Change of carby needle

If I change my needle on my 2005 Wr250 from a #ERP to an #EQP how drastic would it lean the mixture out or should I rather change clip position first before this move.I was supplied an#EQP needle when I bought the bike new so I do not know for what conditions I am to use it ie: do I use it if I have fitted a non gen muffler and do all the mods the bike shop would do to race the bike.I have done all the mods and fitted a White brothers E2 slip on but feel the bike is running to rich.The carby as now is standard except for fuel pump bowl which has been replaced and a fuel screw fitted.Jetting is standard and I have gone up sizes on the mj and bike runs to rich.

Always start with small adjustments when jetting i.e. changing the clip position, and if those don't achieve the result desired then make more drastic changes.

Lean it out all the way with the clip before you slap a leaner needle in it.

Hi there guru,

I've been trialing jetting changes in my WR (06). As you have found , going up in main jet sizes gets to rich to quick - but it did improve the mid range. Dealer installed the ERM needle that came with the YRD kit (from new). I'm about to go down a clip position on the needle to see what that does. My bike des run a little ruff when coasting, but heh, how often does that happen. Interesting it sounds like a two stroke four stroking (the noise a two stroke makes when it's not burning all of the fuel real well). Most WRs seem to do this (well the ones I have seen)

I'ver never had the carb out, so it should be a xmas holiday challenge.

Thanks for your input guys.I will give it a whirl.I also have a JD jetting kit which i tried before but had no luck with I think I was trying to get rid of the bog with it which was the wrong thing I think.I might give that a try again.I ride at 306meters above sea level at temp of about 25 to 33 degrees any ideas on the JD needle and jet to use if i have a 162 mj in the carby now with standard needle.

ive got red needle on 3rd clip and a 170mj in... but I havent ridden in 2 months so I'll probably need to go to a 165 now its warmed up

i think pilot is 42 and leak jet is 60

i have heard of people running 155, so grab a few different jets and try it out. what works for some wont work for others

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