1981 GS 550 L air box to carb manifold

[Guest]

Why is there a 1/2 hose connection on the bottom side of this manifold? Where does it connect?

Thx

[Rich82GS750TZ]

#7 on the parts fiche at partsoutlaw.com
It connects to a nipple on the bottom of the manifold. It's a drain. if your engine has a loop for such drains on the back of the engine case, just in front of where the swingarm pivots, thread it through there. When I bought one for my bike a while back, the hose came with a cap and a clamp for the bottom end, even though it's not on the fiche. I think this the cap is a good idea, then anything that does drain through the hose, isn't spilling out on the road in front of the rear tire. But if you cap it, remember to un-cap and check it from time to time.

[Murphy67]

Hmm . Well that's what I thought but it would be a path of unfiltered air into the engine if not plugged.

Thanks for the explanation.

[Rich82GS750TZ]

Hmm . Well that's what I thought but it would be a path of unfiltered air into the engine if not plugged.

Thanks for the explanation.

Yes, a bit, maybe. I can't say whether my bike ran any differently with or without the plug, since I had the carbs cleaned and bench synced at the same time that I installed the hose with the plug. It's been plugged for years. I just removed the plug a few weeks ago and a few drops of some nasty liquid came out. But it was literally a few years.