carburetor removal / jetting advice


3 replies to this topic
  • x2stroker

Posted May 25, 2005 - 06:47 AM

#1

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?...

  • r2millers

Posted May 25, 2005 - 03:49 PM

#2

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

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  • Fastest1

Posted May 25, 2005 - 09:16 PM

#3

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

  • Ga426owner

Posted May 26, 2005 - 01:25 PM

#4

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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