Yz426f being a female dog

Hey peeps,I'm new on thumper but i have been reading as guest for long time.My problem is, it almost never wanna start...This is what i did till now.New spark plug.(it sparks)Valves adjustement.Cleaned air filter.New oil filter and oil.Fuel filter installed between tank and carb.pilot jet from 52->45Fuel screw 1,5 turns outI am really getting pissed about it because i cant find the problem.I hope you guys can help me.

I owned a 2001 and I had the same problem search on you tube on how to start them. That's a big reason why yamaha stop making those bikes because the were a bitch to kick when cold and hot. In motocross they were good bikes until u stalled them and that was it, your race was done unless u get lucky and it starts up again on first kick and there has to a miracle for that to happen. It left me stranded out in the desert a couple times because when I shut the bike off to take a break the bike wouldn't start up again when hot I even used the hot key switch still didn't work but the bike ran like a raped ape when it was running. I ended up selling it because of the problem, I got tired of it now I have crf450 and its great and a lot more power so good luck with yours I heard you could put a hot cam for the intake its about $150 to fix the problem but heard it doesn't thats an option if u haven't already done it. They're reliable bikes when they are running ill give them that.

This one was my dads typo it was his and I had my 450 at the same time and he sold it because it was just a pain in the ass but it look nice and ran really good after I got it started.


So how does it start up, easy? I never knew how it ran with a hot cam on there?

no it's still hard to start since i had problems with my carb (there are also pictures in this thread about the damage in my carb).

But i can just kick it without decompression lever.

Yeah take a irwin vice grip that can get in that small space to take the screw out, thats how I deal with stripped screws.

When u put the float back on just make sure the float and needle move up and down real easy without getting stuck and take and spray brake cleaner in every hole and make sure when u spray that it comes out some other hole smoothly. And u can get that screw out real easy with a vise grip be patient you'll get it.

Yes i got it al fixed but the problem is the well from the pilot jet that is partly broken of that is why i bought another carb

Why?? just had to buy another jet at a parts store or Internet just saying

Did u say ur bike is not idling off choke all you have to do is clean your jets out with a wire the might full of crap and u dont have to take the top of the carb nothing internal to fix that take apart just the bowl take a flat head and screw out the jets and clean them with a wire and spray brake cleaner through them and try it then.

You should read the whole thread. Its idling good and everything is clean. The broken piece cant be replaced. Its the body of the carb

Ok good luck

I wonder how someone broke that? Show me a pic of the new carb?

Yes i got it al fixed but the problem is the well from the pilot jet that is partly broken of that is why i bought another carb[/quote

I thought u ment the jet itself sorry

thx for the explaination ^^ I have hot cam and decompression cable and lever removed but there is a piece broken in my original carb, so i bought a 06 yz450f carb, that i received today.

but i miss hot start assembly.


Grey Is this complete?




Nope, wrong stuff.  The one in the picture is a decomp lever and cable.

Oh ok. I just got the item/price list. Its 146€(200$) for everyting that i need for the hot start :/

If you have removed your OEM decomp lever, you should be able to use that to operate the hot start cable.  Saves a little bit.

I have the OEM cable and lever from the decompression assembly. That would save a bunch if that works also

The lever should, but the cable won't.

This is the connection from the carb with the air filter box. It does not seal off, on my old carb there is the black rubber bolted on. Not on this carb. Does this carb have no rubber or should i order it?


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