Dynojunk?!?!?!

[patches85]

Ok I'm running a high flow airbox(pictured)and a
megamax slipon. I live in central PA. I have the biggest jet dynojet gives you in a powerup kit (170). Middle slot on the needle and fuel screw 2.5 turns out. The problem is I am still getting a lean plug reading! Any help guys?

http://www.jetsrus.com/a_jet_kit_atv/honda_TRX400ex.htm

[underpowered]

with the mods you have you should be running rich with a jet that large. how are you reading you plug? are you letting it idle, varrying rpm's, or wide open runs? to get an accurate reading take it out and ride it, not just in the garage reving it. do some WOT runs through a field or if you live in a rural area up the road, getting up to the upper RPM range, then pull the plug as soon as you get back. do not let it idle too long of it will mess up the reading. you may just be too lean on your pilot jet. i have a 426, cam , pipe and K&N with no lid and am only running a 168 main on pump gas and a 178 on race fuel.

[patches85]

Remember these are dynojets their numbers are different.

[underpowered]

Originally posted by patches85
Remember these are dynojets their numbers are different.

yes, on the dynojets you are running than on a normal keihin jet. somewhere there is a chart showing the differences in the two. if i am thinking corectly i believe a dynojet is about 2 sizes larger than it says so a 170 kehin jet=165 dynojet.

[coryatver]

The chart is close but it is not right becuase dynojets don't match kehien jets they are in between sizes and flow different so you can not compare them. IMO Dynojets are junk i would throw them away and get some kehien.

[400exrider26]

is the jet kit speedyquad gave the link to kehien jets or jets that follow the same sizes as kehien or are they like dyno jets??? Would this kit be a good kit to buy for my 400ex because im getting a hmf slip on pipe and a filter... thanks

[patches85]

bump

the jets from the link i posted are to keihin specs

[Rico]

How does the bike run??? If it's not popping when letting off the gas on decel then it's fine. Fug the plug reading, it's not the 70's anymore.

My built 416 runs a 160 dyno jet and I've never ran a 170 in it with any setup, way to fat.

[patches85]

Yeah I changed the clip position and now its to rich. Think I'm gonna go back to the 165.

[400exrider26]

Me and my friend just took his carb off today... and it was easier than i thought it was gunna be exept those stupid screws suck to get off! We ALMOST striped them because they wouldnt come off! i got one question though... when ur putting the new main jet on the needle jet holder thing with the locknut does the jet wall (how there flat sides with angles so u can fit a socket around them) on the main jet have to match up with the sides of the needle jet holder that the main jet screws in to?? Also how tight are u really suppose to screw those screws in that hold the covers on the carb on? We just did them snug? I just want to make sure the carb wont leak or the screws wont fall out...

[patches85]

No I don't believe the sides need to line up. Tighten the screws up snug.