Air box boots? Should all be same size right?

[t3rmin]

Unfortunately had to yank my carbs and I noticed one of the boots on the air box had a smaller opening than the other three. They _are_ all supposed to be the same size aperture, right? Seems like somebody must have replaced that boot with the wrong one (perhaps from a smaller displacement bike?). Can't imagine proper carb balancing being possible with it set up like that.

[Jethro]

Yes, all the carbs bodies are identical (make sure they actually are- I've seen some pretty f'd up work from previous owners!)

[t3rmin]

Well it's not really the part that mates with the carb that's smaller. It is that rubber part, but the backside of it (where the other boots have a metal ring for stiffness) where the opening is smaller. So the carb throats are ok and the boot does fit the carb, but the opening as you look through the boots is obviously smaller overall.

What do you make of this michrofiche which seems to show a different part number for cyl 3's boot?:

http://www.mrcycles.com/fiche_section_detail.asp?category=Motorcycles&make=Suzuki&year=1981&fveh=2126

[t3rmin]

Freakin' weird.

Out of desperation I typed the part number I read off the odd #3 boot (13883-34500) into Google and came up with this:
http://70.85.253.252/spst/1982%20GS650E/01.htm (*EDIT* That site belongs to http://www.alpha-sports.com/ if anyone cares)

That site shows a microfiche of the air box with a different part number for the center-right and center-left boots (and a single part # for the outside boots). All the part numbers match up perfectly with what I've got.

This is odd indeed. Do you suppose that #3 carb is jetted differently too? The #3 boot has a substantially smaller opening -- it's easily noticable (even my non-mechanical wife picked up on it right away when I showed her the air box and asked if she saw anything odd about it). Why the heck would they do this from the factory???

[chef1366]

The smaller hole would speed up the air entering that carb. The reasoning behind it

[duaneage]

The longer boots go in the middle. I don't think they would fit on the outside anyway

[t3rmin]

The longer boots go in the middle. I don't think they would fit on the outside anyway

It's not a longer/shorter thing, it's one boot with a smaller inside aperture. The microfiche shows the part numbers for the outside boots as the same, and the two inside boots are two different part numbers. I've apparently got them arranged in the stock configuration, which has the smaller-opening boot on the #3 carb. It's weird.

[duaneage]

Maybe it hd something to do with the petcock vacuum being on #2?

Think about what happens when you try to put pods on. If they went to the trouble to tweak the sizes of the airbox boots, putting on pods can create a real tuning nightmare.