GS1100EX - Air Jet Size?

[Tourmaster]

Currently working on my buddies 1981 GS1100EX. Last summer his bike was running very lean with a 4 to 1 Vance & Hines "Street" exhaust system. The only other change to his bike at that point was a modification to the airbox to improve air flow. Following the V&H recommendations I swapped out his OEM 107.5 mains with 122.5's. Although V&H also recommended a one step, from 45 to 47.5 pilot jets, we started with just the main jet change. The bike ran much better with just the main jet change but still had a slight popping on deceleration.

Over the winter we purchased the 47.5 pilots, which I'm currently installing. We also decided to purchase carb kits (K&L's) in order to replace most of the other internals that are showing their age.

Here's my question ... I noticed that the installed Air Jets have 140 stamped on them. I assume, much like the other jets, that these are the OEM size, although I don't know this for sure? In the K&L kits I purchased, I noticed that there are two different sized Air Jets to choose from ... 160 or 170 ... but no 140's. Since the bike is running fine now, should I simply clean up and reinstall the 140's, or would there be some additional benefit to installing, say, the new 160's? Since these are "Air" jets ... will opening up this port size slightly have a "leaning" effect, or will the increase in this port size have another, and possibly beneficial effect? Just not sure why K&L would provide these slightly oversized Air Jets ... and thus looking for some advice and explanation.

Thanks

 

[Guest]

I used the 160s.

 

[chuckycheese]

160

160

I'm almost positive that the OEM size for your bike is 160. I have 3 sets for my bike and they all came with 160's in them. 2 of the 3 appeared to have never been disassembled. I tried to verify that on-line but never found anything that seemed to come from Suzuki. I suppose an "X" could be different than a US bike but, based on other models, it doesn't seem likely.

 

[Tourmaster]

Thanks guys. 160 it is.