Yamaha fx cruiser svho 2017 - which Riva tune stage for stock engine?

[Impulses]

One question ... are the Riva Racing tunes the same as the Maptuner tunes ?

https://www.maptunerusa.com/tuning-l...svho-2014-2020

https://rivaracing.com/i-24083864-fx...-plus-kit.html

I ask this question because I see that Riva advertises satge 1 plus with rpm limit at 8.000 rpm requiring to modify prop, air filter and more ... ...on the other hand Maptuner advertises 8.300 rpm without changing any part of the jetski.
I don't understand...

[K447]

One question ... are the Riva Racing tunes the same as the Maptuner tunes ?

https://www.maptunerusa.com/tuning-l...svho-2014-2020

https://rivaracing.com/i-24083864-fx...-plus-kit.html

I ask this question because I see that Riva advertises stage 1 plus with rpm limit at 8.000 rpm requiring to modify prop, air filter and more ...

...on the other hand Maptuner advertises 8.300 rpm without changing any part of the jetski.
I don't understand...

I suspect you are confusing required/recommend hardware upgrades for the Stage 1 Plus tune with the RPM limiter included in each tune version.

The Yamaha ECU logs RPM in bands. The stock Yamaha ECU tune limits RPM below 8000. To conform to this (and avoid logging engine time above 8000) there are MaptunerX tunes that electronically limit engine RPM to right around 8000.

The ‘normal’ MaptunerX tunes have their RPM limiter set somewhere above 8000, 8300 for some, 8500 for others.

The Plus versions of Stage 1 Riva tunes expect that the engine air intake has been upgraded. Typically ‘cold air’ intake and/or the IMUK (which removes of the factory flame arrestor ‘ribbon’ disc from the intake manifold). These modifications increase the maximum amount of air flow into the engine cylinders so the Plus tune has corresponding increases in fuel delivery. The result is increased engine power and increased maximum RPM possible. Increased compared to the Stage 1 tune, and of course compared to the stock ECU tune.

The actual mechanical peak engine RPM on the water is determined by the match of impeller to engine power. More power will allow the engine to twist the impeller more strongly and increase the RPM that the impeller (and therefore the engine) turns.

As long as the electronic RPM limit is somewhere above the RPM that the impeller allows, the tuned engine delivers all the power it can into the impeller, and you achieve maximum speed (for that tune on that ski).

If the added engine power is enough that it could spin the impeller RPM higher than the tune allows, the ECU will electronically limit engine power to hold the engine RPM at or a little below the electronic limit. In this scenario the engine power is being reduced from the maximum possible, and the top speed is therefore also reduced.

The same applies to the Stage 1 tune when installed on a completely unmodified engine. No air intake changes, just a stock engine with the ECU tune changed.

If somehow the Stage 1 tune (with the stock impeller) could overrun the RPM limit set in the tune then the engine power will be reduced to hold the actual RPM to the electronic limit.

If you want to increase engine power but do not want the engine to turn more than 8000 RPM then the impeller may need to be changed. Changing the impeller to absorb more engine power near 8000 (for example) can ‘load’ the engine enough that the wide open RPM is a hair under 8000. You still go fairly fast, and the electronic limiter in the tune is not restricting engine power.

So, you first decide which RPM maximum you wish the engine to turn.
You select which engine hardware upgrades you will install, if any.
You choose the tune that matches the engine upgrades.
If that results in engine RPM that exceeds the target RPM, then the impeller must be changed*

* There are some other methods to absorb engine power and reduce the peak RPM, separate from changing the impeller.
One option is to install a Lucky13 tail cone inside the jet pump.

‘Changing the impeller’ can be done by physically altering the stock impeller, increasing the blade angle along the trailer edge of each blade.

The more common approach is to replace the stock impeller with an impeller selected to match the engine power and deliver the desired peak RPM at wide open.

[Impulses]

Thank you very much for your answer K447, so the Riva and Maptuner tunes are the same?

[K447]

… so the Riva and Maptuner tunes are the same?

The MaptunerUSA.com web page has the Riva branding, so it would appear that it is all Riva.



I often refer to the MaptunerX product sold by Greenhulk store and also sold directly by Riva as the Riva MaptunerX to distinguish it from the MAPTUN and Vtechtuned products, which also use the MaptunerX hardware unit.

[Green Hulk]

Thank you very much for your answer K447, so the Riva and Maptuner tunes are the same?

They are the same!
Maptuner/Riva MaptunerX products and tuning licenses are offered right here in the GreenHulk store at discounted prices
https://www.4-tecperformance.com/ind...ndex&cPath=271