Tappet clearances

[Cooper1999]

From memory (never the best), standard tappet clearances on a 1275 are 0.8mm cold.
What should they be with 1.5 roller rockers fitted?
Thanks.

[colin_p]

Whatever the standard is, multiply by the rocker ratio, i.e. 1.5 in your case assuming it is a standard'ish cam. A high lift or longer duration cam might need some proper research and or advice.

And wash your mouth out, MM's

Should be in "thou" on the hallowed A series


From my even foggier memory, I recall the inlets at 15 thou and exhausts at 20 thou.

[TRIUMPHBULLET]

Be careful of clearances being too large if you have needle roller rockers as it can cause them to fail, plain bearings should be ok with standard clearances.
Google 'roller rocker bearing failure', plenty of information about.