Airbox to cones...


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I'm thinking about picking up a couple of the xs performance pods from mikesxs and I was curious about what kind of tuning I need to do to the carbs. Is this something I can do on my own or do I need to have them done professionally? Thanks!!!
Josh, are you going to put these on the 650 or the 400?

Either way, if you decide to run pod filters, you'll probably have to do some rejetting. It will also depend on how free flowing your exhaust is. You'll probably have to go up a size on the pilot jets and up a size or two on the main jets along with playing with the needle height if it's adjustable. If you have a more free flowing exhaust along with the pod filters, you might need to go even higher. If your needles aren't adjustable, you can put spacers under the clip to raise the needle, but you can't lower it.

If you can do it yourself or not depends on how mechanically inclined you are and how much you are willing to play around with getting the jetting just right. It can be a very time consuming process. You'll probably have to have the carbs on and off the bike at least to few times to get it running just right. You could do a series of plug chops to help you make sure you aren't too lean or rich. If you like working on your bike, go for it. If you mostly just want it to run well and just want to ride it, I'd stick with the stock airbox and filters.
Ahhh ok. I thought it might be a tedious process. I guess after what you said I'm just going to stick with the stock airbox. Being in school is enough of a headache for me, I don't need anymore outside of the classroom! Thanks for the advice!
I'm getting ready to put the pod filters on by bike this evening. Am I going to find carb adjustment and jetting in my manual? I'd much rather put the effort in to making the necessary adjustments to make them work rather than dealing with the factory airboxes. I just want to make sure I'm gonna get them right without too much hassle. I'll be running the stock mufflers for a while, then I might switch to the Taper Tip Mufflers on mikesxs.
Unfortunately there is no reciepe for jetting these carbs when making changes to filters or exhaust. You can only start with an educated guess and work your way thro it, until you reach the right set up for your bike.
You prob going to have to go up one size on the pilot & one or two on the mains tho, maybe drop the needle one as well
Read the carb manual from the garage, print it out and keep refering to it and you will get it running sweet :thumbsup:

Thanks a lot Kev, I hope it this doesn't take too long though, I'm getting impatient with getting this bike on the road. Glad I found the forum, lots of help from nice people.
LosD & Josh, I have done what you guy's are proposing to do. It makes the carbs allot easier to work on for sure. What I ended up doing, after I tried to re-tune them myself, was to get a set of XS John's needle's. I had gotten bigger pilot & main jet's, And the Canadian needle kit's, only to find a big flat spot in the upper rpm range, & fuel economy went way down. After installing John's set-up, my bitch runs a whole lot better, & fuel mileage is about 50 mpg. My bike is an'80 G model with the BS 34 carbs. Engine is stock, with the XS pod's & Mike's 2-1 header with the taper tip muffler. John's kit is a little pricey, but I feel worth every penny, because they work, & he'll help you with ANY problem's. Even now, with the understanding I've got on these carbs now, I was still having problem's before I did is Needle swap & jet recommendation's. The BS34's are notoriously lean, but it doesn't take allot to get too rich, and possibly cause cylinder wash.
INxs has a good chart posted, esp. on the range of the jet's, and when they kick in and work untill the next kick's in. If you'll notice the pilot work's through the whole rpm range.
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Thanks a lot Kev, I hope it this doesn't take too long though, I'm getting impatient with getting this bike on the road. Glad I found the forum, lots of help from nice people.

Plenty of people on here always happy to help Los D :)
Your bike should start up and run with the jets you have, it just wont be quite right :(
If it tends to pop thro the exhaust when you shut off the throttle, go up one on the pilot jet, you need to remove the float bowl for this.
if it dont pull hard from about 5000RPM go up on the mains, if your carbs are 38's like mine with a drain plug in the bottom of the float bowl, you can change the mains thro the drain plug. Makes it quite simple tho maybe best to remove float bowl first time to see what you are doing and to find a screwdriver bitt hat fits really well. Even grind a bigger one down for a really good fit.
Its all explained really well in the carb guide
Yes I agree with all of the above and in my experience with staying with the stock carbs (no problems) I removed the main jets and had a carby guy (any carby reco place will do it) drill them out by 10 more so what I had in the end were mains at 140 instead of 130.
This worked very well with K+N filters and straight thru pipes,Harley style tapered turbos and full length headers.The only problem I found by removing the ugly stock air box was securing the carbs to the manifolds so I made up a couple of brackets that secured them with no problems.I think that the stock airboxes (according to a Yamaha engineer) were designed so that the diaphragms would raise the needles on decelerating therefore still supplying sufficient fuel to the engine without running too lean.
Yep no worries Travis,thankx for the greetings.
I discovered an easy way of removing the carb bowls without having to remove the carbs,but even though it worked 4 me it may not work for everyone.It all depends on how good condition the philips head screws are in and what I did was took a small socket set rachet and inserted the adapter to it with a philips bit attached and holding pressure on it and unscrewing,but it's like I said,it may NOT work for everyone.Another thing that can be done is to convert the bowl screws to socket and instead of attaching the PH use the 4mm socket bit.Sometimes it's good to refit new screws if that is the choice to make.
As INXS says...."regret is forever" what you gotta do Los D but; if you do remove those stock airboxes & brackets....don't throw them away and don't be one who never heard that they also serve as the rear mounts & support for the carbs and also stabilize the battery tray! And don't have a carb fall off while on a canyon ride in the middle of nowhere and then have to buy a replacement set of boxes off ebay with brackets from royfisk just because you thought the boxes were too rusty & ugly to remain while you got your bike running right.

And....please don't ask me how I know all these things!

FWIMBW.... get real familiar with your XS... it's carbs, points & timing before you start changing air cleaners, exhaust or ignition systems.

Best, Blue
Nothing is getting thrown away, I wouldn't think of it when dealing with an old bike. I know if or when I ever sell this one that the next guy might appreciate having as much of the original parts as I did when looking for this bike. That and I always want the option of going back to the way something was designed to be. Thanks for some solid advice.
XSjohn modified his air boxes by making another inlet hole between the 2 existing ones and inserting a rubber hose and removed part of the support inside that restricted the air flow. This gave a lot more air to the carbs and if i remember properly he had to up one on the main jet ............Can't find the info that i thought i had so this is from my memory.
The stock air boxes were one of the crap items chucked in the bin along with the swing arm bushes and head stem bearings.I made sure that my carbs would not pop off while riding around by securing them properly and I also believe that an engine needs to breathe to allow for maximum performance,something Yamaha didn't consider when they produced these dam fine motorcycles.
These are some great responses and links...well worth sigining on here just for that info.
I'm about to fire mine up after going to pods and flow thru cocktails shakers type exhausts. Now I know right where to start and should help me tune it right on shortly.