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Yamaha YFZ 450 is smoking


Sparrows

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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. :D

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

28hnclx.jpg

have a good one!

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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

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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 by DirtDemon
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