Which carbs do i have?

[sergeantmay]

Im trying to find out which carbs are on my seadoo xp, Its got the rotax 657x engine.. Stock are the duel mikuni bn 38 which im sure thay are but i need to order some parts for them so i need to be sure which ones thay are, Ive measured the port where the main butterfly is and it measures a tiny bit over 38mm, Is this a way of teling what size thay are? All the carbs have on them is mikuni

 

[Dr Honda]

If they are bolted onto the stock manifold, and have a square pump body on it... they are SBN 38's. Even if they are a 40... it's irrelevant since they use the same parts.