Wr450f hard to start

Hi guys ive just bought an 05 wr450f and its really hard to start i havent been able to start it by kickstart at all ive only ever really started it via roll start and ive started it once or twice by electric start but the battery keeps going flat (its got a brand new battery aswell) it rides excellent no faults when its going. its just had a full top end rebuilt and the valves checked by the previous owner who has given me the receipts to prove of the work its also had a complete gearbox rebuilt aswell.

Edited by Dirtbiker24

Are you starting using NO throttle? You should.

Choke if it's under 70 degrees.


Most likely you need to replace the pilot jet, and possibly clear the passage above it with fishing line.


If the carb has not be completely serviced ever, it might need it.



thanks mate, will pull it apart and have a look.

Here's how I start mine: Cold- twist throttle once or twice before cranking, pull choke, start with throttle closed.  Hot: start with throttle closed.  Remember the carb has an accelerator pump and you can easily flood it by twisting the throttle

I start my 03 the same exact way DPete does.

+1 on pulling the carb apart to look at the pilot jet.

Put a adjustable air screw on while your at it and if you have the money a JD jet kit.

Also check if the floating half of the slide is installed upside down. Mine was by the previous owner. Started hard and ran like crap.

And try a smaller leak jet. I think 40?

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