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I don't have a wide band setup. What jet sizes and adjustments are people usin?g to get a 12.7:1 air to fuel ratio?
 

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Well... it's doesn't seem to work like that. :)

Craig from Rutting Rhino has done some extensive testing on how to dial in your setup for your location using some simple techniques and some jets. You can't just throw a new jet (or two) into your carb, adjust the A/F screw, and say 'This is 12.7:1 ratio!'. You need to trial and error your setup in your area (elevation).

Oh and you don't want 12.7-1 at WOT - more like 13.1-1 or 13.2-1. :)
 

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LOL

ummmm well were gonna need sum info from u sir to be able to tell u anything,

what elevation are you at what mods are done to motor intake what filter what exhaust what clutch weights what cdi 2 seater 4 seater what size tires,

all that plays into ur a/f every single bike is different

go buy a $175 a/f gauge on ebay and play away and u tell us what ur a/f ratio is , thx , lol- btw u da man
 

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I agree with all of the above comments...

Will say this about that...jet the carb for max acceleration from a stop is the short answer...

Some refer to wot as running at top speed but when I say wot I am referring simply to having the the throttle wide open...and the correct jetting will yield max power under max load which is max acceleration...which translates into getting from point A to point B in the least amount of time...most people will find that their a/f gauge reads around 13.5:1 wot under max load...max load is when the vehicle is accelerating as hard as possible...

If you don't mind paying for a gauge and installing it it is a great thing to have...

Don't worry about the numbers now...get the gauge...install it...then go to the next step of using it to help you squeeze every drop of power out of it...

The biggest mistake people make when using a gauge, however is fixating on the gauge and not measuring power with accuracy...

The simple method that gets it done is to let the stopwatch pick your jets...simply time your 0-300' runs for every jet size and use the ones that produce the lowest e/t's...if you have a gauge all the better...and always inspect your spark plug too...

Seat of pants dyno, a/f gauge, speedo can all lie/mislead you...

The stop watch and spark plug NEVER LIE...it does take a little practice to get good at timing your runs but we are talking a few minutes...don't assume your first attempt is accurate... :biggrin:

This is something I recommend everyone do before they ever start changing parts/tuning etc...

When your times repeat 2 out of 3 within a +/- .015 seconds of each other you can believe the two...if the third run is barely outside that window all the better...if not ignore the one that is far off the other two...

BTW... the 12.7 you made reference to is probably what you heard should be 14.7... that is not what you tune for...that is maximum efficiency...and with the stock carb on a rhino when correctly jetted for max power at wot you will find that your low throttle settings (cruising ) a/f is in the 14s and in the GOOD range for fuel efficiency...

Bottom line...the a/f gauge is a GREAT asset...but simply fixating on a gauge reading is not best method for getting best results...One thing it will tell you quickly once you have it installed and learn how to use it is what your current condition is relative to where you know it runs best when the elevation/temperature changes...and it can help you more quickly diagnose run-ability problems...
 
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