Z1E vz Z1R Head Differences?

Hiya guys

Hoping for some expertise to confirm. i bought a Z1R1000 many moons ago and made the mistake of not properly identifying engine/frame. The frame is genuine Z!R, but the engine is a Z1E kz900. Im getting all the components together to build a genuine Z1R engine, can someone tell me whether the heads are exactly the same between these models please?

Many thanks

Snowy

Pretty much the same except exhaust studs are 6mm on the 900 and 8mm on the Z1R.
900 head can be drilled to take the 8mm studs.
Valves , combustion chambers etc are all the same size and it's a straight swap.

The obvious difference is the engine case serial number.  A 76 engine begins with Z1E, while a 78 or 80 engine begines with KZT. Also, a 78 or 80 engine will have a second plate, near the kickshaft.  The 76 engine has lettering on the actual case, or in some very early instances...nothing.  An 80 engine will have 16 teeth on the crank and 32 on the cams.  A 76 engine will have 15 teeth on the crank and 30 on the cams.  I believe the 80 engine is a MK2, which means two braces on the cases behind the serial number plate.  Many of the engine components have date codes stamped on them somewhere, usually in a non visible location.

The barrels on a 76 engine will have 900 cc embossed on the lower right side.  A 78 or 80 engine will have either 1015 cc or 1.015 l.

The carbs on a 78 Z1R engine are 28 mm non pumpers.  I'm not sure what's on the 80's...28 mm for sure but maybe pumpers.