Crankcases 1967 Atlas vs G15CS?

Ludwig,

You got the lettering on the timing side case horizontal. Real nice. I am impressed, and I didn't mean to sound like I wasn't if my comments came off that way. I wish I had your metal working skills. I'm sure that bike is a pleasure to ride.
 
It is an 850 Commando case.
Although I am the original owner of what is probably the last hybrid ever produced (132xxx), the only original parts are
the gearbox shell, fork yoke, oil tank cover and tail light lens.
Over the years, EVERY other part has been modified or changed to make it a practical and reliable touring bike:

Crankcases 1967 Atlas vs G15CS?
Hi Ludwig,
That is an extremely beautiful bike.

You say that the oil tank is non-original. What is it?

Also, how is the engine vibration, not being rubber mounted, Iassume?
 
..Look at all those damn primary bolts (14 to be exact) in that AMC outer primary cover..
plus disconnect the alternator..
I see you added a plug to strobe time the ignition?
I did the same when I still had the original cover.
 
You say that the oil tank is non-original. What is it?

Also, how is the engine vibration, not being rubber mounted, Iassume?

The oil tank has an internal cooling channel, cooling fins at the back, external dipstick, etc..
Not the engine, but footrests are rubber mounted, dampers inside handlebars, JS lighter pistons+ longer rods..
All off-topic.
Sometimes I play with the idea to start a thread about the bike and its modifications, but I'm afraid it will take too long.
 
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plus disconnect the alternator..
I see you added a plug to strobe time the ignition?
I did the same when I still had the original cover.
I've got an almost on topic horror story about that stator wire, but I wrote it up and it's too long and barely on topic.

Yes, I put that hole in the outer primary so I could strobe the ignition. Filed a grove in the stator resin at 32 degrees BTDC and painted it. Real cave man technology. I need to check the timing. Thanks for reminding me. Just tried it and my fancy timing light wasn't interested. I'll have to dig out Sun timing light I've had for 50 years and try again.
 
Hi.
I can only agree with Dyno Dave said.
Add that all the hybrids G15/N15/33/P11 have the same crankcases.
Commando, neither early, never had separate stator bracket of Atlas; sure my very early 68 commando doesnt have.
Piero
 
Hello all,
Can anyone tell me what the difference (s) are between the 1967 Atlas crankcase and 1967 G15CS crankcase? I see they have differing part #'s: Atlas- 25374 and G15CS-25375.
I am particularly interested in what differences there are on the drive side. Inner primary case mounting hole orientation? Machining to fit inner primary case front hole diameter?

Any info from @dynodave or @pierodn will be appreciated.

Thanks,
Ed
The crankcasing is machined differently to fit the AMC chaincases and Atlas chaincases are not interchangable.
 
Do you or anyone have photos of this difference?


Just put the cheque in the post, Bernhard :)
 
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