How many RPM should I on a 2005 RXT with stock SC and stock impeller?

[russellb]

My 2005 RXT is currently running about 60 mph or maybe slightly faster by the installed speedometer. My RPM has not reached 8000 RPM but is getting close. I have had the supercharger rebuilt and also had someone else double check the supercharger since I heard that there had been a bad run of lock nuts in the rebuild kits. I don't have any modifications. The only thing out of the ordinary is aftermarket ignition coils and aftermarket 42# injectors. Some people suggested that the 42# injectors may not idle properly but I have not had an idle problem. I still have my stock injectors and may have them professionally cleaned and reinstalled. Haven't replaced my fuel filter yet but it's definitely on the to do list in the near future. Any tips would be appreciated. I have an extra set of plugs so I may put those in and see what happens.

 

[red2blue]

My 2005 RXT is currently running about 60 mph or maybe slightly faster by the installed speedometer. My RPM has not reached 8000 RPM but is getting close. I have had the supercharger rebuilt and also had someone else double check the supercharger since I heard that there had been a bad run of lock nuts in the rebuild kits. I don't have any modifications. The only thing out of the ordinary is aftermarket ignition coils and aftermarket 42# injectors. Some people suggested that the 42# injectors may not idle properly but I have not had an idle problem. I still have my stock injectors and may have them professionally cleaned and reinstalled. Haven't replaced my fuel filter yet but it's definitely on the to do list in the near future. Any tips would be appreciated. I have an extra set of plugs so I may put those in and see what happens.

First things first....hard limiter on the '05's is 8150. W/ everything stock....cool weather...full fuel and a single rider...800'...fresh water...I was hitting the limiter...easy. And seeing 8100 is par. The warmer it gets...the less likely you are to hit the limiter...the heavier the load...same thing....salt water also affects the ski's performance...altitude...humidity...ect...ect.

Have you changed plugs at all since you've been experiencing this issue?

Absolutely no need for 42's w/o a bigger wheel.

You checked your prop...ring...pump...grate...opas?

 

[russellb]

I plan on blocking up the OPAS. Haven't done it yet. I bought the 42#'s because I could get a set for what one of the 38# injectors cost. I may try having the old ones cleaned but it will have to wait for after the holiday. I did some research on fuel injection systems and found that most systems can support up to a 20% larger injector. 42's are in the order of 10% and my ski is running much better than before. OPAS could be a problem because handling at lower speeds (around 25 mph) is awkward. Going to block it up because I pull kids on tubes often. I'm also a bigger guy so it might go a little faster with someone else or if I lose a few pounds. 60 mph is still a heck of a lot better than 45 that I was getting before. I have new plugs that will go in before I put it in the water again. I had no power on takeoff before with my clogged injectors. There is a world of difference now. I realize there is a possibility that it might actually run better with properly working stock injectors. If I still have the ski in 2 years when the supercharger is due a rebuild I will probably just go ahead and buy the X-charger and I'll already have the 42's.

 

[red2blue]

okay...dream-o-meter pretty much tells everyone they're hitting 70... the gps is telling them they're more like hitting 65-66.

I don't recall you saying...what kinda r's are you seeing @ wot?

 

[russellb]

I was probably around 7600 or 7700. I guess I was just too happy to at least be able to go 60.

 

[AircraftDoc]

How many hours?
Remove the jet impeller and clean up the leading edge. That will help.
After I cleaned up my impeller I topped out at 64-66 on smooth water. All stock.
If everything is running great, then a clean up of the leading edge will help.

 

[red2blue]

I was probably around 7600 or 7700. I guess I was just too happy to at least be able to go 60.

How do you check your oil level?

 

[russellb]

My impeller was sent out to a prop shop and reworked less than 10 hours ago. It had some damage and was out of balance.

How many hours?
Remove the jet impeller and clean up the leading edge. That will help.
After I cleaned up my impeller I topped out at 64-66 on smooth water. All stock.
If everything is running great, then a clean up of the leading edge will help.

 

[russellb]

My oil level is between the middle and the bottom of the dip. I actually drained about a pint when I was troubleshooting my problem.