125 cc head on a 150cc

[dadof2]

i was thinking about putting a 125cc head on a 150cc
both engines are lifan
has anyone done this ,the theory i have behind it is like putting a holden 173 head on a 202 increasing compression ratios

 

[MiniFighter]

theory is correct, thing i'd concerned about is the large jump in cc size? Maybe try a 140 head first?

I could be way off just the first thing that came to mind?

 

[dadof2]

i have a spare 125 head, i was thinking swap the cams so im not pushing a vlave out more or less
but what about timing chain will it affect that

cheers for the reply minifighter

 

[sean01]

should bolt straight on if it is a china crf pattern head.. but use the 150 cam as they have better lift and duration.

also check the piston wouldnt hit the head..

 

[dadof2]

cheers sean
i try have it done throughout the week and post the results good or bad