Hi All,
I have been picking up useful information from the forum for years but this is my first post.
I bought a rough looking bike on Ebay a few years ago knowing that there was a majesty under all the alterations and rust. I took the head of to check if the bike was a 250 or a 320, the bore measurement was 70mm so i assumed that it was a 250. On further investigation the left side crankcase was broken so i managed to find a new replacement on Ebay. Yesterday was the first time i have been able to put the old and new crankcases together, and i noticed the opening on the old case for the cylinder sleeve is larger than the new case. Am i right in thinking that the 320 engine was opened up for a larger sleeve diameter? Photo's attached.
Thanks !
Andy