450x wont start! Im skeert

I've gone through the basics-- checked for spark,checked for fuel delivery,and I have both. It ran great the other day,and now nothing! I took the air box off and tryed starting fluid straight into the carb and still nothing but a single cough. carb problem--valve stuck? Any ideas?

check the valve clearances

Did you recently pressure wash your 450X? If you did or even if you have it take off the left number plate and check all the wiring and shake some of it and then try to start it, it hasn't happen to me but i've heard about it happening to WR's and i even saw a piece by the CDI that i wrapped in elec tape because i didn't like the factory job.

Just an idea?

well, I have checked the wiring. everything seems ok. plus, ive got plenty of spark.

How many miles\hours are on the bike? And during those miles\hours how was the bike ran?

lots of miles,lots of hours! Ive riden it pretty hard too. Ive always kept up with oil changes and little things but have never had the valve cover off.

Check the clearances, probably needs to be shimmed and then you will have a brand new @$$ kickin X again. :excuseme:

hold the throttle about 1/4th open. That should fire her up if its a valve issue. Besides that it sounds like the timing chain might have skipped but this very rare and even more rare on the x's

also, push start her, if she wont start then it is more then the valves. And you would notice the loss of compression using the kick starter if it was the valves

(Keep it Simple) A four stroke motor take four things to start:

1. Fuel

2. Spark

3. timing in speck

4. Compression

If you have these 4 things it will fire. ALWAYS start with the simplest thing first. In your case you have. Just check compression and timing you will find the problem. :excuseme:

I may be wrong, but isn't there a fuse that pops on these bikes?

I may be wrong, but isn't there a fuse that pops on these bikes?

If it has fire than it is not that.

thanks for all the info guys. if valve clearances check out ok, Ill be back on here with more questions.

well, guys, the valve clearances are good. how would you check the timing? from looking at pics in the book, everything seems to be in its place.

also, the compression seems normal.

this has GOT to be a carb. problem! right! anyone agee-disagree?

Yeah, probably the carb.

1. check the hotstart plunger in the carb: it sticks

2. check the accelerator pump cable mechanism: it clogs up

3. rotate the carb, lay the bike on it's side, take off the bowl, and take a good look for mung and drool in the jets: it's common

4. Will it try to start with 1/2 throttle? Then it's not the pilot, or needle

Good luck

wont start no mater what i do. I just checked in the bowl and I couldnt see anything. Everything looked really clean. I know this makes no sense. what else could it be?

I know you said you had spark, but recently after taking the tank off (and dragging the petcock thru the frame) my 450x, I knocked a wire off the coil. When I saw this and how easy it came off I thought I could have easily ended up with a problem similar to yours.

Yah, a friend of mine actually mentioned that, and I see what you mean. Thats a great thought but I checked mine out and its properly connected. I keep thinking its something stupid that Ive overlooked but I mean "COME ON!"how many things are going to keep this thing from firing at all! Im running out of options here and im dying to get out and ride. My last resort is to shamefully take it to the local Honda shop.

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