PE Vs RM Cylinders

[TM BILL]

Is there an easy way to identify an RM 250 cylinder and head from a PE cylinder and head other than the rubber blocks in the PE cylinder ?

I would appreciate any help on all years as i have a number of cylinders and heads and im not sure whats what 

[vmx42]

…i have a number of cylinders and heads and im not sure whats what 

Come on Bill, I have seen your filing system and I can't understand why there is any confusion [unless Beer was involved?]. It all seemed perfectly logical to me…

[Davey Crocket]

 

[oldfart]

Bill ,  a  PE 250 80/81  Vs   RM 250   1980 .    difference is rubbers .....as i did a bit of research 2 years back.

[LWC82PE]

Part # = 11111-40301
Part Description = HEAD,CYLINDER
Model Count = 7
PE250T 1980
PE250X 1981
PE250Z 1982
RM250-N 1979
RM250-T 1980
RS250T 1980
RS250X 1981

1980 PE250 has same barrel as 79/80 RM250 except has the rubbers as oldfart says and the the 81/82 PE250 barrel is different part number because the barrel finning is different and has different rubbers to the 1980 one.

With the heads, some of the the earlier pre 80 ones use a round head gasket and later use one that fits over the studs and the head studs are raised and engage with cut outs in the head.

If you can post photos im sure we can work out what you got.