything about how to look for things and it got spun with bad oil. 2)..was run hard on a low oil level. 3) was one of those Jethro types that would rev it at 12G in neutral all day long to impress his friends with "how badass my bike is".

[rustybronco]

Sometimes we (me included) make more work for ourselves because we know too much.

Or, have a tendency to over think things at times...

I wonder what 'this' cams lobe would measure on a hardness scale?

[rustybronco]

http://thegsresources.com/_forum/member.php?u=6290

Or, the camshaft was just plain too soft from the factory.

[chuck hahn]

How would you find out what the factory Rockwell standard was???

[rustybronco]

I don't know if you could find out what it was from the factory. What you could find out is what the cam manufacturers of today use for hardness and compare that to what you have.

The reason I suspect improper heat treatment of both cams, is because the camshaft bearing journals look good, indicating proper oiling, a small bit of metal transfer to one of the shims and both camshafts appear to being close to the limit.

Let's not forget the small block Chevy camshafts of the same era, which were prone to having soft lobes as well.

[Matchless]

Thanks spyder! My wallet thinks it's quite the project also.

Dale,
That is one even I can understand!
Dale, just take your time, its not your only ride! The rebuild is usually a most enjoyable time anyway, so stretch it out if you can.
Even if it takes you 5 or 10 years to complete, so what! As long as you enjoy fiddling with it.

[rustybronco]

Andre, I might tend to agree with you... if I was in my thirties still!

I'd really like to ride it while I still can

Even if it takes you 5 or 10 years to complete, so what! As long as you enjoy fiddling with it.

[chuck hahn]

Never knew that about the cases being machine matched I always thought they made X thousand lowers and uppers and what ever one was grabbed from the lines were married..Hmm. Is this due to nesting issues with the bearings??? Seems a very slow process to mill one set at a time custom..

[Spyder]

Thanks spyder! My wallet thinks it's quite the project also.

I'm sure of that. Just think of the millions you're gonna make remanufactuing gauge clusters. Lol...

[Dogma]

Never knew that about the cases being machine matched I always thought they made X thousand lowers and uppers and what ever one was grabbed from the lines were married..Hmm. Is this due to nesting issues with the bearings??? Seems a very slow process to mill one set at a time custom..

This is close to my corner of the world.

It might be slow, but it's often the only way to achieve sufficiently tight tolerances between mating parts. Anyhow, back in they day, the cases would have each gone through a couple machines before they were done. NC machines weren't very common yet, so a lot of setups on simple machines was more common for a part's process than fewer setups on more flexible machines. Besides, once you have a worker marry the parts up (in a jig it's probably a 30 second job or less), the two parts would finish at the same time. On the whole, it probably wasn't such a burden. In fact it might have been easier, because whole bores are easier to cut than half bores.

[Spyder]

I can't tell ya how many early 80's 305's I have come across with a flat cam lobe. Usually an intake lobe.