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IRISH-RACER-14
05-26-2009, 01:58 PM
i have a 06 300ex. it has a hmf slip on and a k&n air filter. im running the jet that came with the pipe. its the 128 or something like that. my exhaust is spluttering when i leave of trottle in a high speed. what jet should i get
Tommy Warren
05-29-2009, 10:55 AM
did you put a pilot jet in it? I would try that first. also check your plug to see what its telling you. maybe your too rich and need to go down a size or maybe you just need to adjust your air/fuel screw.
IRISH-RACER-14
05-29-2009, 02:40 PM
i would think she is running lean with all that backfireing. the plug is impostible to get out on a 300ex
ezdaar
05-29-2009, 02:52 PM
Originally posted by kdigginz
i would think she is running lean with all that backfireing. the plug is impostible to get out on a 300ex

Yup, I ended up useing a old plug and busting the top half of the porcelin off then used my dremal to grind back the fins on the head some. This allows a standard socket to get in there with out binding on the cooling fins.
Helps ATON! when doing a on the trail plug change.
tw62t
05-29-2009, 08:47 PM
Here is a good website for lots of information:
http://www.jetsrus.com/

Backfiring when letting off of the throttle means your pilot jet is probably too lean. You need to do a plug check. Take the quad out, run it as wide open as possible at the time, shut it off when under power then check the plug. Dont let it idle if you can help it. If the carb is running rich at all at idle, you will get false readings.

When I had to take the plug out of my 300, I used a swivel with the socket, worked great for me.

Read up on that website.
Tommy Warren
05-30-2009, 07:13 AM
I use one of those chainsaw plug removers with the screwdriver on the handle. fit in perfect.;)
Grimzella
05-31-2009, 08:57 AM
Originally posted by kdigginz
i would think she is running lean with all that backfireing. the plug is impostible to get out on a 300ex

really.. i thought it was easy.. heck the 400ex is harder to get out than the 300 is.. i couldnt even find a deepwell socket to clear the head,, to fit down over the plug on the 400ex... until i looked in the honda toolbag and found the plug tool.

300ex = easy
400ex = PITA