My buddy has a 300 ex with k&n filter and a dg pipe and canister. The dg pipe is almost a straightpipe if you ask me. He has all kinds of problems getting it dialed in. He is running with no airbox mods. Can someone maybe give me some jetting sizes he might want to try. I use to run a 130 in mine with the fmf megamax but he says it was to lean. I think he said he is using a 140 but I may be wrong. If he is I think he way overjetted it but he asked me to ask you guys.

 

Tell your friend that the only way to know what his engine needs is to run a test ride with a new plug, read the plug, and depending on the color, proceed from there.With pipes such as the DG and Cobra, whose chief attributes (?) are much higher decibles, he may not even need fatter jetting, or certainly not more than one size. Tell him to have the needle in the 3rd position to test.

 

hot shoe u will never know until u come ride my ex..yeah just keep puttin the cobra's a DG's down...i am a woods racer the dg makes the best power by far yes i have owned white brothers before 2...i have a uni filter removed choke complete dg alloy muffler 42 pilot 150 main...geared up 1 tooth will do 64mph...its jetted perfect with the 150 stock is a 122...thats the difference in power...adds alot of torque...i can ride a wheelin in all gears dont believe me come 2 TN an watch me

 

Sorry if I hurt your feelings..I bet if I asked you'd tell me you do this on a Breeze[img]i/expressions/face-icon-small-blush.gif[/img] .In any case, your reply is completely off topic from rob660's question, as is this one, so let's just drop it.

 

no actually its not..he asked about jettin u told me to keep it near stock...i say bump it on up.....cause i run a 150 he is runnin a 140 which depending on conditions could be right or 2 lean

 

well his plug is way to black to be running lean but maybe he should play with the pilot jet. If he is burning rich going up won't improve it. Should he try opening up the air box and see if it leans it out?

 

If the insulator and/or the electrode is black, it may be rich. I still recommend my original idea....a test ride with a brand new unused plug to get an uncontaminated plug reading. Then, based on that he may need to go to a leaner main jet. Remember. that the pilot jet only affects the idle to 1/4 part of the band.In rejetting, the accepted method is to jet for the main jet first before adjusting the other two.
If he is not sure how to do a proper test ride and/or plug read, He can email me for my tutorial & pic on the subject.

 

ok thx for the info

 

You didn't mention how it ran,the classic syptom of rich jetting is skipping on the top end,when you try to rev it out,it misses and surges. Lean,it will rev out,but will feel very weak on the top end,little power,and probably get very hot quickly. You did say the plug was black,probably a bit rich. Start at 2 sizes down from where you are now,warm it up,make a full speed run,if it still skips on the top,drop 1 size until it stops,then the top end should be good. As stated before,idle to 1/4 throttle is pilot jet,a good way to check that is get up to speed in 3rd gear,or roll down a hill,and let off the gas,let it coast to a stop,if it pops while coasting,turn the idle mix out 1/4 turn at a time until it stops popping,now bottom end should be ok. The midrange response you mainly set with the needle,if it seems crisp with no flat spots,you are fine,blubbers,too rich,raise the clip,bogs then surges,too lean,drop the clip. I know this is not the completely accurate way to set up,but it will get you real close,and you can always fine tune to your liking.

 

Well as far as how it is running it seems to do good on top end. But I tell you when I had my 300 ex it had a lot better throttle response. His seems real sluggish when you crack the throttle. Just seems like it is missing power somewhere. hell it didn't even want to wheelie in 3rd gear and mine use to do it in fourth. We will try some of your advice and see what we can figure out.