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Discussion Starter #1
I'm running a stock setup, carb, exhaust and filter.
I'd like to make sure I'm getting the most out of the fuel delivery system. I ride from 3000 to 5000 ft. and was wondering which main jet are in the stock machine and what number jet I should have for my elev. Is the stock needle adjustable-c-clip/notched needle?
 

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The stock needle is adjustable by swapping, adding/subtracting the small washers provided inside the slide/needle assy...

The "adjustment clips" on the aftermarket needle are a joke...and the stock needle works better...especially at higher elevations...it has the correct diameter and taper...adjusting it more than the range provided with washers is a bad thing...

Carb jetting/tuning is considered fuel metering...

Fuel delivery system is from the pick up tube in the tank all the way to the carb fuel inlet...

The key to good performance on the Rhino is a high flow air intake...the higher the elevation the more critical it is...making sure the carb gets gas all the time...having the correct pilot and main jets...the correct idle a/f screw setting, and the correct idle speed setting...

If all those things are done correctly with the stock needle in the stock position...there is no need to adjust the needle...but that should be considered fine tuning and done last...

We sell a complete fuel delivery system that works with the stock fuel pump...and a jet kit that will give most people everything they need...

Now for the simplest things you can do free...

First...the stock carb from the factory had a 40 pilot jet, and a 145 main jet (unless you have an 04 in which case it's a 150) ...the idle a/f screw is set at 2-1/8 turns out...

You should change that to 2-1/2 turns out...that will richen the idle a/f and help prevent lean popping on decel and downhills...

Set your idle speed to the lowest reliable rpms in gear with brake on when motor is fully warmed up...this will also help prevent lean popping on decel and downhills...

If you have an 05-07 the stock snorkel from the air scoop to the air box lid is highly restrictive and causes a lot of problems especially at high elevations....

The simple and easy way to get a lot more air in and less noise is to simply remove it...and seal off the hole in scoop...that should eliminate the need to change main jets...

If you do those things and you don't have fuel delivery problems you might not have to do anything else...

But if you do...we have what you need... :)
 

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i need 2 get a stock needle with the lil things on it , all i have is the dj needle and ive been wanting to try stock again ,
 

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The key to good performance on the Rhino is a high flow air intake...the higher the elevation the more critical it is.

If you have an 05-07 the stock snorkel from the air scoop to the air box lid is highly restrictive and causes a lot of problems especially at high elevations....

The simple and easy way to get a lot more air in and less noise is to simply remove it...and seal off the hole in scoop...that should eliminate the need to change main jets...
Agreed on the stock restrictive intake, but....

IF you still want to run the STOCK airbox w/lid...

Why remove the scoop and drill holes in the airbox?? Just modify the stock air bell to a RAIS tube(less than $20 at Home Depot, ) and be done with it. Stock appearance, TONS more air.

Search "RAIS Tube", a lot of info on it. Even have the part #'s for the needed items at HD.

Works great on my car.

FWIW. C-Ya!!
 

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Since you are asking me why not... (otherwise I wouldn't care...) :)

NOISE...the stock is too loud for me...opening up the i.d. of the snorkel is loud as hell....and that would be the only bad thing about it imo...

I didn't recommend drilling holes...but it is a good option for more air with the stock filter...and air box lid delete adapter for clamp on is also a good way to go if you want to stick with foam filter and have the option of running w/ or w/o a lid/snorkel and keep the airbox...

But there are a lot of ways to do an air intake...I have done most of them myself...including using a 3" i.d. adapter to the scoop... which is higher flow than the shop vac nozzle...and cost less...it's also more of a hassle to get engine cover on/off...

I prefer no airbox at all... max power and relatively low noise compared to air scoop in cab...and there a quite a few options there as well as all the degrees of modifying the stock air box...

My advice was based helping get a handle on the problem he's having and things that don't require any money or customizing...what kind of air intake is best is another topic...

As for jetting a stock carb... 660 Mikuni Jet Pack

Thanks for asking... :)
 

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Discussion Starter #8
RuttingRhino:
Is there a chart as to the correct size main jet for a particular elevation?
I remember when I purchased a dyno jet kit years back for the ol'Honda it had a chart. I'm just wondering whether it's worth my while to change the main jet from 145 and pilot from 40.
I ride water and mud so modifying the air box would mean a snorkel. Probably not going to do that though.
 

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Don't believe any chart...

Only you know whether or not you need an airbox but if you are in water over the floorboards that is deep enough to need one imo...

However...if you don't think you are in water deep enough to go into the opening in the airbox taking the stock snorkel off is going to help a lot...

The RAIS type is the next best thing for you imo...and if you are gonna snorkel for deep water that's a whole other ball game...

If you are in too deep of water to run 04 style then you probably too deep to keep water out of your cvt also....but that is for you to decide...

You do NOT need to put a smaller than 145 main jet in it for 5000'...that is not as big of a deal as you think...if you were at 1000' and can't run a high flow intake that might be different story...but again...more air in is the key to success...not a smaller jet...but if you are gonna go buy a smaller jet...get a 140... do not get a smaller pilot jet... adjust your idle a/f screw for richer or leave it stock setting...

You can lower your needle by removing the small washers also...that will lean it some if you are too rich...but I don't recommend it...more than likely it will lead to lean popping on decel and down hill...and you are probably better off raising it for richer on low end...but again...it's better to have a bigger pilot jet...

The bottom line is when it come to more air, adjusting the idle a/f...and tinkering with the needle position those are all 100% free and any time you make a change that hurts just go back the other way...

The thing to do imo is stay out of the water and buy my intake, fuel delivery and jet kit...you'll be golden... :)
 

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There is no chart to show you what to start with, but once you have it correct at a particular elevation and temp MIKUNI has a nice slide chart that shows you where to go with the jetting if the temp or elevation changes. If I recall correctly about 2000' or 20 degree was a jet size.
 

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There is no chart to show you what to start with, but once you have it correct at a particular elevation and temp MIKUNI has a nice slide chart that shows you where to go with the jetting if the temp or elevation changes. If I recall correctly about 2000' or 20 degree was a jet size.
I used to have one of those about 10 years ago for my 2 strokes.
 

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well,if i may add,i am located at 1500 feets,at idle my engine smell like if it is on choke a bit,,.
i also found that my carburator air screew is always plug,,,so i will unpluged her tomorrow.

should i raised 1 position my needle?

i will check if i have 2.5 turn on the air screew also
thanks all
Gef
 

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The stock needle is adjustable by swapping, adding/subtracting the small washers provided inside the slide/needle assy...

The "adjustment clips" on the aftermarket needle are a joke...and the stock needle works better...especially at higher elevations...it has the correct diameter and taper...adjusting it more than the range provided with washers is a bad thing...

Carb jetting/tuning is considered fuel metering...

Fuel delivery system is from the pick up tube in the tank all the way to the carb fuel inlet...

The key to good performance on the Rhino is a high flow air intake...the higher the elevation the more critical it is...making sure the carb gets gas all the time...having the correct pilot and main jets...the correct idle a/f screw setting, and the correct idle speed setting...

If all those things are done correctly with the stock needle in the stock position...there is no need to adjust the needle...but that should be considered fine tuning and done last...

We sell a complete fuel delivery system that works with the stock fuel pump...and a jet kit that will give most people everything they need...

Now for the simplest things you can do free...

First...the stock carb from the factory had a 40 pilot jet, and a 145 main jet (unless you have an 04 in which case it's a 150) ...the idle a/f screw is set at 2-1/8 turns out...

You should change that to 2-1/2 turns out...that will richen the idle a/f and help prevent lean popping on decel and downhills...

Set your idle speed to the lowest reliable rpms in gear with brake on when motor is fully warmed up...this will also help prevent lean popping on decel and downhills...

If you have an 05-07 the stock snorkel from the air scoop to the air box lid is highly restrictive and causes a lot of problems especially at high elevations....

The simple and easy way to get a lot more air in and less noise is to simply remove it...and seal off the hole in scoop...that should eliminate the need to change main jets...

If you do those things and you don't have fuel delivery problems you might not have to do anything else...

But if you do...we have what you need... :)
What high flow filter do you sell?
 

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What high flow filter do you sell?
well,since my last message in 2015 a lot has happened.
Finally i took my Rhino at a Certified Yamaha dealer and he told me that the 'inside' ,,jets,,were so
been worked by an 'suppose to be expert' he advised me to undo and rebuilt it OEM and that what i did and it shows a lot.
It is at cold weather that it is hard to start (-15 celcius) and i will check if there is current at the small heater element of the carb if it works but i am not sure,is it controled by the ECM of somewhere else??

also my choke is really hard to pull so i will order a new one from YAMAHA ,,no jobber.

also i need a kit to rebuilt the fuel pump and i suspect that the fuel line with time just get empty,,,
on my year of skidoo we used to have a one way valve so the fuel line would not discharge,,i wonder if there is one on my Rhino??

also the air filter is in foam,,i am thinking of buy a new one ,,its a 2006 !!!

thanks for your response and Best 2021 for you and your family
Ride safe

Gervais
Riviere-Bleue,Quebec near Estcourt,maine
 
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