Jetting for dummies

Hey everyone, I'm new to the xs world (only 19 years of age) and am in love already. I've got stock exhausts but have pod filters, I've read up everywhere to change the jetting in the main jet, pilot, and air pilot jet. I have had no problem locating the three jets:
Main-in carb float bowl area.
Pilot-under rubber plug in float bowl area.
pilot air- in back bottom left hole.
I read that the main should be bumped up to roughly a 145, the pilot to a 45 and the pilot air backed up from a 130 to a 127.5.
Heres where the problem comes in, the pilot air jet I cannot find online to purchase for the life of me, is it called anything different? such as a small round type main jet? or anything of the sort? I've looked on xs650direct.ca and have found the proper large round type 145 main, and the 45 pilot, but not the pilot air.
If someone could help me out with some links or names I would greatly appreciate it!
thanks,
Nick Meisner

We need a little help.
What year bike?
Mods?
Bike hisrory?
What are you doing with it?
I'm assuming that you have BS34's because of the "air jet". Only they have a removable air jet though.
Take a look at www.amckayltd.com/carbguide.pdf
Read this 'til your eyes bleed!!!
The air jet is actually a small main jet. The threads are the same, but the "head" is a smaller diameter.

When you think you've figured out which jets you want, take your old ones (for a sample) into a local shop with a dyno machine. They will likely have a box of old jets, you can sort through and find the matching jets in the size you want. Pick up a few extras b/c you won't likely get it right the 1st time.

With pods as your only mod, you probably won't need to change all those jets. One size up on the mains might be all you need.

Hey Heres the bike specs as i know it:
1981 xs650, all jets are stock sizes (already read and made sure).
The bike ran great until i threw a set of pod fiters on it, which made it cut in and out and bog out. I'm sure they are the problem which is why when I order new jets, I will be ordering new pod filters. But yeah, the bike is 100% stock, even original pipes. Bought from a man that had it stored in his garage being neglected 65% of the time. the only thing I have done other than pods is turned the fuel mixture screw to three turns out. my main issue was finding a pilot air jet but now that I know the main jet is the large housing and the air jet is just a main jet with small housing, it will be much easier to find jets! I'm going to start with a 145 main 127.5 air pilot and a 45 pilot and go from there.
Any suggestions other than that? I have to order all of these jets witch is a pain in the Ass so I'd like to get it right the first time!
thanks!

I plan on doing bigger and better things to the bike such as pipes, which I know should be done before jetting or i'll have to go through the nightmare again, but hey, practice is what I need when I'm new to this

Do one change at a time. I have an '80 so we are using almost the same carb. I went to the Canadian needle and needle jet. Idle and rev great in the carport. Took it to the street and it fell flat on it headlight. Raised/lowered the needle. No good. Always idled and reved good in the carport but stumbled and spit below 3500. 45 pilot in. Checked the float levels too and found they were off.Transitioned better to midrange. Raised the needle to mid groove. MMMMm nice rideing now. Every time carbs were off, clean them. I ran Seafoam in the tank and its like a final cleaning. Yeah it coughed and spit the first 20 min of the first tank, but once it did its thing, that bike ran like it never had before! It was a different bike it ran so much better. Just like in the directions, an ounce a gallon. Its a good idea to slush out the tank after befor the next fillup to get the crud out of the tank after the first Seafoam treatment. Use a right angle inline fuel filter too. Not Mikes square filter. Mine nearly melted apart. The upper inlet was bent over so much. Thats enought for now. This worked for me. I'm just shareing.

Stop now. Make sure that the "pod filters" you have purchased do not have a lip that would block one of the 5 openings on the front of the carb. There is a known problem with some pod filters doing this and causing the bike to subsequently run poorly. Also, take the pod filters off and see how the bike runs.

5twins said:

With pods as your only mod, you probably won't need to change all those jets. One size up on the mains might be all you need.

Click to expand...

+1 on this info as well. This man knows what he is talking about.

The jetting info you were reading was written years ago and won't apply to your bike with only one mod. 145 mains will be way too big. I would get 135, 137.5 and 140 mains. One of those will probably be right with the pods and after you add pipes. For the pods only, I think just a main jet change will suffice. Once you add pipes, you may need the larger pilots. You may not ever need the air jet change. I've never needed to change them yet. I've always worked things out by just changing mains and pilots.

Alright thanks a lot for your guy's input! I'll stet with bugger mains and go from there! Really appreciate the comments

Just my two cents, but have you tried adjusting your fuel mixture ratio at all since the 3 turns out? I have an 81 and was running like crap, adjusted the fuel mixture and DIDN'T change any needle sizes and now it runs awesome, aside from timing!

Hey thanks everyone for the input. I took one pod off and it looks like the inside of it was blocking off the four holes in the carb. Since I live in nova scotia Canada where it never wants to stop raining I haven't had the chance to test the bike out without the filters. I will keep you all posted!