426 starting problem

[mustang938]

I have a 2000 yz426fm i just bought it doesnt want to start by kicking it the only way it starts is by popping it in gear as you coast it down a hill or pull it. also it doesnt stay running unless you keep the rpm's up any help guys thanks. It doesnt really seem like the spark plug is sparking alot wasnt sure if this could be the problem

[DeeCee]

The early YZ's like to have very clean carburettors to start well and run sweetly.

Sounds to me like you just need to take the carburettor off and give it a good clean out. Make sure you blow out all the passages and the jets are clean. Also check that the fuel screw is around 1 and half turns out. Once you get it running you may need to adjust it again for best conditions.

Also flush the gas tank to clean out any dirt or residue that may be in there.

[cowboyona426]

1. Clean carb

2. Put fresh fuel in the bike

3. Clean air filter

4. Install new plug just for kicks

5. Check valves

6. Learn the starting drill if you don't have an auto decomp cam

After that you should be able to start it no problem.

[kz2zx]

Get a VOM (volt-ohm meter) and check the stator. Section 6 of the manual.

[skthom2320]

Here are other things to check which would give you the same symptoms:

1. check that the vacuum release plate (it's a plate that is attached to the slide in the carb) is installed correctly. It's very easy to put this back in upside down. So a search here on "slide plate" If I remember correctly you can see a little "M" stamped on the slide if it is not upside down. I would just pull the carb loose and have a look. I think you can do that without removing the cables.

2. make sure your fuel screw is actually present.

[mustang938]

im really starting to hate this bike lol. well i cleaned the carb, air filter installed new plug and i also checked the valves everything looked ok. Like i said it starts up if u coast down a hill and bump start it other than that kicking it forget it.i also adjusted the idle screw becaus it wont idle i tried 1-1/2 and 2 turns out. thanks everyone

[Dirtbagger]

Just bought a 2001 YZ426. What is "the drill?" The guy I bought it from started the bike in two Kicks. (it does have a decompression lever).

I have since worn my leg out trying to get it to fire. Sounds like it is going to start then dies out. Any tricks, other then getting the seller to come over and start it every time I want to ride.

[kz2zx]

Check the common question thread, there's some links to videos of some Yamaha racer dude or other showing you how to start it.

(yeah, it's tongue in cheek. But the vids exist).

Oh heck, I'm being helpful, here

[cowboyona426]

"THE DRILL"

1. Make sure gas is on

2. Choke for a cold motor, hot start for a hot motor. If the motor is cold, a few blips of the throttle MAY help it- each bike is different and some get cranky if you blip the throttle.

3. Squeeze the front brake to keep you from twisting the throttle while you kick.

4. Kick the bike through gently until the piston comes to TDC (can't easily push it any more with your foot)

5. Pull decomp lever to the bar

6. Push the kick start down 1-2" and release it

7. KICK like you mean it!

mustang- don't give up, once you learn to start the bike you'll love it. Do as skthom2320 suggested and check the plate in the carb slide if you had it out while cleaning the carb.

BTW- skthom2320 I haven't seen you around in forever- nice to see another "old school" member hanging around ?

[skthom2320]

im really starting to hate this bike lol. well i cleaned the carb, air filter installed new plug and i also checked the valves everything looked ok. Like i said it starts up if u coast down a hill and bump start it other than that kicking it forget it.i also adjusted the idle screw becaus it wont idle i tried 1-1/2 and 2 turns out. thanks everyone

Did you confirm that the vacuum release plate is correctly installed? Usually "cleaning the carb" results in putting this back in upside down!!!!

And the bike won't start easily, it will sputter, and it will need a lot of throttle to stay running. Souind familiar?

[skthom2320]

BTW- skthom2320 I haven't seen you around in forever- nice to see another "old school" member hanging around

I'm here! Been riding CRF's for the last few years so not much reason to check out the yamaha side. Thanks for the "Hello!"

[cowboyona426]

I'm here! Been riding CRF's for the last few years so not much reason to check out the yamaha side. Thanks for the "Hello!"

I think I remember you going to "the dark side"... wasn't it shortly after ShawnMC did the same? I'm still on a Yammie, but the 'ol reliable 00 got replaced by an 06. I still don't know if that was a smart move or not, but the 06 is treating me well so far (I just can't stand the damn pushy front end and haven't had the time or $ for a revalve yet).

[grayracer513]

I just can't stand the damn pushy front end....

Cowboy,

Did you catch this post?

https://www.thumpertalk.com/forum/showthread.php?t=657523

[cowboyona426]

grayracer- no I hadn't seen that post, however...

I run Windham bends bars already close to the zero position I believe with 10mm risers and a Kenda Washougal front tire. The first few rides the Washougal made a ton of difference over the previous Maxxis Maxxcross S/I I had, but on the last ride I took it felt like I was on marbles all day. Stock height on the fork tubes, stock clicker settings, and I have EZ bleeders on the forks so I know they weren't charged up with a bunch of air. I'm about 6'2" with ape arms and long legs. If I could just get the front end to stick...

[Dirtbagger]

Thanks for the info.

Drained the gas from the tank and carb, new gas in and two kicks later away it went. Not sure how the bad gas got in there but lesson learned.

Thanks again!