From:Russell Hughes e-mail:russellhugheskj@yahoo.com
Subject:RE: RE: RE: Norwegian Henderson oddities - patch on top of g-box Date:Fri Dec 19 23:32:48 2008
Response to:2258
First the small side "K style" cover on the transmission. Most all machining processes have trade offs. The following is a discussion of the dynamic balance or strugle between less casting and more machining or more casting and less/better machining:
Align boring the countershaft bearing pedistals is most accurately and easiest done when the boring bar is held from both out sides of the trans case as was the process on the earlier bikes. But if done correctly this requires additional pattern cores equating more time and expense in the foundry but less expense machining.
The inverse as with the KJ is less work at the foundry but more at the machine shop. This blind hole procedure requires the boring and facing tools to be held at the end of an unsupported quill/spindle. This is where the bean counters get pulled into the bussiness. Which way cost less??????
Now for the mystery part. I have seen a good number of broken old cases and maybe a few new ones straight from the sand. I have not seen any need for additional support in this area where the slug is. Additionally the part has no physical characteristics that indicate factory design, so I don't know what it is but I bet it was done on a weekend.
There is a little known chaplet in these cases located close to the sprocket bearing area but nothing like the part in the pictures.
The upper case is a WEAK PART BY DESIGN, it is the pan that is the back bone of the engine. It was common for the factory to weld repairs rather than scrap cases. This looks unlike a factory repair. Enough of my rambling, Russell.

----- ORIGINAL MESSAGE FOLLOWS -----
I don't know for sure but is this the area where the sprue* was located? (Any ideas Russell?) I have seen several cases which show signs of being attacked with an angke grinder in this area. Maybe somone got too enthusiastic and took off more than they should. Having said that, I guess the factory would have welded on reinforcement rather than bolt on a patch. Steve
----- ORIGINAL MESSAGE FOLLOWS -----
Another pic

----- ORIGINAL MESSAGE FOLLOWS -----
Having followed the K threads with great interest I would like some help with a friends De-luxe 1922, engine number D 1876.

This have the later type De-luxe seat mount plate, but the plate is fitted with the K style trough frame bolts. It seems there have never been any U clamps used as there is no mark on the frame that indicates this even if there are holes in the plate for the u-bolts, there is neither marks in the plate from where the u-clamp nut would have been.

OK, then there is a strange little aluminium piece screwed onto the upper case to strengthen it in the area between flywheel and gearbox. This have a very nice fit and does not at all look like home made even if there is no part number casted in it. Have anyone ever seen this before? Was this a mod that where common practice in the old days?

There is also another thing wrong according to the De-luxe parts list. There is the K style little cover for the gear shaft on the upper case. This is not supposed to be there on De-luxes as far as I know?

Finally one question regarding my 1927 De-luxe. This have had the a priming cup on the inlet manifold which I admit could easily have been a owner mod. It does have a mod that is more advanced to the manifold though, there are three studs in the manifold cast, to where a stylish little cover is attached. See enclosed photo. Is this some known periodic accessory?