Popping issues after winter storage - 08 450f

I put my RED STICKERED (yes, California) 08 YZ450F away in June when it was approximately 70-80 degrees and it was running well. I pulled it out this week and started her with the old gas ... some popping as though it's very lean. Figured it was the old gas so I went on with getting her race ready - checked valves, replaced oil/coolant/lubed bearings/etc and cleaned her up. Started her again and the same irritating pop on decel. The gas I used this time was old but it was in a metal race gas container so I figure it's still good. I cranked the fuel screw open about 3.5 turns and it gets better but still pops a bit. This usually tells me to go up on the pilot but I'm already at 48 and it was running fine prior to storage (btw, running 160 main, stock everything else at about 1800 ft in Santa Cruz Mtns ---- about 95 degrees today).

What gives? Carb needs cleaning? Air leak somewhere?

I would go buy some fresh gas.

The new and improved fuels seem to fade very fast these days.

Did you drain the carb of fuel while it sat for that long?

If you didn't you may need to clean or replace the pilot as I have heard they are very hard to clean.

3 and 1/2 turns is way too far out for the pilot/fuel screw. People on here say 2 1/2 is about as far as you should go.

Yep, new gas, and clear the dried lacquer deposit out of the pilot jet.

Steve - no, I was lazy and didn't drain the bowl. Instead, I started riding my green stickered YZ250 and forgot all about it.

Gray - I think you're right. Will get some fresh gas tomorrow and let the pilot soak in WD40 or similar tonight.

Thanks guys.

That was the ticket --- at least one of those suggestions was. I soaked the pilot jet all night and then blew it out with compressed air. Also put in new gas. Started first kick and popping is gone. I am now ready for opening day this Thursday, Oct. 1. Hope my boss isn't a T'talker :-)

Thanks for the help guys.

That was the ticket --- at least one of those suggestions was. I soaked the pilot jet all night and then blew it out with compressed air. Also put in new gas. Started first kick and popping is gone. I am now ready for opening day this Thursday, Oct. 1. Hope my boss isn't a T'talker :-)

Thanks for the help guys.

Sweet,happy to help.

If pump gas sits around for more than 30 days you might as well put it in the car or lawnmower.

You sure gray isn't your boss?:banana:

Have fun on opening day!:busted:

If pump gas sits around for more than 30 days you might as well put it in the car or lawnmower.

Do your car a favor and keep that stuff away from it, too.

I have seen tons of issues related to the growing use of E10 fuel. The stuff is NASTY when left sitting in fuel tanks for extended periods. The E10 residue is corrossive, and actually "cleans" away debris on the insides of fuel systems. It's not so critical on 4 strokes, but I don't have enough fingers and toes to count how many 2 strokes have melted down from E10 skank partially clogging the main jets. Here's a product I HIGHLY recommend for combating

E10 fuel in storage:

http://mystarbrite.com/startron//content/view/93/123/lang,en/

One 16oz. bottle treats 256 gallons, and a 16oz bottle is about $17, so it's cheap piece of mind after you do the math (especially if it prevents a 2 stroke KX,CR,RM,YZ meltdown)

It doesn't have to be E10 to go stale. I've seen California pump fuel in customer's cars that was supposed to be two weeks old that didn't produce any vapor pressure, and could barely be ignited with a match.

It usually lasts longer, but when anything like this comes up anymore, the fuel is one of the first things I think of.

my bike wasnt even close to start after less then 30 day of sitting (the raptor did start with even older fuel).

but with new gas and a clean bowl it started first kick :busted:.

thank you tt.

It doesn't have to be E10 to go stale. I've seen California pump fuel in customer's cars that was supposed to be two weeks old that didn't produce any vapor pressure, and could barely be ignited with a match.

It usually lasts longer, but when anything like this comes up anymore, the fuel is one of the first things I think of.

The problem with the lifespan of the fuel,is that we don't know how long it has been in the gas stations storage tank.With the economy the way it is premium pump gas is not selling as fast as it used too. I buy only what I plan on using that day.I don't use my 5 gallon gas can anymore,most rides I just top off the tank on my bike.

E10 must be the high Ethenol version eh?

Many riders here in the SE USA are having similar issues with this new gas. 2strokes hate it, and I have heard of gumming issues in all carbs if Ethenol gas is left in the carb for any length of time......you got to like corn huh? :busted:

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