combat barrels Vs normal barrel?

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interstateOz

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hi there, just needing to know is there a difference in the combat barrels vs the standard, i was told by a friend who knows nortons that the combat barrels were factory skimmed which made the compression higher, but have been told (in the for sale section) the barrels were the same and only the heads were skimmed/shaved at factory to increase compression, can anyone shed some light :D thanks
 
All 750 Commando barrels are the same. Only the head was shaved on the Combat. Atlas/G15/N15/P11 barrels are the same as Commando except for 5/16 cylinder head bolt holes.
 
interstateOz said:
just needing to know is there a difference in the combat barrels vs the standard
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Yes, Combat barrels were black and standard barrels were silver! :wink:
 
interstateOz said:
man do i feel silly :oops: thanks for the info though!
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Don't feel silly. Now you know more about Nortons than your friend who KNOWS Nortons.
 
NORMAL barrels?
early 750 vs later
I believe short barrels to raise the compression is strictly an irreversable aftermarket/field bodge.
the combat and later barrels are different.
The lifter spigots are machined shorter...so the high lift 2S cam will not foul the barrels (lifter spigots)
 
Ron L said:
All 750 Commando barrels are the same. Only the head was shaved on the Combat. Atlas/G15/N15/P11 barrels are the same as Commando except for 5/16 cylinder head bolt holes.
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Ron don't forget that some also was spigot ed to the head.
 
And I just wanted to confirm then all 750 cylinder heads are the same factory over all the years it's just the combat head that's different, or is there any differences between the early and later ones? Thanks
 
interstateOz said:
And I just wanted to confirm then all 750 cylinder heads are the same factory over all the years it's just the combat head that's different, or is there any differences between the early and later ones?
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There were at least four different 750 heads.
 
Another little barrel detail I learned about 750 barrels, is they all were cut at a slight slant on top of .003". Mainly affects head steady mounting angle for the anal to worry.

The early CHO Combat heads were hand ported in Wolvenhaven and ended up over ported until they got their act better in casting smaller/better sized 32 mm ports.
At least that's what I'm told and backed up by my head builder Michael Starkey of British Toys in NC, also commented how large the ports were inside when he took casts of them.
 
I think thats the place if mis spelled, correct me please, but Peel CHO head was messed with in the ports, too much till 6800 rpm, then another piston kicked in.
 
Hi guys- so, how would I go about determining if I own a Combat or a standard Commando? It's a 1968. Black barrels. Runs like a scalded ape, really pulls. Your wisdom is welcome, thanks!
 
From what I know if it's an original 68 it won't be cause combats were only in 72, and there's a 'C' stamped on the top of the head :)
 
Didn't find no C on top of my 2 heads but did find CHO on bottom of Combat heads.
Main difference is 32 mm ports and less meat/distance between head and barrel fins when mounted.
 
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