# Yamaha Rhino hard starting



## gcs (Dec 1, 2011)

I have a 660 Rhino 4x4 that is very cold natured. I was wondering if anybody is having the same problem as I'm having with cold starts? My Rhino is a 2004 model. It has always been hard to start cold. Is there a fix for it and if so what? Any info. will be greatly appreciated. Thanks, Greg


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## muddychick01 (Dec 2, 2011)

My hubby has an 07 450 does the same thing. Haven't found a fix for it. Just treat it like an old carborated car. Turn the key on, pull the choke, pump the gas pedal 3 times and hope for the best. Oh yeah, and let it warm up for a few mins when you do get it started before you take off.


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## gcs (Dec 2, 2011)

I think that Yamaha went to fuel injection because they couldn't figure out the carburetor either. I was hoping that someone on here would have figured out what needs to be done. Idk if rejetting the carburetor would help or maybe getting a starter that would turn the motor faster while cranking.


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## Backlasher82 (Dec 2, 2011)

Well, first off it doesn't have an accelerator pump so stomping on the gas pedal is a waste of time, that will not help at all.

Second, it doesn't have a choke it has an enrichener circuit. The difference is, a choke is basically a flap to cut off the air through the carb. The enrichener opens a circuit in the carb that allows more fuel through but it doesn't restrict the air flow. So if you open the throttle at all while you're trying to crank it with the enrichener on, you allow air in which defeats the purpose. They call it a choke because most people know what a choke is but might not understand the term enrichener. Bottom line is, pull the "choke" full on, don't touch the throttle and it will start faster when cold.

Third, most likely your cold starting problems could be helped by having the mixture screw adjusted. All of the carbed motorcycles, ATVs, etc are shipped with the mixture screw adjusted too lean from the factory. Fuel still comes through the pilot circuit when the "choke" is on, when the "choke" is off the only fuel is coming through the pilot circuit. There is a fixed pilot jet that allows the fuel to come out of the float bowl but the mixture screw restricts the amount of fuel that actually goes into the carb venturi. Bottom line on this one is, if you have an ATV mechanic worth a flip it's no big deal for him to adjust your carb. 

Some carbs have a brass plug pressed into the carb covering the mixture screw that has to be removed but it's very simple for someone who knows what they're doing. Someone who doesn't know what they're doing can ruin a carb by driving the mixture screw into the carb while drilling out the plug.


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## gcs (Dec 3, 2011)

Thanks Backlasher for the info. I'm going to take it to a motorcycle mechanic after deer season. I've taken to have it serviced and had them to check the hard starting problem out before but it was in the summer time. I'm going to do it this winter while it's cold out and maybe they can see a little better how hard it is to start in the cold. Thanks again, Greg


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