Get out the straight jacket

worntorn said:
It seems that an extra few hp can be very costly to find, even more costly to keep!

Ive got standard lifters in an alloy barrel for the 920. A standard but nitrided nos stock cam is lifting them.
Cost was very low, but I wonder if the alloy tunnels will hold up. I guess you have that concern too.


I recall that G81 was investigating this, not sure if he came to a conclusion or just dropped the plan to build alloy cylinders and left that with Andy Molnar.

Glen
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Total waste of money on a street bike, but I only have one left, and only a few years left, so what the heck, why not do something foolish.

Yes, I wondered about the tappet bores in the alloy barrels, but they seem sturdy enough to outlast me with the stock tappets in them. That is not what is in it now though. Touched up by me JSM Triumph lifters and Triumph blocks are in it.

If I have bronze metallic in my oil when I drain it again, I'll ride till it starts making noise, then tear it down and decommission the remaining JSM parts. Stock flat tappets will be used in the alloy barrels. Not sure about what cam I would use. I don't really need a hot rod cam anymore.
 
I don’t believe Maney barrels have a reputation for wearing out the tappet bores. I think that provided things stay clean, they should be fine. It’s a large, low stressed and well lubricated surface area.

The problems arise if crap gets in there. My iron barrels tappet bores were shot, very heavily scored. It looked fairly obvious to me that a PO had got carbon or gasket detritus down there which had gradually turned itself into a horrid abrasive paste!
 
Fast Eddie said:
I don’t believe Maney barrels have a reputation for wearing out the tappet bores. I think that provided things stay clean, they should be fine. It’s a large, low stressed and well lubricated surface area.

The problems arise if crap gets in there. My iron barrels tappet bores were shot, very heavily scored. It looked fairly obvious to me that a PO had got carbon or gasket detritus down there which had gradually turned itself into a horrid abrasive paste!
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Don't forget good old SAND.
From head gasket changing.
 
baz said:
"Sand"?
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The front wheel kicks it up for thousands of miles.
It ends between the fins.
Slight oil seepage residue holds it tenaciously in there.
Inexpensive pressure washers were not a thing 40-50 years ago.
I have seen cylinder heads removed without even a quick blast of compressed air to clean.
I see them stacked up in the que for the machine shop, with sand still attached at the part line.
The mechanics at the dealership were under time constraints.
Attention to detail, is one of the many attributes that differentiates a mechanic from a parts changer.

My lifters bores were scored from FOD when I got the bike as well.
 
+ Road grit from endlessly draining the sump and dumping road grit from engine bottom back into the engine.

Glen
 
I would imagine many change spark plugs without using compressed air around the plug before taking the plugs out. The off the road crap that falls into the cylinder bore wouldn't hurt the tappet bores, but just another example of details.

I did not have to do anything to the Molnar parts other than clean them.

Another high quality JSM part example...

3X this crap was in the points/ignition end of the JS2 cam. I'm surprised I caught it being a parts changer.

Get out the straight jacket


Has anyone seen this kind of swarf in the end of a cam sold by Andover or JC?

I stopped taking new cars I purchased back to the dealership for anything other than recall in the early 1980's. Same with motorcycles. Master parts changer.
 
concours said:
The front wheel kicks it up for thousands of miles.
It ends between the fins.
Slight oil seepage residue holds it tenaciously in there.
Inexpensive pressure washers were not a thing 40-50 years ago.
I have seen cylinder heads removed without even a quick blast of compressed air to clean.
I see them stacked up in the que for the machine shop, with sand still attached at the part line.
The mechanics at the dealership were under time constraints.
Attention to detail, is one of the many attributes that differentiates a mechanic from a parts changer.

My lifters bores were scored from FOD when I got the bike as well.
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I sure hope you aren't saying that most Norton twin head gaskets leak, because that has been vehemently denied !
Mine are both completely dry, other than some oil seepage, which is a totally different thing than a leak!:)

Glen
 
worntorn said:
I sure hope you aren't saying that most Norton twin head gaskets leak, because that has been vehemently denied !
Mine are both completely dry, other than some oil seepage, which is a totally different thing than a leak!:)

Glen
Click to expand...
Lol, I know.

These bike were not always bedazzled, jewelry festooned, climate control kept, enclosed trailer toted, doted & fawned over, runway modeled, over-restored princesses.

At one time, they were just motorcycles.
Ridden hard, put away wet.
Some even got (😱) abused, neglected and worked on by NON-NASA flight engineers.
🤣🍻🤡⚙️⚒️
 
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gortnipper said:
Look at a Webcam 312 from Jim. The 312a I got from him was jewelry.

www.accessnorton.com

Cams (2012)

Taking "man cave" to another level :D
www.accessnorton.com www.accessnorton.com
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Things are going well audibly so far with this version of the motor. Another 125 miles and I'll look at the drained oil, but I think my mods to the lifter blocks and dressing out the edges on the lifters helped. I do hope so. As much fun as it is working with my old hands, I was not looking forward to doing this engine again. Thanks for the thoughts about a cam.
 

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