valve guide vorn out

Hi the one who can help.
I am just about to restoere my commando 750 and I my question is in short, by which valve guide clearence is it nessesary to replace the guides? I have read that it on some new bikes must not exceed 0,005 mm play between shaft and sleeve.

You have got things mixed up!
0.005mm ? You mean 0.005" perhaps?

They should be around 0.002" (0.05mm) new and replaced if the clearance is greater than 0.004" (0.1mm)

I typically hone new colsibro (bronze) guides to 0.0015" Inlet and 0.002" Exhaust, replacing when they exceed 0.0025" Inlet and 0.0035" exhaust.

But I only do head work on competition engines and I have no experience of aircooled or Norton heads. So I would go with the official Norton figures I quoted above from the workshop manual.

Mike

www.racing-green.com if you want to see some of my head work.