SN build

Picked this up Friday night. 650 Protec pipe and head. Pulled engine and found pump only rotates 90 before contact. Mid shaft bearing also locked. Engine spins/strong comp-but no gauge verification yet. 2 of the 4 main Pump bolts were wet. It has Protec ride plate, Protec intake grate, and I assume Protec impeller.

I enjoy surf riding and rec riding. Not looking for wild power.

*Goals -repair pump and mid first
-clean up engine bay
-rebuild engine

*Engine goals - mid range power (budget >$1.5k)

I am leaning toward finding 61x cases-and purchasing a JetManiac ported 701 topend kit. New reman crank will be needed. carb rebuild needed (44 Mikuni on the 650 should work with jet change?).

I also plan on reusing the 650 pipe with a 61x exhaust manifold.
D1582386-AEC1-4368-9661-50066DF96B8C.jpeg09D4681C-69F0-4556-834F-50415B788FC3.jpeg
 

be_lain

Currently sending it
Location
Oregon
Highly recommend the ported jetmaniac top end kit. Just built my 61x over winter and am super happy with it. Also did boyesen reeds and sbt crank. I think I was just over a grand with all that plus some other little things (gaskets, bendix, carb rebuild etc). Add in a head and you’ll be about the 1500 range.
 

be_lain

Currently sending it
Location
Oregon
I have a sbn46 but stock bored intake. Just aftermarket reed petals is all. Also if you order your top end from jetmaniac just tell him what you’re running and he provides jets and baseline settings for your setup. They are pretty dead nuts, I haven’t had to deviate from his tuning suggestions.
 
Hazard Pole went on super easy. I used a foot long 3/8” ratchet extension on the opposite side to guide the pole bolt through the spring/holes.
616AC91D-0F42-46D7-B5F1-9DDE78084B2C.jpeg
 
Snapped off the single bolt holding down the protec pipe. I didn’t use the proper isolator, so I had that coming..

Removing the chamber wasn’t too bad (to remove the head for bolt extraction). Thought I was going to have to pull the motor. Reassembly went pretty quick thanks to Jetmaniac having the protec isolators in stock and at my door in 2 days.E1DBEFF7-EF58-4321-86D3-465B5B0B6D86.jpeg4DD792CC-A8C4-4683-8094-4FD19F159B7A.jpegAE8E4BCB-C01F-4075-BFFF-14C49069D90E.jpeg
 
Snapped off the single bolt holding down the protec pipe. I didn’t use the proper isolator, so I had that coming..

Removing the chamber wasn’t too bad (to remove the head for bolt extraction). Thought I was going to have to pull the motor. Reassembly went pretty quick thanks to Jetmaniac having the protec isolators in stock and at my door in 2 days.View attachment 372778View attachment 372779View attachment 372780


JetManiac has been a savior on my SN build as well! So awesome to have a one stop shop like that!
 
Ok all: Im looking for more low-end power since I primarily ride on a large river with 1-2ft chop. I have more topend than I need since my speed is limited to what feels like 25mph.

My current mods are a protec pipe and a scat 12/17 prop.
 
Location
dfw
I would bore the nozzle and bend the prop a little flatter. This will make it come to life quicker and pull noticeably harder without touching the engine. Raising compression may make it more snappy but fuel quality and carb tuning will be more critical. Basically it will be easier to stick a piston at full speed.
 
Top Bottom