These are exactly the links that I was looking at last night, as I was thinking that I may have the wrong bearings... but I was not able to find the dimensions for the 2 different numbers listed, and I never thought to look at the engine label. However I did plan on calling SBT today to see if they would be able to measure the bearings listed or if they had more information on them.
Thanks Racerxxx I will check it out tonight when I get home, do you know off hand or from experience if the 657x/720 bearings are bigger?
I can't find any dimensions online so I can only go off what I located on SBT's site. I also found another funny thing that I totally skipped over on SBT site.
It just goes to show you really, really need to read things carefully as listed below:
NOTE: For 657x applications using OEM rods, you need 25-105 Wrist Pin Bearings.
http://www.shopsbt.com/seadoo-jet-ski-cylinder-exchange/62-104.html
Now, go and look at the SBT reman crank shaft---it fits both the 657 AND the 657X---and doesn't call out the need for a different crank for either application. Hmmmm, so if you think about it, they must swap to a standard 657 rod and junk the X rod. Those dirty bastards. I understand from their stand point, but once you start swapping stuff like that you burn the guy down the road doing a rebuild that is hot to trot and orders what he thinks is the correct part and gets the wrong part. It is nice that they supply the first guy the correct parts.
http://www.shopsbt.com/seadoo-jetski-crankshafts/20-103.html
As far as my experience with the 657/720 bearing difference--none, all deduced by research. All my stuff is 787's, but I remembered two versions of the 657 and it clicked in my head that I bet the rods are different. Also, if you ordered from SBT, THEY should have questioned you is it an X engine.