GS 750 to GS850?

[Guest]

Ok, keep in mind that I'm 100% new to cycles and to air cooled engines but...

Are the GS750 engines and GS850 engines in the same family and if so can you swap pistons and the upper end and make an a 750 into an 850?

I've searched some and not seen this mentioned and with the type of tinkering and level of genius around here this leads me to think it can't be done...but its worth asking.

Mac

83 GS750ES (headed for the road)
84 GS750ES (Complete, Clean and Canadian parts bike..anyone have a frame?)
Unknown year GS750 16v engine to play with.

[Dink]

A 16 valve 750 motor will not accept 850 barrels and pistons to the best of my knowledge, I believe you could if it was an 8 valve 750 motor though.
Having said that Wiseco do an 844 big bore kit for the 16 valve motor. :twisted:
Dink

[robinjo]

I have read that it can be done if you swap the head too.
A 844 cc 16v would be MUCH faster though.

[Macmatic]

Thanks for the feedback.

I figured it could't be that easy but its what I do with all my cars.....out with the 2.1L block and in with the 2.3 and better flowing head. Good for a fair boost in HP a lbs/ft any day....now if I can just find a better intercooler....

Mac

[KW]

850 will fit onto the 8 valve 750 i.e. the '76-'79 GS750.