Yamaha YFZ 450 is smoking

[Sparrows]

Hey guys, anyone remember me? *crickets*... anyways! along awhile i go i used to post and talk with you guys i was running a modded 400ex, 465 big bore, cams ect ect, I thought it was fast, lol... Traded it for a camaro to pursue drag racing, blah blah didnt have money nor time to put into the car, so TODAY i traded is for a GNCC race ready 04 yfz450, Cams, hiper wheels, Lone star axle, hole shots, list goes on and on, over 15k in this machine, runs pretty good, runs on 110 octane...theres so much to list on this its redonk. :disgusted: Expensive! Anyways, need to run all new fluids through it, But im back into the community and ready to ride it already! this thing is beyond fast. i thought my 400 was fast then got on this and first gear is just dissssgusttting.

dont read the paragraph, to make a long story short, I miss this sport more than anything..

have a good one!

[Stoopidbot1]

Very nice...welcome back!

[Sparrows]

its blowing a bit of white smoke, but it needs an oil change and new gas, could that be the culprit? or rejetting?

[Stoopidbot1]

Unless there is oil in the gas I would say no. Rejetting wouldn't hurt. Exhaust packing could be saturated.

[Sparrows]

Yeah, it really doesnt smell like oil i dont think, i know it needs a spark arrester, could it be the packing? it blows smoke like no tomorrow, but it runs perfect, starts right up doesnt chug or anything. Air/fuel maybe?

[Stoopidbot1]

Air/fuel is possible but it sounds more like you need to repack the exhaust. Open it up and you will know.

[Sparrows]

Ah fair enough, its a rossier pipe. i think it may be a full exhaust not sure on these. new to this yamaha blah blah, except my old as* blaster i had way back when

[Sparrows]

So i stuck my finger in the hole.....lol Felt the featherly like Stuff popping through the exhaust "little holes" Lol kid terms here. But i think that might be it, if not then i have no clue, finger came out black as hell tho..

[Stoopidbot1]

It is easy to replace. You can get exhaust packing at any bike shop or online store. But check if Rossier has a specific one.

[Stoopidbot1]

So i stuck my finger in the hole.....l

I hope you bought her a drink!

[Sparrows]

Haha, Yeah i sure did, i hope this is nothing major. But it cant be i would think because it runs fine and everything, runs on 110 octane, maybe the wrong jets for the fuel. or just bad fuel.

[Stoopidbot1]

Yeah...start simple and cheap. Worst case is your rings and if you catch it early there is no damage to the piston or cylinder. So get that packing and see if that helps it out.

[Sparrows]

yeah lets pray its nothing to bad, lol shouldnt be.

[Stoopidbot1]

I doubt it's anything major. It looks like it was taken very good care of.

[Sparrows]

Yeah i mean, thousands poured into it i doubt its anything major

[Sparrows]

Yeah just texted the guy, said its just thin old oil and valve seals are wack from sitting so long, said this is the longest its sat. said he drove it up the street today and said its its normal "fast" and not to worry. pretty straight up guy. good deal.

[Stoopidbot1]

Sounds good.

[Sparrows]

This might help other people that could have this question too.

What type of spark plug to run when using race gas 50/50 or 60/40, I have the big bore 470, port and polished head, stage 1 cams. Running 110. figured why my bike is smoking is because the old plug not sparking hot enough to burn the 110. btw its an 04 yfz450

[DirtDemon]

What does the smoke smell like?

The heat range of a spark plug refers to the amount of heat that it dissipates from the cylinder, a hotter plug will dissipate heat more slowly keeping it hotter in the combustion area, a cooler plug dissipates heat faster and thus the combustion area will stay cooler. It has nothing to do with the power of the spark. However, high octane race fuels burn cooler, so a hotter plug probably won't hurt anything, but the increased compression should make sure that the fuel gets burned as it should. If you aren't burning fuel completely, the smoke will most likely be black. If it is oil burning, the smoke will be blue. You said the smoke was white, which indicates water/antifreeze is getting in the cylinder, that is usually caused by a bad head gasket, but it could be a cracked water jacket in the head or cylinder, or it could be a warped head. Smell the smoke, antifreeze will have a kind of sweet smell when it burns.

Edited August 5, 2009 by DirtDemon

[DirtDemon]

By the way, I merged this with your spark plug thread since the topic is still kind of the same. I also moved it into the Yamaha forum since this has turned into a technical help thread.

[Sparrows]

Just smells like gas.

[Sparrows]

Starting to think it needs the water pump seals and shaft replaced, if so thats not as bad as i thought.