Jet size with aibox mod. and full system

[Bremms]

Hey Rexers...

I got a DJ kit for my bike. I'm going with a modded airbox for now I havea really slick Supertrapp
Full exhaust. 1200 03 BY THE WAY.. What mains should I use?? I know thw DJ supplied mains
90 or 94 are too small for a modded airbox. I was going to drill the 90's out to about a
102 or 104. I am removing the snorkel and venting cover. Maybe opening the side a bit more.
I have a full set of index/jet drills and can go from .0380 to .0600 in 5/10,000 increments.

I can always start at a102 and go up..

Thanks,
Marc

[Bremms]

Anybody have opinoins about the needle pos and idle screws?/ Should I use the DJ springs?
or will I get Too much gas at low revs when I whack it open..

[Jimbogsxr11]

Did you figure out what main size works best? I have an 01 1200 with the airbox mod/drilled, K&N filter, snorkel removed, stock pipe and a DJ kit installed. I don't know exactly what settings on the carbs yet as I just bought the bike but I need to change the main bacause the higher RPM pull is not there. I can pull the front with throttle in first though so low end is strong and clean. I plan to gut the stock pipe and see how that works but I want to get things sorted out with the current setup first.

[sillyhillbilly]

1.DJ jet sizes arent the same as keihn or factory pros. so when giveing an jet size be very sure you have the correct decimal size that that jet number goes to.

2. drilling your own jets unless you have good machinery isnt very trustworthy, versus the cost of new jets anyways, If you were doing N2O jets maybe drill your own, But the others well i hope your a realy good macninist with good machines to do this.
2. your still intthe quandry of what needle to use, most jet kits have special needles for tuning, the stock ones arent.

3.I am running an Ivans jet kit with Airbox mods, the 12 holes of 3.8 inch diameter and removal of snorkle.

4. I have best tuning with using mains equal too the Keihin jets of 110. the 112 that came with Ivans kit was a little rich, I went down one size and mileage went up.

there is an chart on the board that lists the jet number sizes versus the actual decimal size, do a search you will find it.
MBR