this should be yzf anonymous


I will have to agree with you on the special tool and the removal of the gas tank bro.

I only wish you'd give me the bike for 2 hours and let me fix the carb up for ya....I had the same problem but that was a year ago and I'm totally in love with this bike.....other than me stalling once in awhile big blue is perfect.

Please try to get your dealer involved. I'd vent that anger toward them....they profitted from your hard earned money...MAKE them perform to your satisfaction.

Don't give up bro.

As said above, I think that your bike is the exception and not the rule. I fall over all the time on my '01 and I've never fouled a plug because of it. I'm sure if you check the CRF forum you'll find at least one person there who has had similar trouble with their CRF.

As for the spark plug, all you need is a regular spark plug socket with a rubber insert in it and an extension with a swivel end (Sears has them for a few dollars). Makes it a 2 second job once you have the tank off.

Sorry to hear about all your problems. :)

I've had no problems with both my bikes.

Both have been awesome.

Good luck. :D

man mike, i had a hell of o time when i first got it because i would give it gas when trying to start it. the result? a fouled plug almost every time.then i read the starting procedure in the manual and it has started on the first kick almost every time. i have not fouled a plug since. i live in bend. if you are ever out this way let me know and we'll ride. DISCOPETE@HOTMAIL.COM

Mike I hate to tell ya this, but YOU fouled the plug more than likely, rather than the carb fouling the plug. If you hit that trottle even just a little trying to start it, its problem city and your the mayor. My suggestion: put your throttle hand on the brake resi. when your kicking at it. Im betting your fouling problems disappear. :)

Mike, I've had my 2002 426 for about two months now. The first time out it took me 15 minutes to get it started. I had a difficult time for about the first four or five rides. Reading Doug Dubach's starting instructions on the Yamaha website help me quite a bit. I have the drill down pat now. Now, the bike starts 1st kick when cold, or hot restart. 1st or 2nd kick after a fall. It's crucial to follow the starting instructions pefectly. The bike is broken in now, which has helped a lot I'm sure. I'm very happy with the bike now. My only small complaint is that, if I fall during a moto and the motor dies, I have to go through the starting drill. By then the pack is about half way around the track. Now I just need to get better at railing the rutted corners, instead of highsiding now and then. No regrets here. I did at first, but not anymore.

By the way, I rode Elsinore's through the 70's as a teen and never had a problem fouling plugs.

Damn, Mike, I know, and have raced with for years, the service manager at Action Motorsports (Steve) and he knows more about bikes than any 20 of us. My guess is that you did NOT talk to him. With someone as vocal as you, I'm somewhat hesitant to send you to him. Steve rocks, so contact him and don't screw it up, please.

I also concur that you're probably a leftover 2-stroke guy and possibly you're flooding it. I had the same initial problem. Also, start taking off the choke asap after it's cold started. My 2k version always starts if you follow the procedure. Always. Hell's fire, I'm still running the stock plug even!

Good luck,


I crashed hard a few weeks ago while racing a guy on a CRF. He stopped to help pick me up off the ground. We sat there a few minutes and then I kicked my bike over on the second try. The CRF guy took around 15 kicks to get his bike to start (all the while cussing at it).

I have had my bike for 6 months and have made only minor adjustments (fuel screw extension, E-series pipe, Pro tapers). I still have not pulled out the spark plug. The bike starts every time (and sometimes I roll the throttle when it is cold and it still starts).

I'm surprised you are having such difficulties with a 2002. I would definetly give the dealer an earfull of grief.....good luck.


I can relate to exactly the way you feel. My '02 426 runs awsome with a new plug until it gets to full temp. Then starts missing, popping and coughing until there is enough carbon on the plug to foul. This usually takes about 5-8 minutes I guess.

This is what I have tried so far: carb, cdi, coil, stator, fuel, all from another bike, also checked the timing. Nothing has worked. Only thing left to do is check the valves which will be done this weekend. I'm sick of working on this thing. What else is there? I never fouled a single plug with my 2000. My dealer is to far away to be of any help.

Currently I have a $6k, 250lb piece of junk in my garage. If it's not something in the valvetrain, then what options are left? I'd feel great about trading in my '02 w/about 10 hours on it. So economical and all. Why change tires when you can change bikes?

Anyone have suggestions?

I think I will go back to the dealer and see what they can do. I have the starting proc. down pat. I don't touch the gas when I kick it. It's not that I don't like the bike when it's running, it's when i have to deal with all this other stuff. I am not accustomed to fowling plugs, I had a Cr that never foulded a plug ( I had it 11 months). I don't go around lugging the bike either I scream the thing. And I am not that vocal in real life, I am just pissed, you have to understand that I love to ride dirtbikes, I am a college student so money is an issue and I am just a little aggravated that my first new bike ever fouls more plugs than every bike I have ever owned put together ( i've had 4). Well i'll let you guys know if I get anything positive done with the thing.


Go buy a RED bike ,2smoke or a bike that has a magic button!!

If you have not read an article on how to start these beasts, than you’re an IDIOT!. Everyone knows there’s a drill to start these bikes. Every magazine talks about it. Even Yamaha’s main web page has an article on how to start these beasts, which should tell you enough.

If you have read articles on how to start a YZ 4stroker than please accept my apology.

After personally owning a YZ400 & YZ250F, I thought I'd now how to start a hot CR450, during a race I stalled the Honda and this bike needs the same friggin drill, if you panic, your toast.

Like Shawn says, you CAN'T touch the throttle when starting the beast. Also, when you’re sitting on your bike in the garage bench racing, you blip the throttle, you’re flooding the engine.

4 strokes aren't for everyone.

02 426. I've never touched anything, not even the fuel screw. It starts 1st or 2nd kick after sitting a week or more, and 1st kick every time even without the hot start (sometimes I even forget that it has a hot start button). I actually wore out the plug that came with the bike. You've received some very good tips, take a deep breath and try them. DON'T TOUCH THE THROTTLE and remember to put it at top dead center (not an inch past it or before it). Good luck.

Get a 2 stroke there 30lbs lighter and way easier to handle I had a 2002 yzf 426 mine started pretty good but at the track I had to adjust the carb to much and to much weight for me.

Next week- I begin looking for the nearest dealer of orange plastic. Get it? Get it?

Anyone interested in parts? I have several new wheels and new rotors, many misc used rotors. Lots of other stuff too.

My brand new 426 fouls plugs like a 1979 Elsinore with more oil than gas in the tank. When it's cold out side the worthles piece of **** wont start. When I was at the track I crashed and had to spend 3 motos off to the side of the the track kicking my bike over while all the cr 450s flew by me (I had to push it up a 40 yard hill to the parking lot). To change the god dam plug you have to take the effing seat off and use I special tool that some effing inbread at yamaha desighned. I can honestly say I have never owned a bigger piece of **** than the 426, I would rather drive a god dam hodoka. I think it's time we all came out of denial, cried for a fiew minutes, and hauled ass to the honda shop to get a real bike.

P.S. I know what your going to say, my bike isn't jetted right, try the blue wire mod... You guys are missing the point, you should not have to do all that **** to a 6000 dollar bike. Jesus Christ I have been working on my bike more than I have ridden it. I am going to go bang my head against the wall, see ya.

My '01 is bone stock except for the triple clamp and handlebars and she lights off 1st kick 99% of the time, once in a while it takes 2 kicks, no fouled plugs, no blue wire, no BK, etc. I know it's not an anomaly because several friends have stock bikes and they all light off like mine. *shrug*

The only time she died and wouldn't start on me was the time I left the petcock turned off! DOH! That was rather embarrassing.

[ May 02, 2002: Message edited by: BigLou ]

I forgot to say something, when I went to my dealer (action motorsports) I went and talked to a mechanic, I told him my new bike fouls plugs and it probably needs rejetted, I was looking for some suggestion as to what jetting to run, he looks me in the face and says ( the 426 is a powerful bike and the carbarators are really touchy) That is a different way of sayin you bought a piece of **** . I felt like punching him in the nose, walking up the sales man that sold me the bike and kicking him in the nuts and walking out of the store.

hay mike i got some good advise: (1) if its cold out side put your f---ing bike in the garage.(2)stop riding like a jack-ass, it sounds like the bike is to big for ya.

dam dude,

you seem pretty pissed. My bike is having problems at the moment but the last thing I am going to do is sell it. If you are gonna go two-smoke then you are gonna have same problems eventually and a hell of a lot more maint. Just take the time to read over the posts in this forum and I am sure you can find plenty of info. to help you get it runnin right. Their is probably someone in Oregon on this board that can help you jetting wise. Do some searches on fouled plugs! You could have an over oiled air filter. Have you tried pullin the carb off and cleanin it very thoroughly? Sorry you are having such a bad experience. Hope you work it out!! :):D

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