01 YZ 426 won't start :cry

[Vetteman]

Alright guys I need some help from you, I got an 01 426 and it won't start up for me. I replaced the sparkplug and it still won't start up. Its getting spark and fuel but it won't start.

[cowboyona426]

When did you last check the valves?
Has the carb been cleaned or checked out?
How new is your fuel?
Are you following the proper starting procedure?
Have you done the ritualistic dance and sacrificed a chicken to the Yamaha gods?

[Mainjet2001]

Has the bike been setting a long time?
If so, it may need the carb cleaned.

[yzernie]

When you pulled the plug out was it wet with fuel?

[Vetteman]

Hey guys,today I had it running but it is hard to restart after it's been running. :Jedi

[kwmotocrosspunk]

check valve specs and decomp./hotstart valve

[Woody_393]

Yep, I would take a look at the valves.

[monkeyonahill]

yep, i give a 3rd on checking valves.. dang 4-strokes.. hard starting is a pretty good sign on a thumper of out of spec valves.

[Vetteman]

The weird thing is that when it runs it will run like crazy but just when it dies if im lucky it would start up but any other time it won`t start up

[Woody_393]

Have you ever adjusted you AP Timing? That could also be a problem. You could be squirting too much fuel or at the wrong time (or both) which could make for a tough starting bike as well.

I'd still look at the valves though -- It's pretty easy --> http://www.allthingsmoto.com/forums/...-valves-47609/

[Vetteman]

That ccould also be the problem because when I try to start it, it would backfire

[Woody_393]

That is also a symptom of valves needing adjustment.

[cowboyona426]

Don't twist the throttle when you are trying to start it!

[Vetteman]

It still would backfire even when I don`t touch the throttle

[Woody_393]

You could also have a header pipe leak which would cause that as well... But again, it still points to your valves needing adjustment.

[Macho393]

Originally Posted by Vetteman

The weird thing is that when it runs it will run like crazy but just when it dies if im lucky it would start up but any other time it won`t start up

sounds like your carb is jacked up.If its your valves it would start easy once hot, IMO.

[Woody_393]

Mine didn't start with a darn hot or cold when it was out of spec. It wouldn't idle, and it back fired like mad too.

[Vetteman]

Today I started it up while it was warming up the header pipe turned red-orange hot, would it sucking air cause it to do this or would a bad TPS cause it to do that?

[Woody_393]

running it for 5 minutes with no air flow would cause that. These bikes don't have fans to force the air through the rads, so they get pretty hot pretty quick if they are not moving.

[Vetteman]

Yea but, it turned in less than a minute. When I was riding it everytime I would pull the clutch in the rpm's would go up, the idle screw as low it would go without stalling the bike.