Heated carbs on the RX?

[Turbo50Mike]

So, Impala, are you replying to your own reply?



MJB

 

[impalapower]

Easy now turbo. I forgot, do you get better milage in warm or cold weather?

 

[Turbo50Mike]

Depends how the carbs are jetted. Since the assumed conditions would be below freezing for the snowmobile, you would most likely get worse mileage in the summer (warmer) conditions than in the colder since the mixture would be slightly rich.

The heated carbs may be there for a reason to keep the intake temps at a somewhat consistent temp - Shutting them off and running the sleds in -0 temps may run it too lean if you were racing across the lake for a mile and may end up with some melting pistons. Maybe....

MJB

 

[impalapower]

Heck with milage, I need my reliability, I'll leave them alone. Heated carbs they are.

 

[Turbo50Mike]

When is Yamaha going to get with the program and get some fuel injection on their sleds so we can run at any alt, and any temp without worry?

MJB

 

[impalapower]

Didn't they have something five or so years ago that oxengated the fuel, simialiar to Ski-don'ts setup? Don't they still use it? I'm not into the mountain sleds.

 

[Turbo50Mike]

Well, in these parts, (NorthEast) most gasoline companies are required to oxygenate their fuels from November to April to help reduce emissions.

MJB

 

[impalapower]

I guess you will have to check the dealers. Yamaha never went fuel injection, maybe never will. Ski-don't did it for only one year and that was about 10 years ago. Don't think Polaris does anymore. Cat still did recently and probably still does.

 

[tmk50]

Didn't they have something five or so years ago that oxengated the fuel, simialiar to Ski-don'ts setup? Don't they still use it? I'm not into the mountain sleds.

On some of the 96 and 97 600cc twins Yamaha had what they called Smart Carbs. Basically what Ski Doo calls their DPM these days. Not sure why Yamaha dropped it. There was a switch that you could flip back and forth for oxygenated fuels.

 

[impalapower]

tmk50, I remember that, I heard it was the leader in the industry. Who knows why they dropped it. Get something right, then dump it.

 

[JDKRXW]

When is Yamaha going to get with the program and get some fuel injection on their sleds

I don't think you're going to see F.I. very soon.
1) It's too expensive
2) You don't get the same benefit that you do on a two stroke (4 stroke performance doesn't go to crap the way a two stroke's does with changes in temp and altitude)
3) I believe that the carbed RX motors pass the emmisions tests all the way to 2010
4) see #1

Heated carb bodies don't warm the intake air. The bodies are warmed in the areas where ice could build up to stop this from happening (to make sure condensed h2o vapour gets sucked into the engine).
This is not the same as, say, a carburated airplane engine where hot air gets dumped into the carb. inlet (you loose performance instantly when you turn on the carb heat.... but it beats the alternative)

 

[Turbo50Mike]

Heated carb bodies don't warm the intake air. The bodies are warmed in the areas where ice could build up to stop this from happening (to make sure condensed h2o vapour gets sucked into the engine).

I don't know. My R6 (It's a motorcycle - see avatar)also has heated carbs and you won't find me out there riding when temps are below freezing, that's what leads me to believe it's for consistent intake temps as well as preventing icing on the sleds. Maybe it's just to warm the fuel to a consistent temp, but there's got to be a reason for it.

MJB

 

[race24x]

Where are you from Turbo Mike I am from Maine I ride a Hayabusa you mentioned northeast. I think FI is closer than you think the bikes are getting it already and the sleds are soon to follow. I think they are just holding back som estuff and releasing it to keep the line alive for a few years get the most they can out of the same model. This year 4 stroke next couple better suspension and seat a couple more years FI then who knows maybe a hover craft RX1 LMAO

 

[Turbo50Mike]

I am from New Jersey - in the North East corner.

Like you said, maybe the second generation of the RX1 will have FI, maybe they'll even put in the new 180hp R1 motor!

MJB

 

[JDKRXW]

but there's got to be a reason for it.
MJB

Even on a bike, carbs are heated for icing. Believe it or not, carburetor ice WILL form at outside air temps. of up to 70 degrees F if the humidity is right (when flying a carburated plane, you MUST be prepared for carb ice whenever the dewpoint and outside air temp are within 3 degrees of each other).
This inlet air temp. drop is exactly opposite to what happens to the air when compressed by your turbos. The turbo heats the air when compressing it, and when put under vacuum, the air temp drops as it travels through a carburetor.... and adding vapourized fuel lowers the air temp even further.