Workman, Venom said something about you may have a fix for the surge on a Muzzy exhaust.......would you mind sharing it with me :lol: ..........he didnt give me any details about it but here is my email addy if it is a map [email protected] Thanks dude
Let me look around and find the pics and I will post them here. I would have replied sooner but I've been out of town. Its basically a pilot jet installed inline to the air intake pressure valve. Cost about $3 and is very easy to do, takes about 5 minutes. It will smooth out the stutter quite a bit. I'll post the details tomorrow sometime along with the pics when I get a chance.
Hey, Workman, I did the mod a few weeks ago and it definitely improved the 2-3K operation - I had a question though: when a 12r has its stock pipe replaced doesn't the a/f sensor notice this and richen things to the extreme? If thats the case - when the jet is installed doesn't this return things to somewhat normal like the bike thinks it still has the stock pipe? Since I had my PC3 programmed with a DJ250 to lean it out significantly in the 2-3K range shouldn't it be richened now to compensate for the jet? Hope this makes sense
Yes it will help the Micron too if you are getting the "stutter".
Glad it helps. The ZX12 does not have an a/f sensor. It delivers fuel based on the fuel map and a combination of sensors. Although the controlling sensor varies depending on conditions, at 2-3000 RPMs the Air Intake Pressure sensor is the dominant sensor. It delivers fuel based on the vacuum signal it receives. When the bike is stock, the signal is smooth and the delivery is smooth as well. When you add a header, you reduce the backpressure and change the exhuast pulse. This in turn sends a somewhat erratic vacuum signal to the Air Intake Pressure sensor and in turn, you get a somewhat erratic fuel delivery. By adding the pilot jet, it helps to smooth out the vacuum signal by acting as a damping valve. Once the vacuum signal is smoothed out, the fuel delivery will be more consistent. Result is that it helps with the "stutter", it also helps a bit with the idle hunt but only after it warms up. It won't make it run as smooth as a stock bike but it will be worlds better than if you add a header without it.
To answer your question, yes, take it and get the air/fuel right. This mod won't richen or lean it out, it just makes the fuel delivery more consistent. Hope this helps.
I am having a hell of a time pulling the hose off the connector to insert my jet. What do you guys think of cutting the hose, throwing in 5 inches of new hose with the jet in it, then using a connector on each side to reconnect in-line. I know its unprofessional looking but it would be easy. Any performance loss, etc.?
I'm having a time finding 12.5 Mikuini Pilot Jet :evil: One dealer even asked me do i want a dirt bike or street bike jet? :?: .. Can someone direct me to some place online i can buy these thingys.. also what size hose and "T"...
as always gracias... :wink: