Bike wont start

I cannot get my bike started.. Its an 04 rmz 250 that just got a new crank, new shifter forks, new top end kit, my timing is dead nuts on.. Valves are in spec, Im getting spark, new spark plug. HELP!!! I followed the manual step by step. The bike doesn't even sound like it wants to fire..

Is it getting gas?

Try priming it by wicking the throttle 3-4 times before attempting to start it. Make sure you're getting a good kick on the compression stroke too. 

If not, it's probably time to look at the jets. 

Update. I got the bike started last night! But sounds like I have valve lash.. Even though my timing is on, my valves are in spec, and Im not jumping timing. Its making a fast clicking noise, but its been so long since Ive had this running I don't remember if this is normal or not?

If it's not too loud, that's completely normal. A lot of moving parts in a 4 stroke engine

Okay. That has to be the only answer to what I'm hearing then. But on another note, I found I can only bump start my bike. I can't get it to start if I just kick it. Put it on the compression stroke every time. Plug looked wet when I took it out but I kicked it over so many times I can see why. Something in the carb maybe?

Check the pilot jet, fuel screw, & idle adjustment knob. 

Where should he idle adjustment knob be set at? When it was started it ran great, it didn't idle high and it didn't idle low either. I never messed with the fuel screw and it ran great before the rebuild?

As a baseline, turn the idle adjustment knob so that the throttle slide is about 3/32 open. The fuel screw should be 2 turns out from closed. If the bike still won't start you will need to make some adjustments to each component, however, remember to only adjust one at at time. Also, I recommend reading as much info as you can about carb tuning. 

What do you mean 3/32 open?

3/32 inches 

So I checked my jets, spotless.. I still put some carb clean  through them to be safe. My fuel/air screw is set to factory spec. I went by the manual when doing the carb and It still doesn't start when kicking it over. Put it on the compression stroke everytime, kick with choke on, kick it giving it alittle gas, still nothing. Run with the bike down the driveway, bump start it and it starts fine??

Does the problem only occur when the engine is cold or does it not want to kick start even with the engine being warmed up? Assuming the valves are in spec, check the choke and hot start plungers to make sure they are not stuck in one position. Check the float height in the carb bowl. Turn the fuel screw out 3-4 turns and see if the bike is easier to kick start. If the bike starts with the fuel screw out that far, a larger pilot jet is needed. 

The bike does not kick start at all. I can kick it over fine, it just will not start up. If I bump start it, it runs fine.

Sounds kind of like a fuel issue. In addition to the things I mentioned in my previous post, also check for air leaks around the carb. 


What size pilot jet are you running? 

Edited by fulton246



Im not sure. Its the same jet that was in it before. How would I need a bigger jet? Not disagreeing with you, im curious.

Try starting it with no gas. The accelerator pump will be squirting fuel and your motor will be getting too much fuel. That could be why your plug is coming out wet.

Air filter clean?  Try removing your # plate next time to see if the added air helps.  Mine hasn't been starting as easily lately due to all the dang humidity.

Ive tried it without giving it gas for a ton of kicks. Still nothing. And That's how I tried firing it up, with out the # plate.

Have you tried it with a clean air filter installed and # plate and seat installed?  If your jetting isn't close it can make the difference.


So you can get it started by pushstarting it?  Then you can ride it all you want?  But it won't kickstart?

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