carburetor removal / jetting advice

Guys - my bike (03 YZ450F) seemed to be running lean with a lot of popping and backfiring so I installed the JD Jet Kit. Blue needle 3rd clip, 170 main, and the stock 42 pilot. Now, I can't get the bike to start :) I went completely back to stock and it still won't start. I made sure the gas is fresh, new, plug, fuel line connected but can't get 'er going.

My first thought is that I possibly have dirt in the carb somewhere. In order to clean the carb, do I need to take it completely apart? I'm concerned with disconnecting the wires.... is that necessary? what do you suggest?

Also, if I hold in the hot start lever it will turn over for a second... does that mean it is too rich? Any suggestions?...

How about the obvious, turn the pet cock back on? If not, did the float get jambed from the changes?

Is the slide in wrong (easy to do)? Do you have the idle all the way down? 2 common problems after tinkering.

Guys - my bike (03 YZ450F) seemed to be running lean with a lot of popping and backfiring so I installed the JD Jet Kit. Blue needle 3rd clip, 170 main, and the stock 42 pilot. Now, I can't get the bike to start :) I went completely back to stock and it still won't start. I made sure the gas is fresh, new, plug, fuel line connected but can't get 'er going.

My first thought is that I possibly have dirt in the carb somewhere. In order to clean the carb, do I need to take it completely apart? I'm concerned with disconnecting the wires.... is that necessary? what do you suggest?

Also, if I hold in the hot start lever it will turn over for a second... does that mean it is too rich? Any suggestions?...

my 03 is same jetting w/ JD kit - :D - give it 3 blips of gas before kicking it over (primes the acc pump), try holding the hot start on while kicking it over - it will start and after it is warm it is fine....when mine is totally cold and the carb is completely drained of VPU4 (after each ride)- this is the drill to start it - I usually pull the choke on for 2-3 kicks w/ hot start pulled - then flip off the choke - pull hot start and it fires right up - in cooler temps I actually give it just a little gas with the hot start pulled - it starts after 3-5 kicks every time - and is fine after it is warm -

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