I know you can order just the jets from Factory Pro but most bike shops can get the size you need.

 

Rich means to much fuel not enough air. = smaller jets needed
Lean means to much air not enough fuel. = bigger jets needed

 

I got mine at the Honda dealership, had them in stock and they were about 5 bucks each. Not too expensive.

 

Ok, I bought the stock airbox and air intake and put that on. I also cleaned the carbs and threw them back on. So now my setup:
Stock airbox, k&n drop in filter, d&d slip on pipe. Main jets are 140 on the outside carbs, and 142 on the inside carbs.

It runs like **** now. I need to know what size jets to use, heres what happened.

1.) I bought the bike and it ran decent. I could not peg the throttle all the way without it spuddering lke it wasnt getting enough fuel or air. But it ran decent, just had to accelerate slowly.

2.) i took the tank off after about a month and saw the the previous owner had cut the top of the airbox off. The airfilter had duct tape over about 3/4 of it, exposing only 1/4 of the filter. I took the tape off and it got worse. I could not go over 75mph without it spuddering and wanting to die. I could not full throttle it in any gear, after about half throttle it would spudder and bog down.

3.) i cleaned the carbs and put the stock air box in. Now it is un-ridable. I can not get over 30mph. If i give it anyting past 1/8 throttle it spudders like crazy and bogs down to the point where i come to a stop and have to let off the throttle and ease up a little to move again.

I think the jets are too big? What do you think? What size jets do i need?

 

Shooting blind here. Guessing based on your bike the jets are too large. But best indicator will be the condition of your plugs. Give her a ride, come home and pull the plugs. Wet (which is my bet) from unburnt fuel and you're running way too rich.

From there you can try returning to stock jets. Or get a DJ kit so you can adjust as needed

 

I'd put the stock air filter back in it. My wifes F3 (the purple one) would run like crap with the K&N in it. No power at all.

 

all good ideas, but try workin with ur air soldenoid....that is the piece that has three hoses comin off of it....each hose is utilized at different speeds...if one is clogged,blocked , or hooked up incorrectly you could have problems such as you are describing..if u need a link to a downloadable manual for your bike i can help.....i hope this helps as i know where ur frustration comes from...i just acquired a 98 f3 in boxes....i was missing half of the bike and am now only a few parts away from completion....good luck and be careful

 

Anyone else here run a K&N and have good or bad luck with it?

Where is the air solenoid located?

 

I'm in a similar situation. Bike has full Vance&Hines exhaust, took her in for a tune up and had them put a K&N filter on and it ran like crap afterwords. at higher speeds with a good head wind it bogs way down at about 7k rpms to where there is ZERO acceleration. So I've either got to take my carbs apart to see what the jetting is or break down and put a stock air filter back in and see what happens.

 

There could be several things. As Kuroshio said, you're going to need a baseline. Set up the carb with stock jetting and also check the needle size. Once together, you should also sync the carbs. As suggested before, test you're air solenoid valve just behind the box. Also make sure all the hoses are clear of any blockage and connected correctly. One more thing, check the diaphragms/vacuum piston for holes. If there is the smallest hole, it would cause similar problems due to lack of vacuum.