Scooterotica

Im looking for an oversize 71mm piston for my cast linered RB .
Could someone tell me the gudgeon pin diameter of the yz piston ,and a conrod thats suitable to use.

Thanks
Russ

http://www.wossnerpistons.com/products/ ... okietest=1

Looks like the pin is 18mm and the compression height is 33mm so you'll need a longer rod with the large small end diameter.

Tim

For the rod I would use a yamaha outboard rod 6H4 which is 116 long , 22mm crank pin and 18mm gudgeon pin.

The other option for your piston is a DT250 which is cheap and has oversizes to 71mm. Both the DT250 and YZ250's have 18mm gudgeon pins

Thanks for the replies ....ive decided to go with a wossner 72mm from AF , as the other options meant changing conrod and head

carlos fandango wrote:Thanks for the replies ....ive decided to go with a wossner 72mm from AF , as the other options meant changing conrod and head

I take it they've got 16mm pins?