Petcock issue? '03 WR450

All,

I had my '03 WR450 out for it's first ride since shimming the valves.  I had it up at elevation (Brushy Mountain, NC) and it ran like a beast...except it would randomly stall and wouldn't re-fire.  It was perplexing.  When it wouldn't re-fire, I switched the petcock from On to Reserve and it would light.  It ran great the rest of the day on Reserve.  

 

After that day's riding, I shut Off the petcock. The next morning, I just (habitually) set the petcock to On.  After about 10 minutes of riding, it stalled again and wouldn't re-light.  I put the petcock back to Reserve and it fixed the issue.

 

So I'm thinking that the petcock may be gummed up or there may be some foreign matter stuck in the valve.

 

The strange part is that I had given my KDX220 to a buddy to ride that weekend, and the same thing happened - luckily, I was there when he was kicking the crap out of the starter, and I switched it over to Reserve and it ran great.  Both bike run 93+ gas (with 15% Ethanol) out of the same pump, and I pre-mix my 2-strokes with Amsoil Dominator.

 

Can this just be a problem caused by Ethanol?  A few of my riding buddies run 100+/No Ethanol gas and they didn't have the same luck I did.

I'll be taking the petcocks off and apart later this week, but I was just wondering if anyone else has experienced something similar.

 

Steve

 

You found the problem the first time you went to reserve: open the gas cap and look inside the tank....it's full of crap, blocking the lower gas supply line.

You MUST treat your gas if you want your bikes carb to stay un-corroded. It only takes two weeks.....

You found the problem the first time you went to reserve: open the gas cap and look inside the tank....it's full of crap, blocking the lower gas supply line.

You MUST treat your gas if you want your bikes carb to stay un-corroded. It only takes two weeks.....

Thanks for the reply...I'm sure you're right.  I'll have a look in them on Friday and clean all the tanks out.

Do you have a preferred Ethanol treatment product? I see that Lucas Oil makes "Safeguard", but have never tried it.

Lucas is good.

Tri-G is good

Seafoam E is good


You need to remove the float bowl of your carb to look for further corrision

Lucas is good.

Tri-G is good

Seafoam E is good

You need to remove the float bowl of your carb to look for further corrision

 

Thanks for the list.

I had the carb apart prior to the last ride because it sat for a while - that varnish gets everywhere, but cleans up pretty easily.

I'm also told that it takes its toll on black/rubber fuel line.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now