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- Aug 10, 2014
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just trying to put all major available info in one spot, i'll add more as it may come,
what i understand for cranks is rebalance is required for commando use and the end keyway offset is not the same which gets into some 'setting the timing' issues, but, other than that, good to go
not quite clear on barrels & heads, or cases,
on barrels, prior threads
https://www.accessnorton.com/search/814776/?q=atlas+barrels&t=post&o=relevance
with this jumping out
https://www.accessnorton.com/NortonCommando/atlas-barrels.13115/
atlas cyl heads are oiled from the top vs commando heads from the sides, haven't come across further info getting around that? or use with commando barrels?
dunno about atlas engine cases, whether they can be mounted at the forward angle commando position, or adapted for the commando primary drive covers setup? the ignition & tach drive is also similar to the fastback setup
i'm sticking to 750 here, from what i understand, the 750 head isn't a bolt on to an 850 engine due to fastener spacing diffs
what i understand for cranks is rebalance is required for commando use and the end keyway offset is not the same which gets into some 'setting the timing' issues, but, other than that, good to go
not quite clear on barrels & heads, or cases,
on barrels, prior threads
https://www.accessnorton.com/search/814776/?q=atlas+barrels&t=post&o=relevance
with this jumping out
https://www.accessnorton.com/NortonCommando/atlas-barrels.13115/
so, given the above, altho perhaps doable, a main issue being small margins scenario for sealing & head gasket issues(?), i also haven't found any solid info on atlas barrel use in commando engines?1965 was the last year that all heavy production got the spigotted cylinder, 500cc, 650cc and 750cc.
I have heard of re-drilling and tapping the Atlas cylinders with the 5/16 head bolts to take the 3/8" Commando head bolts, but if you look between the fins on both an Atlas and 750cc Commando cylinder you will see that the Commando cylinder had a lot of material added in there for the bigger head bolts to anchor in, the Atlas was pretty skimpy in this area.
The 500cc and 650cc engines had the 3/8" bolts just like the Commando, it was just the Atlas that had the small diameter head bolts.
atlas cyl heads are oiled from the top vs commando heads from the sides, haven't come across further info getting around that? or use with commando barrels?
dunno about atlas engine cases, whether they can be mounted at the forward angle commando position, or adapted for the commando primary drive covers setup? the ignition & tach drive is also similar to the fastback setup
i'm sticking to 750 here, from what i understand, the 750 head isn't a bolt on to an 850 engine due to fastener spacing diffs
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