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151 Posts
Discussion Starter · #1 ·
$7000 flame thrower.......
Just installed my HMF full system and unfortunately havent had a whole lot of time to test but boy I am getting a heck of a flame show !!

Originally before the pipe I had simply removed the baffle and changed the jets to the following

Elevation 760ft
Air box lid on.
MJ = 168
Pilot = 48
Needle yz = 3rd position
Air screw 1.5 turns out

Bike ran well throughout the range with just a touch of bog on the bottom.

Prior to installing the HMF

I left everything the same except I jetted up to a 175 Main.

The problem I am having is a blurb in the 1/4 to 1/2 range and upon inspection in the dark a 2 to 3 foot flame shooting out of the silencer when the engine is under load not on decelleration. Are these flames normal ? Never had anything similar with my FCR/Pipe combos on my 416EX.

I assume the flames are just left over fuel burning off which may indicate a rich condition but I am not sure where in the circuit to tinker.
My gut tells me to Raise the clip on the needle a notch however the bike seemed to run fine with the needle in its current setting with stock exhaust with the baffle removed. After reading a few posts I have always ran the bike with the idle turned up a few clicks could this be flooding the low end with too much fuel? I also considered change back to a 45 pilot but the bike just starts too damn easy and idles too smoothly with the 48. Last night it fired on the 1st try and it was in the low 30's a temp that would give my EX fits till warmed up.

Any input would be appreciated




264 Posts
I think the 48 is a little much. Works with the cam mod. I would use the 45 with the needle on the fourth the 175 should be ok. Pull your choke out first on the first stop then on the second. If it dies use the 45 for sure. Also if you have the airbox lid on and stock or restrictive intake you will never be able to use that jetting and still make power.
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