View Full Version : Yamaha 2 stroke 40Hp 97 upgrade

11-16-2009, 04:25 PM
"Hey have a 40hp 2stroke -97, know it's the same engine 50hp, has now been and gone through, section by section and compared to 40/50 and I find nothing different. Carburetors are the same, exhaust, reed valve, etc., etc.. Have read that some have asked the same question, but feels that the answers do not correctly, because I been through some of the part is now on a spare page. So anybody out there who know what really distinguishes these engines? Grateful for answers / / Johan / / Sweden"

11-20-2009, 04:31 AM

carbs jets

12-10-2009, 03:58 AM
I thought exhaust housing and jets?