Like many of you, as the temperatures get colder ideas start to flow for the winter build season. I recently started working at a jet ski shop one day a week for trade on parts and machine work. With the arrangement I have set up I have some options on parts and machine work/porting that will cost me nothing out of pocket, just time pulling engines and sweeping at his shop.
Currently my ski is a 91 SN with a 62t/62t @150, 62t ebox, sbn 38s, Coffman sizzler, Coffman silencer, worx 201, concord big hub 9/15. I recently transitioned from the 61x cylinder @170 to a 62t due to a failure and I like it more with this props pitch, even though it has less compression due to the head it seems Im more in the meat of the power with this prop/cylinder combo. It is used as a rec ski, no flat water flips in my future are planned, some boat chasing and nose stabs and general screwing around is about all I do. Top speed is 41mph currently and I could go for a few more mph, pipe tuning will get me there I am sure.
Over the winter I plan to at a minimum port whatever cylinder I use as well as a set of 760 cases. Additionally I will be installing a programmable zeeltronic ignition with some 760 electronics I have.
The shop I am working at has a graveyard of yamaha, kawi, and seadoo/polaris skis. What parts can I use off of these skis that will be an improvement? I know he has a few blown 1200 non PV motors, can the carbs be used off of them or are they a different bolt pattern? How about the sleeves? He has a 760 cylinder that I am debating, I think I can get away with it with my extremely low pitch prop and lots of timing in the ignition.
The owner values these used parts pretty low so I could likely end up with a lot of of them if there are any diamonds in the rough worth grabbing.
To recap. I think I want to roll with the 62t or 64x cylinder due to my prop/riding style, I will be porting the cylinder (super stock/FS) and cases, I would like to use larger carbs if I can salvage them off of one of these dead skis. I would like to continue running pump gas with little to no worry of WOT runs.
Optionally I could mill 1 or 2mm off the base of the 760 cylinder to lower timing and cut 1 or 2mm of relief in the domes, let them stick out the bore a bit.
If anyone wants to help me plan this out I would be grateful. I think my logic is sound but I welcome you to shoot holes in it or suggest alternative build options. Thanks in advance.
Currently my ski is a 91 SN with a 62t/62t @150, 62t ebox, sbn 38s, Coffman sizzler, Coffman silencer, worx 201, concord big hub 9/15. I recently transitioned from the 61x cylinder @170 to a 62t due to a failure and I like it more with this props pitch, even though it has less compression due to the head it seems Im more in the meat of the power with this prop/cylinder combo. It is used as a rec ski, no flat water flips in my future are planned, some boat chasing and nose stabs and general screwing around is about all I do. Top speed is 41mph currently and I could go for a few more mph, pipe tuning will get me there I am sure.
Over the winter I plan to at a minimum port whatever cylinder I use as well as a set of 760 cases. Additionally I will be installing a programmable zeeltronic ignition with some 760 electronics I have.
The shop I am working at has a graveyard of yamaha, kawi, and seadoo/polaris skis. What parts can I use off of these skis that will be an improvement? I know he has a few blown 1200 non PV motors, can the carbs be used off of them or are they a different bolt pattern? How about the sleeves? He has a 760 cylinder that I am debating, I think I can get away with it with my extremely low pitch prop and lots of timing in the ignition.
The owner values these used parts pretty low so I could likely end up with a lot of of them if there are any diamonds in the rough worth grabbing.
To recap. I think I want to roll with the 62t or 64x cylinder due to my prop/riding style, I will be porting the cylinder (super stock/FS) and cases, I would like to use larger carbs if I can salvage them off of one of these dead skis. I would like to continue running pump gas with little to no worry of WOT runs.
Optionally I could mill 1 or 2mm off the base of the 760 cylinder to lower timing and cut 1 or 2mm of relief in the domes, let them stick out the bore a bit.
If anyone wants to help me plan this out I would be grateful. I think my logic is sound but I welcome you to shoot holes in it or suggest alternative build options. Thanks in advance.
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