Smoke coming from bottom of radiator area.

Hi all.

I have some smoke coming out of the bottom of my radiator. It's hard to tell where it's coming from because it's right where the frame hides part of the bottom of the radiator.

I know smoke can come out of that area a bit if you are really working the engine hard but this is happening even when the bike is just barely being ridden. I topped off the coolant and it still happens.

Any ideas? Do I have a cracked radiator?

I know very little about how to work on the bike so really need some diagnostic help here.

I'm distressed about this!

Thanks all,


Where there is smoke there is fire!! That to me would rule out the smoke factor cuz you still have your legs intact. My guess from what you said is that you probably have a very small minor leak that is not big enough for a water molecule but is big enough to steam. Use some super sudsy warm water to spray or dribble on the bottom of your radiator (must be warm to hot or it will cause it to steam) and try to locate some bubbles and then take it to a radiator shop to fix. Good luck, Jason

What year is the bike?


Sorry, forgot the details: 2003 WR450.

Kick start side? If so, could be the plug that goes in the head where the decomp. lever was on the 02 and earlier models. Engine oil making smoke.These plugs can come out prtetty easily especially if you crank case breather vent is kinked at all. If this is your problem the TT store sells a really nice alu;minum plug with a seal and the preexisting bolt in the head holds it in place. Hope it is an easy fix.

Been slammed with work so can't investigate yet. I'll look this weekend.

It is indeed the kickstart side. So, it could be a loose bolt or something that I need to replace with that freeze plug?

It's just a rubber coated plug that is pushed in the hole where the decomp lever used to go. The bot is on the side of the head and it's purpose was to retain the decomp lever. Now it just fills a hole but, it iis utilized to retain the aluminum plug that I previously mentioned.

It is indeed the kickstart side. So, it could be a loose bolt or something that I need to replace with that freeze plug?

Click on the pic links I posted. I've circled the area to look at.


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