The FZR and FZS (SHO, 2009 to 2016, 1812 cc supercharged) have a clutch on the supercharger, and in forums it is the part that comes up whenever power goes missing. The early SHO engines from 2009 to 2013 had clutch problems that were revised later. What follows is an account of what owners describe, and of how much of it an app can confirm.
The pattern owners describe
The typical report is a ski that runs smoothly and starts normally, yet on the water it hangs around 5000 to 5500 rpm and does not come out of it. Power also falls away above roughly 6000 rpm. The intake pressure stays close to ambient pressure where you would expect it to rise with the throttle, which is the sign that the supercharger is not doing its job. This comes from several sources, so it is a recognised pattern and not a one-off.
One side note matters in practice: testing the clutch by hand is described as unreliable. A clutch that feels fine when turned can still slip under load. That makes the symptom and the measured pressure more useful than a quick hands-on check.
What the app can show
The M-JET Diagnostic shows intake pressure and barometric pressure in the live data, next to rpm and the throttle values. Three comparisons are worth making, and they do different jobs.
With the key on and the engine off, the intake pressure should sit close to the barometric value. If it doesn't, suspect the sensor itself (code 29 in the generation B list) before anything in the supercharger.
On a ride, log intake pressure against rpm and throttle position. If the throttle is wide open and the pressure stays near ambient while rpm sits at 5000 to 5500, you have recorded what the owner reports describe.
In the same log, keep an eye on engine temperature and intake air temperature (code 23). A ski that reduces power because of heat can look similar, and the log lets you rule that out.
What the scan cannot prove
A low intake pressure fits a slipping clutch, and it fits other things as well, including a leak in the intake path. The app cannot see inside the supercharger. It cannot prove clutch wear or measure the condition of the supercharger itself. What the data does is narrow the question and give you something concrete to show a mechanic. The same goes for the impeller: wear on it, a wear ring problem or debris in the intake are invisible to a scan.
Think of the log as evidence for the symptom. The next step is mechanical.
Hours matter on a used boat
When you look at a used FZR or FZS, the hours spread across rpm bands tell you more than the dash meter, which owners say is not always reliable. The control unit stores hours per rpm range, and a boat that spent a large share of its life in the top band deserves a closer look at the supercharger. The page about reading the operating hours explains how.
A sensible order
Read the fault memory and note the entries. Compare intake pressure with barometric pressure, key on, engine off. Log a ride and set pressure, rpm, throttle and temperatures side by side. If the data matches the owner pattern, take the log to someone who can inspect the supercharger and its clutch mechanically.
The app supports the FZR and FZS as well as the later supercharged FX SVHO models. The FZR and FZS boost page has more on the pressure values.
