as the tittle states how can i tell? the carbs have 138s in 1 and 4, and 140s in the 2 and 3, is that a good sign?

 

according to my manual that is not a stock jetting, mine should cover all the f3 models. Stock is 135 outside, 138 inside. How do you know what jets are in the carbs though, are yours numbered? If it has a non stock exhaust, or non stock air filter or something of that nature, then it's a good sign that it was jetted, otherwise it would be lean.

 

mine are numbered along the side. the needles are silver with mulitple settings but the clip is in the 3rd spot. i have another set of carbs on the bike now that came with it when i bought it. these are the ones that were on it when i got it. i took them off becuz it was running bad the carbs had sat up for a while and were full of junk so to get on the road fast i just threw the other set on. the bike has a full yoshi rs3 and will soon have a kn filter in it, if these carbs are jetted i planned on cleaning them and putting them back on

 

Yes, the main jets are numbered. I have seen 140 inners and 138 outers in what appears to be stock carburetors. In fact I have a set right now. The manual doesn't say anything about slightly bigger sizes, but I believe it's possible that they came with it. I just rebuilt a set that had these sizes in it and I did put 138's and 135's back in it just because that's what the manual says. I would think that if during production, if a bike was running a little leaner than they wanted, they would fit carbs with slightly richer settings. Usually when aftermarket jet kits are put in, the needles are replaced as well, like the ones that Battousi is seeing in his. The ones I have still have the original non-adjustable ones. The main jets look original, but you really can't be sure.

This is a "Factory Pro" jet that is in my wifes 97 F3. That's the reason for my other set of carbs. I'm putting an original headder back on with just a slip-on and I needed to put the carbs back to original.

 

thanx idodirt, so ur thinking that they are jetted? becuase of the adjustable needles?

 

Yes, I believe it's been jetted. Now, it's my understanding that when you install a jet kit that you not only replace the main jets, but replace the needles as well, and drill out the hole in the bottom of the slide. I've never put a jet kit in, so I don't know if you do different things to it depending on how large of a change you're making to the air-flow characteristics of the bike, like full exhaust, K&N filter, or modified airbox.

 

thanks alot man, keeps me from spending money. right now its just got a yoshi rs3 full exhaust, but im about to get a k&n for it so when i get the filter ill put the carbs with the jet kit back on

 

Do NOT put a K&N in there.Stick with paper.

Do not modify the airbox,unless you want your bike to never run right.

The middle cylinder jets are larger to keep the middle cylinders cooler.The inside cylinders get less air than the outside ones do.A wee-bit more fuel helps keep the temp balanced.

These bikes came in the country lean as a snake.They need to be fattened up a bit to run right.

Pull your plugs,that will tell you whether or not your jetting is close.The best way to tell is to put her on an EGR machine or a dyno with an EGR "snorkel".


Holla back.

 

Someone has definitely been inside his carbs. As you corrected me once, stock needles don't have e-clip settings.

If the needle is tapered, not going to straight point, then he prolly has a Dynojet Stage 1 kit in there. Those jet sizes sound like the ones I used for mine when I jetted my bike. K&N Filter and an unknown slip on exhaust

 

Thanks alot guys, looks like ill be cleaning some carbs here soon. i just didnt know if some carbs came with adjustable needles for altitude differences. Kuroshiro, then the jets that are in the carbs now will work with the mods that i have?