I have drag pipes and a screaming eagle (k&n)intake. i also put in a thunderslide jet kit with (i think) a 175 main and a 45 slo
I think i want a 180 or a 185 main, what do you think, and what do you have?

 

I too have drag pipes on a 2006 883. I installed the 45 slow jet but honestly it can stand to go to a 48. As for the fast jet the bike already had a 175 from the Motor Company and it was still too lean...Harley Shop was closed by the time I discovered this so I just ended up drilling it out to what amounts to a 195 and its running perfectly...hope this helps.

 

Do you have the extra stuff from the T-slide kit? T-slide kit destructions say to use 185 main if you have aftermarket airbox and/or exhaust. I'd start there. Shouldn't need more than that unless you change cams or do head work.

Also says to run with the stock 42 initially and go up if you need more then 3.5 turns on the mixture. I went up to a 45 on both my bikes. 48 is too much, even with drags.

Here's what I'm running...
Bike 1: 06 1200C Sport Bob
SE AC
CS Slip-ons
T-Slide kit
45/185 jets
3.5 turns on the mixture

Bike 2: 06 1200L
SE AC
Stock mufflers
DJ kit (3rd slot on the needle and all 3 shims)
45/180
3.5 turns on the mixture

 

I started with the 45 to be on the conservative side and find that the idle mixture adjustment screw is out quite a bit, which is why I think it could stand a 48. Im right at sea level around here and that 175 main was just too lean with the drag pipes. Im happy with the surgery I did on that main jet and its not fouling so...but then again every bike is different so starting out with recommended sets from the manufacturer of the jet-kit is a good place to start.

 

How much difference in HP or "seat of the pants feel" does a jet kit make from stock?

 

went by dyno instructions and for 1200c 170 main and stock slo jet 3 turns on mix but think it could run better

 

I'd recommend coming up one size on the slow jet for starters. Every bike is different and not sure how different your drags are to my mufflers but maybe try a 45/185 like I am running. I've got so much low end pull I had to reset the handlebars and over torque the riser bolts. I pulled the bars back trying to hold on when I opened up the throttle.

 

2005 883C near Phoenix, AZ (altitude approx. 1100')
Cycle Shack turnout slipons (about $180 from Heritage Cycle Works)
S&S air cleaner (about $170 from Sorgys)
45 pilot jet (about $5 bucks from the stealer, including tax :-)
175 main jet (stock)
drilled out plug and 2.75 turns out on the idle mixture screw
didn't drill the slide hole
didn't shim the needle
fart free and runs great!

Parts for Stage 1: around $355 total
Sound and Fury: priceless

 

ok i have V&H straightshots HS SE air cleaner the jet kit i got from HD the destructions said use 170 main and leave the slo jet alone , although i dont think it even came with a slo jet. runs pretty good but think it could have a little better response.