Riva spacers?

[Pinhacker71]

Late last season I did the ribbon delete and removed snorkels. Didn’t really notice any increase in rpms. I max out at about 7500. Changed plugs beginning of this season and still at 7500. I just removed the ribbons and rubber sleeve but didn’t place the Riva spacers. I’m going to place the spacers to see if it adds rpms. Am I just wasting my money? Anyone tried it both ways yet? Which spacers should I order. Seems like there are a couple of different ones. Thanks for any feedback. Max speed 46. No fabric on Bimini, 1/2 tank gas. 5 people, not large. Calm water.

 

[haknslash]

This is the sleeve I used on my 192 (SHO) https://rivaracing.com/i-14305221-riva-yamaha-svho-sho-ho-intake-manifold-upgrade-kit.html. It works for HO (Naturally aspirated 1.8L), SHO and SVHO engines. For me the biggest thing I noticed was an increase in throttle response. My top speed wasn't affected but I did gain maybe 50-100 RPMs. Personally I don't think you'll see a big difference compared to what you've already done. Many on here don't even use the sleeves. I just splurged when I bought mine and figured why not have a smooth path for the air to go instance of the ridges left from where the ribbon and rubber gasket would have been.

Not sure if E-series does any kind of different electro-gizmo crap than a non-E series that could be holding you back.

 

[scokill]

Late last season I did the ribbon delete and removed snorkels. Didn’t really notice any increase in rpms. I max out at about 7500. Changed plugs beginning of this season and still at 7500. I just removed the ribbons and rubber sleeve but didn’t place the Riva spacers. I’m going to place the spacers to see if it adds rpms. Am I just wasting my money? Anyone tried it both ways yet? Which spacers should I order. Seems like there are a couple of different ones. Thanks for any feedback. Max speed 46. No fabric on Bimini, 1/2 tank gas. 5 people, not large. Calm water.

I think you answered your own question....the first one. The second and third one shouldn't need an answer.

 

[Ronnie]

Just be sure to remove the rubber sleeve if you go remove the ribbons, another member left the rubber sleeve in when he took the ribbon out a season or so ago. The sleeve end up getting sucked into the engine where it came apart and destroyed the engine. Not an inexpensive or easily fixed problem at all for a mod that costs next to nothing and gives me very little, if any performance gain at sea-level imho.

 

[swatski]

Late last season I did the ribbon delete and removed snorkels. Didn’t really notice any increase in rpms. I max out at about 7500. Changed plugs beginning of this season and still at 7500. I just removed the ribbons and rubber sleeve but didn’t place the Riva spacers. I’m going to place the spacers to see if it adds rpms. Am I just wasting my money? Anyone tried it both ways yet? Which spacers should I order. Seems like there are a couple of different ones. Thanks for any feedback. Max speed 46. No fabric on Bimini, 1/2 tank gas. 5 people, not large. Calm water.

That is strange. Most people report ~200RPM gain in N/A 1.8s, as long as the engines are running under the rev limiter (~7,800RPM) before. This mod does not work in 230 MR-1s but works very well in 1.8s (N/A).

Something else is limiting. I would be surprised if it is the spacer, but those are easy to install and not super expensive.
Maybe air filters? (doubt it)
Is your boat a CARB (4 star) model by any chance?
46mph is okay but you should be closer to 50 I would think, as long as the elevation is low.

There are two different sizes of ribbons (and therefore spacers). Yamaha has changed the intake manifold back and forth and you will need the the exact model information to make sure you buy the correct size. It doesn't matter if it is boat or ski, but there is a larger and a smaller ribbon/choker.

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[SamCF]

For sure not worth putting the spacer in if you have already done the delete. Way to much work for most likely no gain.

 

[Neutron]

Some will argue that the air doesnt have a smooth transition and is turbulant.
Dont know of anyone trying it without the spacer, then with on there boat.

If it runs good. Leave well enough alone

 

[Pinhacker71]

Runs great. Would like the extra rpms though.