View Full Version : calibrated speedos

07-12-2008, 10:13 PM
Hi. I was wondering why it seemed so much harder to complete the slalom course behind my boat than behind the Nautique at the ski school.

So, today I used a Garmin GPS watch to callibrate the speedometers which were off by 2 mph. When I was going 32 mph behind my Outback it was actually 34 and I'm not that good at the course. After calibrating, I suddenly became a much better skier.

The slalom wake is really impressive.


07-12-2008, 11:37 PM
Old school calibration, running a 13x13 prop (I think) was 3000 RPM = 30 mph and you can generally count on 3200 = 32 and 3400 = 34. Depends a bit on passengers and head/tail wind (on lake not river). So when both of your speedos take a snooze, make sure your driver knows those conversions.

What ski school did you go to? I bet they had Perfect Pass - which will also be a bit different pull than drive-by-hand, especially coming out of the turn .... And let's not forget the difference water temperature makes to how the pull 'feels'...

Glad to hear you are hitting your 32's. Is that long line or 15 off???


07-13-2008, 12:40 AM
I'm at 15' off. I was at the McGinnis ski school in Florida in April and this week I had a less at McClintock's which is about an hour's drive from my house in Toronto.

So far I'm using the Moomba Cruise, but am seriously considering getting PP StarGazer. Now that my 32mph is a real 32mph, I've noted that the wake and feel on my boat absolutely matches the Natique. As you can see, my skiing is not sensitive enough to tell the difference between Moomba Cruise and PP.

If I get PP, it's mostly so my driver (wife and father). Can take me at a consistent speed.


07-13-2008, 08:06 PM
I don't know about the star gazer version of PP but there is a big difference from Moomba cruise and PP wakeboard pro which i have. Star gazer was not available when i got mine.
Moomba cruise works OK for wakeboarding with beginners and such which don;t pull too hard on boat but for skiing particularilly slalom, it is way too inconsistant as it works on rpm's and they can be way off when skiing.I fully recommend the switch but follow what a few others have to say especially ones with stargazer as I think that is the way to go .

07-13-2008, 10:29 PM
After doing some research, I would suggest looking at Zero Off. It is totally GPS based and much easier to use than PP. The only set back, for me, is the cost and where I can mount it in an 08 OB. I only have 1 speedo, since your boat has 2 it would be easy.

CC already is exclusive to ZO and MC will be next year. So it has backing and waiting may help the price come down some.

07-13-2008, 10:34 PM
From what I can tell, Stargazer is available now for an 07 Outback, but there is no retrofit kit for Zero Off. Does anyone know any different?

07-13-2008, 11:28 PM
I'm curious? From what I have read, the GPS systems only works off of the GPS system and not the speedos. I boat on lakes and rivers that sometimes in the spring have a 5 or 6 mph current. With GPS only wouldn't my actual boat speed be off by the speed of the current?


07-13-2008, 11:42 PM
You are correct Mobi. If you are stopped in the river the GPS will read the river current. A good GPS computer could take that speed and direction and offset but it will be off as you get away from the main current. I sent an email to Zero Off a long time ago asking how they compensate for river current but they never responded. Sounds like the Snake and Columbia all year round..lol.

07-14-2008, 10:11 AM
Does anyone know, has anyone actually installed ZO of a 2007 or later Moomba?

07-16-2008, 11:25 PM
LAZ I don't think any one has put or can put a zero off in the Moomba right now, but Tazz just put a Star Gazer in. Seems like it went well but we are still waiting for him to finish his field test. Myself I have the PP Wakeboard pro and after working the set up bugs out have been very happy with it, and more importantly so has my wife the driver.

07-17-2008, 12:06 AM
I've decided to go with Star Gazer and will order it tomorrow. I'll let the group know how it works out.