WR450f starting problem

I have a Yamaha WR 450 F 2004 it starts vary hard when it is cold but runs great and starts good after its warmed up what can i do to fix this.

I have a Yamaha WR 450 F 2004 it starts vary hard when it is cold but runs great and starts good after its warmed up what can i do to fix this.

More info needed.

Jetting

Condition

State of tune (pipe airbox etc)

Most common issue is a clogged pilot jet.

Starting fluid.........................

Check the valves, if there out of spec it will make it harder to start.

No. No. No starting fluid!!! And it's usually not the valve clearances if the bike is hard to start while cold, only when it's hard to start while warm. I'm guessing your still using stock jetting? In Maine?! In October?! You see where I'm going with this!!! Heck, stock jetting is too lean in Arizona in the summer!!! Besides the jetting, what method are you using to start the machine? I've got a JD jet kit in mine, but here's my routine:

1. Ignition on, Fuel on, Choke on.

2. Three twists of the throttle.

3. Hit the starter button, or kick it over.

4. Almost always, the bike fires up within three engine revolutions.

5. After about 3 seconds, I can take it off of choke unless it's something like 10 degrees or colder out

6. Let the bike warm up until you can feel some heat coming thru the cylinder wall.

7. Go ride!!!

don't know I just got that dike a month ago. But I turn it on twist throttle twice with choke out then crank it over turns over 50 times before it evens barks than it starts runs great and when I shut it off and come back out in an hour or so it starts right up.I'm going to go through the Carb what should be the sizes of all the jets? And were can I get the ones I need

is the bike stock? when mine was stock it was hard to start change the leak jet and main jet as needed for your elevation. try a AIS block off kit if applicable for your bike. it did wonders for mine

My elevation is 205m or 615ft so how do I know what jets I need

My elevation is 205m or 615ft so how do I know what jets I need

You still have to answer the first question

i am using a 50 pilot jet and a 172 main id say you could run the same. my bike was 45 pilot annd 162 main jet stock

i am using a 50 pilot jet and a 172 main id say you could run the same. my bike was 45 pilot annd 162 main jet stock

Those jets are too big unless you have a modified motor (which you still haven't divulged).

45

165

NCVS needle

50 leak

Brass fuel screw @ 1.5

tight valves?

my fuel screw is 2.5 and my bike is all stock just uncorked those are the jets that the AIS block off kit came with from yamaha for my wr450 it runs great

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