Scrolling a combat camshaft

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In another forum Dave Comeau wrote about 06-2600 cam bushes " IMO avoid the 06-2600/06-2601 system at all cost, if you have a "plain bush" cam then get it scrolled, or scroll the later bushes."

I like the idea of getting my unscrolled combat camshaft scrolled, but who can do this...anyone?
 
illf8ed
#1. The biggest concern for the combat era cams were the bronze washers with the tab that mated up with the beveled cam thrust washer. These little tabs have been known to break off and get sucked up into the oil pump :shock: which runs into design flaw #2 coming into play when the engineers removed the large oil sump :shock: :shock: and did away with it during the 72 year bikes. Mick Hemmings recommends breaking off these tabs for this type engine/ bushing setup. Most show the crack in the bend from manufacture process anyway. Why these changes were made is beyond me. Probably driven by bean counters trying to save a pound here or there.
Cheers,
Thomas
CNN
 
illf8ed said:
In another forum Dave Comeau wrote about 06-2600 cam bushes " IMO avoid the 06-2600/06-2601 system at all cost, if you have a "plain bush" cam then get it scrolled, or scroll the later bushes."

I like the idea of getting my unscrolled combat camshaft scrolled, but who can do this...anyone?

I will be glad to scroll your cam. Jim
 
Both my Combats had lost thrust washer tabs when opened to service and found oil pump damage, chipped teeth and scored sides on my 1st one but still kept pressure up enough. Ya don't need to scroll the cam shaft though as can easier scroll the cam bushes or fit the dual kind on DS so a pocket of oil forms between. For fun I grooved case walls a bit and funnel opened the holes for some help oiling. Combats can't wet sump too much into damaging levels just messy if run into elastic engine rpm, as the low down breather returns oil to tank faster than oil pump can. If extra time money to burn might consider dry friction coating.
 
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