Help With Barrel Rolls

brapperdoodle

brapperdoodle

Location
Asheville, NC
LPW 735cc Shredder, single 46 with WetJet intake, stock flame arrestor (cause they're the best at keeping water out of the engine) with just 1 screen. Zeel ignition with LPW curve, B-pipe MOD chamber, H2o waterbox. Nothing too fancy but a solid rec ski. Everything in the build was new and or OEM Yamaha. I cant remember the jetting but again, this was set up by Paul so I trust it. New SBN 46, not a used carb. Pressure tested engine and had absolutely 0 psi loss at 9psi for 8 minutes. compression is just under 200psi and even on both cylinders. New RRP "superjet" style tank, fuel system holds pressure for days. Ski starts perfect and promptly always, cold or hot, Idles perfectly.

This is the vid I sent to show the ski in action. Keep in mind, Im not aggressively riding the ski, this was just to show some low RPM to WOT hits and pulls.
 
S

Storbeck

Location
Minnesota
Don't forget the significance of nozzle size. Some 148's are built on 155 sized pump bodies and use 155 nozzles and some 148's are built to be 144 sized and use 144 nozzles. Fastfairlaine said he was using a one degree lower trailing edge with an 89mm nozzle vs a degree steeper with an 87.5mm nozzle which is a pretty significant difference although both sound not 100% certain on that number (and presumably some sort of best in the biz pump guy would be well aware of this).

If your trim is compatible with stock nozzles it's cheap and easy to have a few different size nozzles so you can quickly and easily swap and test higher or lower pump load. It's probably not the most optimal thing possible but better than not trying anything.
 
sjetrider

sjetrider

615 Freeriders are addicted to T1 madness.
Location
in the 615 (Nashville)
brapperdoodle said:
148, Supposedly the impeller is a 7/16 not sure on cutback. Thrust trim and nozzle, I believe that’s 86.5mm
I haven’t been motivated enough to pull my pump and deal with it. So many other projects always going on! I just knew something was off because when I rode Sanoman’s FX-1 with the 144, it hit WAY harder off bottom and we are running identical engines/carb and electronics. His ski isn’t so much lighter than mine that it would make that big a difference. Almost every ski I’ve ridden hits harder than mine. Don’t get me wrong, it rips but it doesn’t have that smack on the bottom that it should.
Click to expand...
Just one detail and not saying it cannot be done with thrust trim, but an X-Screem or other trim systems with the rubber coupler in them turn INSANELY faster that the Thrust so it may help.
 
You must log in or register to reply here.
Top Bottom