2005 Yamaha Kodiak 450 Smoke

[fender13bender]

I got my 450 running again after it sat for a year. Fresh fuel, cleaned plug, ect.

A little bit of history, when I got it (brand new) it seemed to smoke a little bit. It smelled like gas so I figured it was rich. I don't know if this has anything to do with my problem or not.

Now I took it out and rode for 10 or so miles this weekend and it definitely isn't the wheeler it used to be. It is slower and doesn't run as well. Dies at idle usually and is harder to start.

And it is really smoking, not at all when I'm on the gas, but all the time when I let off the throttle and it's slowing down. I mean, I think the thing is burning oil like no tomorrow. Does anyone else think this is it?

I guess it's probably time for a rebuild. I don't even have 1000 miles on it yet. I would like to bore it and get a high compression piston and cam and such, but I would like some info on that too.

Any answers are great, thanks in advance!

Oh and I forgot, the heat indicator light has been coming on and off.

[yamaha468]

What color is the smoke, did you clean the carb, did you check the oil to make sure it doesn't smell like fuel?

[DirtDemon]

Yeah, after it has been sitting for that long, the carb is most likely going to need a good cleaning. It could also be that your float is sticking. The fact that you say that it only smokes when you aren't on the gas makes me think that you are just getting too much fuel at at low engine speeds. I would guess that the air passage to the idle curcuit is clogged. Yamaha468 brings up some other good points too. Check the oil and make sure it hasn't been diluted with gas, and the color of the smoke will tell you what is causing it. Black smoke=too much fuel. Blue smoke=burning oil. White smoke=burning coolant. As far as the heat indicator light goes, once again, it could be the carb. If the main jet is gunked up, then you will be running lean on the top end and that will cause the machine to run hot. I would definately clean the carb to start.

Edited October 27, 2009 by DirtDemon

[yamaha468]

Another thing. If the engine it way to rich, it can wash the cylinder out. In other words. If you are running so rich that the oil that coats the cylinder wall is being diluted too much, you could end up with worn piston rings or excessive cylinder bore wear. That's why I wanted to know smoke color. Just like DirtDemon said, color can help diagnose the problem. Another problem you could run into if your carb is dirty is the carb leaking fuel into the cylinder while the bike isn't running and causing the oil level to increase. If your oil level is too high, it will cause the motor to lose power due to the crank, rod, and piston having to move through excessive fluid. Anyone who has ever overfilled a 400ex can tell you that. Check your float to be sure there is no trash in the seat that would cause the float to stick. If your float sticks it could cause excessive smoking in low rpm.

[fender13bender]

Ok thanks for the response guys. I'm almost positive the smoke is blue. Like I said it's only when the fourwheeler is not on the throttle. I'm going to check what you guys suggested when I get home from work.

[fender13bender]

Blue smoke check, low oil, check, and when I drive it on the hard side, theres a clinking noise, like two wires touching and sparking. Looks like it's time for a rebuild. I need help though, never done a wheeler before. I'd like to bore it out and ect, get some decent gains. Where to get piston, came, valves ect?

[Ajmboy]

Change the oil, once the oil brekas down it becomes thin and starts to pass into the combustion chamber which is the cause of the blue smoke. use only ATV oil

As for hesitation, DD is right..these things are notorius for getting floats stuck after sitting for a while. I had a 2004 kodiak before my King Quad.. sat for 3 months in a car port...had to unstick the corroded float pin.

I always use valvoline ATV oil that I can get at the auto parts store: Valvoline.com > Products > Motor Oil > Motorcycle ATV Oil

ATV oil has the needed addditives.

[fender13bender]

Change the oil, once the oil brekas down it becomes thin and starts to pass into the combustion chamber which is the cause of the blue smoke. use only ATV oil

As for hesitation, DD is right..these things are notorius for getting floats stuck after sitting for a while. I had a 2004 kodiak before my King Quad.. sat for 3 months in a car port...had to unstick the corroded float pin.

I always use valvoline ATV oil that I can get at the auto parts store: Valvoline.com > Products > Motor Oil > Motorcycle ATV Oil

ATV oil has the needed addditives.

Ok, I'll do that, but why is it only smoking when coasting? I don't understand.

And where is the float and what does it do? And how do I clean the carb?

[DirtDemon]

You need to buy a manual.

[Ajmboy]

Yes buy a manual. Here is a diagram of it:

2005 Yamaha YFM45FAT KODIAK 450 4WD OEM Parts, 2005 Yamaha YFM45FAT KODIAK 450 4WD OEM Replacement Parts - BikeBandit.com

#30 is the float and #13 is the pin that gets corroded usually

[fender13bender]

I have the stock manual

[DirtDemon]

You need a repair manual, like a Clymer or a factory repair manual. These are different than the owners manual.