please save my lean running rat

[neonwitch]

hello, I've been following this forum for a while, gleaning what info I can and I must say it's been a better help than any manual or mechanic I have consulted.
I've been riding a 1980 gs1100et that I got for free from some guy that had it in his garage and didn't know what to do with it. It had about 9300m on the odometer and I have since brought it up to about 11,500. I changed the oil and filter about 1,500 miles ago.
Even though it looks ratty I really love this bike and want to keep riding it. here is the problem. Although the bike has always run strong, the stock airbox has never fit properly and slips off at the rubber boots that fit on the carb intakes. As a result, the bike runs lean. This hasn't been much of a problem riding it in upstate NY in the fall and early spring, especially since I am a fairly conservative rider. The engine never seemed to be overheated and always had plenty of power.
However, I recently moved to Brooklyn, NY. Anyone who is familiar with riding in the City knows that it is impossible to not abuse your bike. Between the summer heat and the stop-and-go traffic, and the fact that every stoplight becomes a death match between yourself and the thousands of battle-scarred cabs and delivery vans, many of whose drivers come from places where life is cheap, any mechanical problem comes to the forefront very quickly. on my last couple of trips to work, the bike has been running frighteningly hot. Yesterday, it started to bog down and puff a little smoke during a trip to Manhattan. I parked it and swore I wouldn't touch it again until I could address its mechanical problems. Bringing it to a mechanic in Brooklyn is out of the question due to my financial situation and the fact that most garages are pretty shady around here.

yes, I'm aware that I should have done something about the lean running condition long ago. It's just in my nature to put things off until they are staring me in the face.

So, my questions to the forum are as follows:

1. How can I tell if I have permanently damaged the bike, rendering further repairs pointless? It still starts, runs and drives fine until it heats up, then it gets hoarse off the throttle. I don't have a compression gauge at the moment or that would be the first thing I would do.

2. If the bike is fixable, is there a pod filter that is equivalent to the airflow of the stock airbox so I wouldn't have to rejet? I would have put pod filters on before but everyone has told me that GS s never run quite right with pods. Also, the procedure for the Dynajet stage three kit is a little intimidating; if I screw it up, another set of 34mm cvs will be hard to come by. Perhaps one of you knows a trick to get the stock airbox to stay on? It seems that they are a common problem among the gs series. The boots on the box just don't have enough length to them, and the plastic of the box has warped over time, so even if I get the outer boots on, the inner ones don't even reach.

Any advice that you guys have would be greatly appreciated. People call my bike a rat but you all know how great it truly is.

[spyug]

Welcome to the group.

I am no 1100 guru and indeed new to the GS myself but I can already tell these bikes are finicky when it comes to carbs and airboxes. My 750 won't run with the airbox off. I have never experienced that with any other bike or car. Weird in my mind.

If the bike has been running lean for a long time there is a likely hood you could be on your way to frying a piston or valve so you should try and check this out but repairing the fitting of the airbox or airfilters would be my first priority. A compression tester would not be too expensive from the likes of Harbourfreight so pick one up if you can. The compression test may not really tell you anything and for a more definitive analysis a "leakdown tester" would be necessary ( tests valves, head gasket rings etc.) but these are expensive and require some traiing to use properly. A good bike shop would be best ( if you can trust them).

I think I would steer away from after market pod filters at this point as these generally cause a bike to run leaner than stock necessitating a jet change to richen up. Changing jets is not hard however just fiddly and time consuming as you may need to change several sizes to find what works best for you.

If there are any bike wreckers around I'd try and source another airbox. If no wreckers how about E-bay or posting a wanted add on Craigslist. Have you looked through the buy sell on this forum?

If you can't source one then you are into pods but as mentioned you are likely going to have to rejet.

I'm sure some of the gurus here will give you some ideas so hang in but try and keep the trips short until this gets sorted.

Good luck.
Spyug.

[nabrams]

I'm from Brooklyn originally, so I feel like I can give it to you straight, and you'll be able to take it:
There are no shortcuts for you.
1. At the very least, you need to do a compression test - shell out the $40 for a guage and read the instructions.
2. Assuming all is well with compression - GET A STOCK AIRBOX, BOOTS AND FILTER and make certain there are NO air leaks - tons of posts (many from me) here about this.

You don't have time/energy to mess around with non-stock configuration with Brooklyn sapping every ounce of your energy.

[mortation]

Is the air box falling off the boots or are the boots falling off the carbs?

If its the carbs tighten the clamps if its the airbox pull it off and look inside. Each boot should have a metal C band inside that holds the boot on by the fact is expands outward applying pressure. You can get these off flatout for $.99 ea. I may infect have some good ones if you need them.

[chef1366]

More than likely all the boots for the airbox are hard as plastic. New ones are still available. Sometimes the intake hoses become cracked. These are available also. There is also a boot that connects the airbox to the filter box. You can still buy these also. For the filter lid I sealed it with truck camper seal. It is a foam type roll that has adhesive on one side. Don't take shortcuts and seal everything up. Also do a valve clearance adjustment. These bikes run a long time but not with a holed piston from a lean condition. Try here for parts. If the airbox itself is distorted I see them on Ebay all the time.