I wasout riding in a 25-30 degree day and for the hell of it I shut off the carb heaters, machine ran alot better, throttle response was quick and motor pulled hard. Before it ran ok but seemed to misfire once in a while sled is a vmax 700. Any body elese play with the heater?

I wasout riding in a 25-30 degree day and for the hell of it I shut off the carb heaters, machine ran alot better, throttle response was quick and motor pulled hard. Before it ran ok but seemed to misfire once in a while sled is a vmax 700. Any body elese play with the heater?[/b]


Well if you think about it, On your car or truck you can buy a COLD air intake like a K&N Filter kit, this allows cooler air to enter the motor generating more power. The carb heater is only ment for extreme cold weather. On my srx and 700 v-max I only turn them on in the morning and by the first 10 miles ill shut them off. Warmer air into the motor will cause sputter and lesser H.P.

I hope this helps!!

George

these heated carbs seem like a good investment... to my knowledge they are not on there stock.... how much for 3 carbs?

these heated carbs seem like a good investment... to my knowledge they are not on there stock.... how much for 3 carbs?[/b]
They should be stock, mine where, its just a coolant line off the motor

Is there an on/off switch of some type?

Is there an on/off switch of some type?[/b]
Yes there is a small ball valve, looks like a fuel shut off, mine is on the pto side just above the carb

And this valve should stay closed at all times unless i want heat going to the carbs?

And this valve should stay closed at all times unless i want heat going to the carbs?[/b]
Any carbed Yamaha of recent that I've ever seen had the heated carbs on it from factory. If your riding in extremely low sub-zero temps you open them up and allow the coolant to keep the carbs warm. It helps to prevent icing in the carbs. When riding in warmer temps you definetly want to shut them off or do as posted above and leave them open for the first 10 minutes or so, then shut them. Cooler intake air temp=more horsepower for sure.

But if i want better milage i can turn them on, because we all know we get bad milage in our cars on cold days :p

But if i want better milage i can turn them on, because we all know we get bad milage in our cars on cold days :p[/b]
Ummmmm, I'm not so sure that is right. Vehicles that are fuel injected may actually use slightly more gas on colder days because the ECM adjusts your fuel curve accordingly to the air intake temperature. For a carbed vehicle your not using any more or less gas then your jetting allows. Carb settings don't change automatically...Well atleast a standard carb won't..I'm not sure about electronic carbs (not found on any sleds I know of).

Cold air is thinner than warm air and also contains less moisture than warm air...which means your engine is able to suck in more air in cooler weather, creating more horsepower. I'm pretty sure it is actually leaning your motor out, as your getting more air to the same amount of fuel.(leaner is meaner...to a extent)
On warm days the engine cannot suck in as much air because its thicker which causes the motor to burn slightly richer and also having to burn off more moisture at the same time.
I'm sure someone else can put this explination into words better than myself but thats the basic principal behind it.....
Other arguements on this subject that I've found are that engine oil is thicker and creates more drag on the motor in cooler weather, air drag is increased in cooler weather(both reducing your fuel milage)...I dunno I'm no scientist or physics major....just what I've read though.
:tongue:

on my sled i only turn on the valve in very cold temps. i have heard that if you run in warm temps with the coolant on you can get the carbs hot enough to boil the gas in them.

Ummmmm, I'm not so sure that is right. Vehicles that are fuel injected may actually use slightly more gas on colder days because the ECM adjusts your fuel curve accordingly to the air intake temperature. For a carbed vehicle your not using any more or less gas then your jetting allows. Carb settings don't change automatically...Well atleast a standard carb won't..I'm not sure about electronic carbs (not found on any sleds I know of).

Cold air is thinner than warm air and also contains less moisture than warm air...which means your engine is able to suck in more air in cooler weather, creating more horsepower. I'm pretty sure it is actually leaning your motor out, as your getting more air to the same amount of fuel.(leaner is meaner...to a extent)
On warm days the engine cannot suck in as much air because its thicker which causes the motor to burn slightly richer and also having to burn off more moisture at the same time.
I'm sure someone else can put this explination into words better than myself but thats the basic principal behind it.....
Other arguements on this subject that I've found are that engine oil is thicker and creates more drag on the motor in cooler weather, air drag is increased in cooler weather(both reducing your fuel milage)...I dunno I'm no scientist or physics major....just what I've read though.
:tongue:[/b]

Good job, ha ha, i have a fuel injected van that i drive, i notice less milage...your right about the carbs...yes, teh ecm does adjust the fuel curve..... i know more about diesel ecms then gas.

DO YOU KNOW IF THERE ARE HEATED CARBS ON CATS TO , LIKE THE 99S?

DO YOU KNOW IF THERE ARE HEATED CARBS ON CATS TO , LIKE THE 99S?[/b]
I'm not really sure if any Cats had heated carbs on them, possibly the mountain sleds do...I grew up riding Yamaha's, thats how I knew they had them....my uncle has had 4 or 5 diffrent Yamaha's and they all had heated carbs with the exception of his 79 Yammie....

hahahahha that thing was a BEAST (the 79). Single carb pointing straight off the back of the motor right at your chest w/ a cheesy plastic door in between yourself and the carb barrel. Man when that sled would backfire it felt like you just shot a shotgun off. Could feel the shockwave in your chest. LOL
Of course...that sled had some carb issues....to make it run you had to choke it off for a second and crack the gas. So I used to ride with the plastic door open at all times....soon as she started to bog I would stick my hand over the carb barrel, crack the gas and take my hand off....she would do one of two things, either Wake up and scream or backfire...shooting a good 3-4 inch flame straight at my chest. :lmao:
It's amazing I still got into snowmobiling with that being the first sled I ever rode and all.....would think that shoulda been enough to scare me away from the sport.

Red, its because your a die hard snowmobiler.... like most of us. be proud! SWRules

I have had some old ones too , had a sled that would thow the belt at ya and it hurt but I would put on a new one and off I would go!