426 won't start anymore and backfires

Just picked up a 01' yzf426, been riding around for the last couple days no problems:thumbsup: . Tried starting it today and it wont fire up:mad: , I have the starting procedure down pretty good:prof: . Every 4-6 kicks it will backfire. Air filter was a little bit dirty, cleaned, still won't start.:thumbsup:

Try this with a cold bike:

1 - Push IN hotstart and choke

2 - Mount bike

3 - Turn on gas

4 - Pull in decomp lever and kick 3 times

5 - pull choke lever

6- Give throttle 2 blips, maybe only one

7 - Find TDC and kick (repeat a few times)

If it doesn't start, then replace the plug and repeat procedure. Hope this helps.

Before starting it- when was the last time it was started before that, or how long was it sitting?

If this is the case, the carb could be green. It would need to be clean and those jets could be getting plugged because of this.

Take off the bottom bolt and check it out. It's easy.

I say this because I bought a 426 2002, 9 months ago and this was the case.

Let me know.:thumbsup:

No, that didn't work and I'll have to wait until tomorrow for a new plug.

Last time I rode it was yesterday, it ran perfect all day.

Check to see if you have a good connection at the coil..

I'm just a dumb jail gaurd, how do you check the coil?

OK, I've moved the thing into my livingroom, it's cold outside. I gotta this this fixed soon before I get slamed by snow.

It's right under the top of you gas tank. The tank will need to come off. You can follow the Plug boot, up.

If its not the plug, sheck the valve clearences. My buddy had the same problem with it backfiring when trying to start and the ex valve was a bit tight. Good luck.

It could be plug. If it's cold it's really simple to kill the plug. First the bike starts and stop and after that it backfires every 4-5 kikcs.

It did start for about 1-2 seconds before this problem occured yesterday then it was done, I'll pick up new plugs on my way home today, I hope it works.

OK, I've moved the thing into my livingroom, it's cold outside. I gotta this this fixed soon before I get slamed by snow.

sorry Navy I could not help but to chuckle when I read this......does this mean that the 01 YZF will be a permanent fixture in the living room all winter? :ride:

Reminds me of apartment living days....the chicks dig MX bikes in the livingrm....until you marry one of them.:busted:

on the issues:prof:

it may just be flooded and/or fouled plug - empty the carb bowl on the bottom of the carb with a 17mm wrench, preferably not inside your house, change the plug, it is a NGK CR8E - I hope you have the plug wrench for the yzf. The Manual will help you immensely

it could be jetted wrong - did the temps take a drop when you tried to start it after the day it ran great? These older yzfs are temp sensitive

or it may need a valve adj? Chances are if nothing above solves this it may need servicing.....

The starting drill is key.... just a couple of blips on the throttle before starting it up...never twist and kick....:thumbsup:

and keep those prisoners in line

Unfortunately no, I can not have it in the house when my Girlfriend gets back into town, I figure if she’s out of town I can run the house anyway I want, until she gets back of course. And if that means a motorcycle in the living room then YAY for me!

There was no big drop in temperature, just a steady cold. Hopefully I just flooded it, and the new plug I’m picking up will bring it back to life. I do like it in the living room though, looks good, and I can watch TV while I work on it.

Unfortunately no, I can not have it in the house when my Girlfriend gets back into town, I figure if she’s out of town I can run the house anyway I want, until she gets back of course. And if that means a motorcycle in the living room then YAY for me!

There was no big drop in temperature, just a steady cold. Hopefully I just flooded it, and the new plug I’m picking up will bring it back to life. I do like it in the living room though, looks good, and I can watch TV while I work on it.

hey what they don't know, doesn't hurt them.........or hopefully, never comes back to haunt you:thumbsup:

My bet is the plug. I had the same thing happen. New plug cleared it up on the first kick! Hope it is the plug as that's the easiest thing to fix!!

YAY It was the plug. And I got to start my bike in the house. I would like to know why they made the plug so deep in the motor, it's dumb unless there is a good reason, and getting a deep socket and ratchet in there is not fun. I can change the plug trailside, on my cr250 in about 90 seconds, are all 4 stroke plugs so small and hard to get to? Funny thing is the plug I took out didn't look that bad. A little bit of black build up, but not bad.

YAY It was the plug.
Isn't that amazing?
I would like to know why they made the plug so deep in the motor, it's dumb unless there is a good reason, and getting a deep socket and ratchet in there is not fun. I can change the plug trailside, on my cr250 in about 90 seconds, are all 4 stroke plugs so small and hard to get to? Funny thing is the plug I took out didn't look that bad. A little bit of black build up, but not bad.
Look at a YZF head flipped over and tell me where else you would put it, and how much bigger you think it could be. :thumbsup:

can anyone tell me what size the plug wrench is for the 426 as i have a funny job getting it out with the tools i have.

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