Max Bore on 1608

[helebah]

G'Day GC,
The class regulations I run my 125 in allow up to a 1.5mm increase in bore. What is a sensible max size bore achievable on a 1608 block. I am looking at getting a set of forged pistons made.

Thank you
Graham

[Guy Croft]

That is more governed by the bore of the aval gaskets, I suggest you stick to 81mm..

GC

edited 2nd Jun by GC due to typo

[helebah]

Guy,
With the 1608 being 80 mm bore, does the comment on gasket bore size still aply??
thank you
Graham

[S&B125]

G'Day Graham
I also run a 125T and recently swapped cylinder heads for the first time since purchase. I found that my engine was @ 81mm bore and then had grave concerns that the gasket set I had would have an 80.6mm fire ring as they mostly had. I was delighted to find that the Goertz gasket in the very recently purchased top set had an 81mm fire ring so all was well.
So I'd go with 81mm bore as Guy suggests.
I'd like to compare notes with you sometime because we seem to be at similar points with our cars.
Regards
Steve

[Guy Croft]

Sorry, typographical error, I meant 81mm bore on the 1608,

GC