Replace cams as a pair only?

[paulincayman]

Hi 
Are there any mechanical reasons for not changing camshafts as a pair ? I have a set of A11s which I am considering fitting to the 3CL.  Two of the exhaust lobes are worn to some sort of a blunt point , the third is still nice and round. The inlet cam appears  perfect.  I was thinking of replacing the exhaust  cam only.? Is that a bad idea?
Thanks
Paul

 

[piranha-bro2]

No mechanical or engineering reason I can think of that would necessitate changing both as a pair. A cam is a cam. If one bucket was worn you wouldn't replace all six ...

Can you ascertain why the ex cam is worn?

 

[paulincayman]

Neither could I, but as this is my first dohc bike I thought I ought to ask. The cam was supplied with a bunch of odd spares so not from this engine so  I'm not too concerned on that score. Would be interested to understand why though. Maybe from an early head with sinking valves?

 

[Laverdalothar]

I even went for just replacing the A11 Inlet with a 4/C Inlet. Ran the bike like that for about 20.000km without issues and changed the Exhaust Cam to 4/C later on. No issues at all. Just make sure the timing is right...