03-23-2008, 03:54 PM #1
What could be causing slow speed?
I went riding today for the first time since sept.
07 gpr milled head by jim, 1200 grate, ppk, 14/20, box stock R&D plate, airbox mods, d-plate, blue ff, jetworks, efi set 4417. air temp 46 water temp 40.
Top speed 66.2?? wtf
one thing that i did notice although i dont think i can attribute to slow speed was the tube for cooling passage #3 on the head popped off. when i pulled the seat the hull was full of water and there was exhaust smoke.
would that alone cause such a slow speed? anything else i could be missing?
also on takeoff ski cavitated a little. thanks
03-23-2008, 03:58 PM #2
oh yeah and i weigh 196 and rpms were 7150 (commercial tiny tach)
i think when the hose popped off the rpms were shooting up to 10000 on the tach and the ski was sputtering up top.
03-23-2008, 05:40 PM #3
Has your tunnel been reinforced? A cracked/leaking tunned will cost you about 5mph
Edit - Just checked that your only top speed mods are the prop and rideplate. The FF, D-plate, and 1200 could probably negate any top speed gains...
03-23-2008, 07:12 PM #4
i have milled head and efi as well as f/a
03-23-2008, 07:19 PM #5
You have #3 dumping into you hull and you are loosing speed?
03-23-2008, 07:21 PM #6
How much water in the hull? Did you fix the leak and go run the ski hard? Water ingestion is no good.What speed/rpm did it normaly run? PV's opening?
Last edited by WATER WOODY; 03-23-2008 at 07:28 PM.
03-23-2008, 07:47 PM #7
If there was exhaust smoke inside the hull you lost your FF or something. Just the smoke alone will kill your speed. Need to tear everything apart and inspect.
03-23-2008, 08:50 PM #8
by the time i realized there was water/smoke/#3 hose off i was idling back to the trailor. Im going to tear it apart and try again next week
03-23-2008, 08:52 PM #9
and in addition I have no baseline. Last year my ski was completely stock except for dplate and grate. This was my first time out after all the mods
03-24-2008, 05:15 AM #10
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